_Copulation._
The reproduction of the species is effected by means of an act of
copulation on the part of a male and a female individual, both of whom
must have attained complete sexual development. In all the sequence of
reproductive processes it is copulation alone that is a voluntary act,
all the other processes being independent of the will and even of
consciousness.
A characteristic difference between man and the lower animals lies in
the fact that in the human species sexual pleasure and the act of
copulation may occur at any season of the year; and a further
characteristic difference may perhaps be found in the fact that in the
great majority of individuals of the human species the psychical process
of “love” plays a determinative part. _Voltaire_ pointed out that to man
alone among animals are known the embrace and the joy of the kiss.
The significance of the kiss is depicted by _Grillparzer_ in the
following verses:
Auf die Hände küsst die Achtung,
Auf die Wangen Wohlgefallen,
Seelige Liebe auf den Mund.
Auf den Nacken das Verlangen;
Uberall sonsthin Raserei.[45]
In this act of conjugation between two individuals of the same species,
differentiated each from the other by the characteristics of sex, the
active, provocative rôle is allotted to the male, the passive, receptive
rôle, to the female. The modest and coy reluctance characteristic alike
of the maiden and of the wife, promote an increase of sexual excitement
in the opposite sex, and this not only in a man of purely sensual
character, whose vanity is stimulated by his being the chosen one among
many—a circumstance which, in view of the great dependence of the sexual
act upon psychical processes and imaginative influences, is by no means
devoid of importance. The woman’s coy reluctance must be overcome by
means of a tender strategy before she is willing to grant the final
possession of her body; and the act of copulation forms at the same time
the conclusion of the physical and mental yearnings of the lover, and
the commencement of the new-coming being. There is thus a physiological
reason for the advice given by the celebrated surgeon, _Ambroise Paré_,
that a man, before completing coitus, should employ some of the delicate
and sensually stimulating manipulations of the earlier stages of
courtship, for, he writes, “aucunes femmes ne sont pas si promptes à ce
jeu que les hommes.”
The potency for intercourse of the sexually mature man, his capacity for
the introduction of the erect penis during the act of copulation, is
dependent on the fact that sexual excitement gives rise to a sufficient
stimulus which, acting on the erection centre (and presuming that the
centre and its afferent and efferent tracts are normal), leads to an
increased flow of arterial blood to the penis and a diminished outflow
through the veins of that organ, and consequently to its erection. The
cerebrum is the organ in which the sensation of libido sexualis, of
sexual excitement, has its seat; with this higher centre is connected by
means of intercentral nerve tracts a lower, mechanical, reflex centre,
situated in the lumbar enlargement of the spinal cord, and presiding
over the performance of the act of copulation; it is moreover probable
that nerve fibres proceed from the spinal cord direct to the blood
vessels of the erectile tissue, by means of which the calibre of these
vessels can be lessened or their extensibility diminished. The relation
of the erector nerves (nervi erigentes) to the penis is by many
physiologists compared to the relation of the vagus nerve to the heart.
In the quiescent state the small arteries of the penis and perhaps also
the cavernous spaces of that organ are in a state of mean contraction,
so that they offer a considerable resistance to the passage of the blood
current. When now the nervi erigentes are excited to activity, the
hitherto tonically contracted vessels of the penis undergo, according to
the school of physiologists just mentioned, relaxation, so that they
dilate under the pressure of the blood within their walls, and, the
previous resistance to the flow being now removed, the blood pours
freely into the cavernous spaces of the penis, and distends these to the
uttermost. In this manner erection is effected, rendering possible the
insertion of the penis into the genital passage of the female; with the
culmination of the sexual act, the semen is ejaculated, the muscles of
the prostate and the membranous portion of the urethra together with the
ischiocavernosus and bulbocavernosus muscles, all acting strongly and
simultaneously.
By the contraction of the muscular apparatus just described, the penis
is constricted in the neighborhood of the pubic symphysis, and this
further hinders the outflow of the blood from the corpora cavernosa,
increasing the intensity of the state of erection of the penis. Should
the relaxation of the corpora cavernosa, dependent upon the stimulation
of the nervi erigentes, be incomplete, it is not possible for sufficient
blood to pass into the cavernous spaces to exercise considerable
pressure upon the efferent veins, and thus complete erection fails to
occur. If, again, the contraction of the muscular apparatus at the root
of the penis is insufficiently vigorous, complete erection likewise
fails to occur; the organ becomes semi-erect only, or erect for a period
too short to permit of the completion of intercourse.
Since, physiologically speaking, conception is the purpose with which
copulation is effected, the ejaculation of the semen must be regarded as
the principal object of that act; now in normal conditions, ejaculation
takes place only when the penis is fully erect. Associated with the
erection of the corpora cavernosa is a swelling of the caput
gallinaginis, whereby the orifices of the ejaculatory ducts are directed
forwards toward the membranous portion of the urethra, and at the same
time the backward passage to the bladder is cut off. By this mechanism,
the urethra, which usually serves as the canal for the outflow of urine,
is made for the time being solely subservient to the purposes of the
sexual act. That the outlet from the bladder is obstructed by the
swollen caput gallinaginis when the penis is erect, is shown by the
familiar fact that a man whose penis is erect cannot pass water,
although the way is freely open for the ejaculation of the semen.
Before ejaculation begins, the urethral glands already begin to secrete;
and when erection is powerful and prolonged, this secretion often makes
its appearance at the urethral orifice in the form of drops of a clear
somewhat tenacious fluid. _Ultzmann_ considers that the function of this
secretion is probably to moisten the walls of the urethra, over which
the acid urinary secretion is continually flowing, with a protective
alkaline fluid, and thus to prepare the canal for the passage of the
semen. An analogy may be found in the secretion of the cervical glands
of the uterus in the female, for this secretion has been found to
enhance the activity of the movements of the spermatozoa. If now during
copulation the moment of ejaculation begins, the male experiences at the
same time a sense of voluptuous pleasure and a feeling of muscular spasm
in the perineal region, and this indicates the commencing evacuation of
the contents of the seminal vesicles through the ejaculatory ducts.
Simultaneously, the secretion of the prostate is poured into the
urethra. The semen now gradually passes out through the narrow
ejaculatory ducts, and, since in consequence of the swelling of the
caput gallinaginis, it cannot pass backwards towards the bladder, it
runs forwards, and accumulates in the bulb of the urethra, the
physiological excavation of that tube. As soon as a considerable
quantity of the semen has collected in this situation, so that the bulb
of the urethra becomes distended, reflex contractions of the
bulbocavernosus muscles ensue, by means of which the seminal fluid is
forced out of the urethral orifice. In cases in which this muscular
apparatus does not function properly, as in the paralytic form of
impotence, the semen during ejaculation is not ejected in a forcible
jet, but rather flows slowly, as from a lax tube partially filled with
fluid, from the urethral orifice.
We are indebted to _Roubaud_ for a classical description of the
phenomena of copulation, and this description is here appended. It runs
as follows: “As soon as the penis enters the vaginal vestibule, it first
of all pushes against the glans clitoridis, which yields and bends
before it. After this preliminary stimulation of the two chief centres
of sexual sensibility, the glans penis glides over the inner surfaces of
the two vaginal bulbs; the collum and the body of the penis are then
grasped between the projecting surfaces of the vaginal bulbs, but the
glans penis itself, which has passed further onward, is now in contact
with the fine and delicate surface of the vaginal mucous membrane, which
membrane itself, owing to the presence of erectile tissue between its
layers, is now in an elastic, resilient condition. This elasticity,
which enables the vagina to adapt itself to the size of the penis,
increases at once the turgescence and the sensibility of the clitoris,
inasmuch as the blood that is driven out of the vessels of the vaginal
wall passes thence to those of the vaginal bulbs and the clitoris. On
the other hand, the turgescence and the sensitiveness of the glans penis
itself are heightened by compression of that organ, in consequence of
the ever increasing fulness of the vessels of the vaginal mucous
membrane and the two vaginal bulbs.
“At the same time the clitoris is pressed downward by the anterior
portion of the compressor muscle, so that it is brought into contact
with the dorsal surface of the glans and of the body of the penis; in
this way a reciprocal friction between these two organs takes place,
repeated at each copulatory movement made by the two parties to the
action, until at length the voluptuous sensation rises to its highest
intensity and culminates in the sexual orgasm, marked in the male by the
ejaculation of the seminal fluid, and in the female by the aspiration of
that fluid into the gaping external orifice of the cervical canal; so
true, indeed, is this, that it is a difficult matter to give a picture
at once accurate and complete of the phenomena attending the normal act
of copulation. Whilst in one individual the sense of sexual pleasure
amounts to no more than a barely perceptible titillation, in another
that sense reaches the acme of both mental and physical exaltation.
“Between these two extremes we meet with innumerable states of
transition. In cases of intense exaltation, various pathological
symptoms make themselves manifest, such as quickening of the general
circulation, and violent pulsation of the arteries; the venous blood,
being retained in the larger vessels by general muscular contractions,
leads to an increased warmth of the body; and further, this venous
stagnation, which is still more marked in the brain in consequence of
the contraction of the cervical muscles and the backward flexion of the
neck, may cause cerebral congestion, during which the consciousness and
all mental manifestations are momentarily in abeyance. The eyes,
reddened by injection of the conjunctiva, become fixed, and the
expression becomes vacant; lids close conclusively, to exclude the
light. In some, the breathing becomes panting and labouring; but in
others, it is temporarily suspended, in consequence of laryngeal spasm,
and the air, after being pent up for a time in the lungs, is finally
forcibly expelled, and they utter incoherent and incomprehensible
words.”
The impulses proceeding from the congested nerve-centres are confused.
There is an indescribable disorder both of motion and of sensation, the
extremities are affected with convulsive twitchings, and may be either
moved in various directions or extended straight and stiff; the jaws are
pressed together so that the teeth grind against each other; and certain
individuals are affected by erotic delirium to such as an extent that
they will seize the unguarded shoulder, for instance, of their partner
in the sexual act, and bite it till the blood flows.
A period of exhaustion follows, which is the more intense in proportion
to the intensity of the preceding excitement. The sudden fatigue, the
general sense of weakness, and the inclination to sleep, which
habitually affect the male after the act of intercourse, are in part to
be ascribed to the loss of semen; for in the female, however energetic
the part she may have played in the sexual act, a mere transient fatigue
is observed, much less in degree than that which affects the male, and
permitting far sooner of a repetition of the act. “_Triste est omne
animal post coitum, praeter mulierem gallumque_,” wrote _Galen_, and the
axiom is essentially true, at any rate so far as the human species is
concerned.
The question has been mooted, and many earnest inquirers have devoted
much thought thereto, whether in this moment of most intense sexual
gratification it is the male or the female that experiences the greatest
amount of pleasure. As in the case of all questions the data for the
solution of which are at once very various and very variable, so in this
case also, very different opinions have been put forward. “In fact,”
writes _Roubaud_, “when we take into consideration all the circumstances
by which the intensity of sexual sensation is influenced, it may well be
doubted if it is at all possible to find an a priori solution for the
problem. When we take into consideration the influence exercised by
temperament, constitution, and a large number of conditions both general
and special, on sexual sensibility, we cannot fail to be convinced that
this problem, in consequence of all the complicated characteristics it
presents, is actually insoluble.”
In regard to the pleasure experienced in the act of intercourse, a
remarkable distinction is drawn by _Gutceit_. The male, in every case
and with every woman, experiences the full degree of pleasure; and even
though from the mental point of view this pleasure may be enhanced by
inclination, attraction, and mutual love, from the physical point of
view there is no difference between different acts of intercourse, so
that the cynical old Roman was right when he wrote. “_Sublata lucerna
nullum discrimen inter foeminas._” But in the case of the female it is
very different. Her first experience of sexual relations is a very
painful one, and this pain prevents all enjoyment as long as it
continues, as it does in many women for one, two, or even four weeks.
And when this period is once over, not more than two women in every ten
experience the pleasure of sexual intercourse in its full intensity. Of
the remaining eight, four have indeed an agreeable sensation during the
rubbing movements of the sexual act, but it is a long time before they
experience a sensation analogous in its intensity to that which in man
accompanies the act of ejaculation. In some women it may be six months
after marriage before the true sexual orgasm is experienced, in others
it may be a year, or even several years; in a considerable number this
does not happen until after they have given birth to several children.
As a result of numerous observations on this point, _Gutceit_ asserts
that in women sexual pleasure is experienced only in intercourse with a
man who is beloved, or against whom, at least, no repulsion is felt; and
that no pleasure is felt by a woman in intercourse with a man towards
whom she feels an actual dislike. Further, he maintains, that a woman,
loving another man, and feeling pleasure in intercourse with him, has on
the other hand no voluptuous sensations during intercourse with her
husband, whose embraces she permits only from a sense of duty. Thus in
the male, intercourse is always pleasurable, while in the female,
pleasure is experienced only when certain conditions are fulfilled.
Contact with the male genital organs stimulates in the female the
sensory nerves of the vulva, the vestibule, and the vagina; the nervous
stimulus is transmitted to the cerebral cortex, where it gives rise to
the sensation of sexual pleasure, and causes, through the intermediation
of the genito-spinal centre, a number of reflex actions. As sensory
nerve terminals of such reflex arcs, the final ramifications of the
pudic branch of the sciatic plexus play the most important part; in the
clitoris these nerves are beset with a peculiar kind of end-bulbs, the
genital corpuscles discovered by _W. Krause_; from their structure these
corpuscles seem admirably adapted to respond to the very slightest
stimulation, producing voluptuous sensations and perceptions, and giving
rise to various reflex manifestations. The first part of the path of the
afferent impulses by which sexual pleasure is aroused is constituted by
the dorsal nerves of the clitoris. The reflex changes consequent upon
sexual excitement begin already in the vestibule, inasmuch as the
secretion of Bartholin’s glands, which are compressed by the action of
the constrictor cunni muscle, is expelled during coitus, the secretion,
owing to the situation of the orifices of Bartholin’s ducts, passing
over the external genitals. The clitoris becomes erect; the blood in the
bulbs of the vestibule, the venous plexus situated around the margin of
the vestibule along the boundary between the labia majora and the labia
minora, is pressed into the glans clitoridis, the erection and
sensibility of this structure being proportionately heightened. By the
action of the constrictor cunni and ischiocavernosus muscles, the
clitoris, the distal extremity of which is bent downwards at a right
angle, is drawn down and pressed against the penis.
At the entrance of the vagina is the sphincter vaginæ muscle, whose
action is reinforced by muscular fibres running in the middle coat of
the vagina itself. It is probable that the muscular activity of the
vagina and the uterus facilitates the entrance of the semen into the
cavity of the uterus.
Dorsal decubitus is rightly regarded as the most correct position,
physiologically speaking, for the woman to assume during coitus. That
from the earliest times and in the most diverse races, this position has
been customary, is shown by numerous antique paintings and statues, and
by the reports of those who have studied the customs of savage races.
Various other positions are, however, occasionally assumed; thus,
_Ploss_ and _Bartels_ report, that among the Soudanese, coitus is
practiced in the erect posture, with the man standing behind the woman;
that among the Inuits (Eskimo), the act is performed in the manner usual
among quadrupeds; that among the Swahelis in Zanzibar, and among the
indigens of Kamschatka, the lateral posture is customary; and that among
the Australian blacks, coitus is usually effected in the crouching
posture, both parties squatting on their hams. The same writers remind
us, that in the old calendars of the fifteenth, sixteenth, seventeenth,
and eighteenth centuries, definite commands and prohibitions for the
conduct of marital intercourse are to be found, and that lucky and
unlucky days, respectively, are specified for the performance of the
act. These recommendations would appear to be relics of antiquity, for
in the Sanscrit work _Kokkogam_, under the heading “_Sexual Intercourse
According to the Days of the Month_,” exact instructions are given for
the proper performance of coitus.
In the _Kamasutra_ (the Indian _ars amatoria_, a work only in recent
days rendered accessible to European readers in the translation of _R.
Schmidt_), several chapters are devoted to the detailed description of
the various methods of copulation, and rules are given for the carnal
union of man and wife. But, as the Indian author justly remarks, “Rules
are of value only for the control of moderate desire; when the wheel of
passion has once begun to roll, to prescribe a course is no longer of
any avail.” In this work, sixty-four varieties of erotic enjoyment are
enumerated, and we find an _explicatio coitus secundum mensuram, tempus,
naturam, de modis inter coitum procumbendi, de minis coitibus, de coitu
inverso, de viri inter coitum consuetudinibus_.
At times, in order that coitus may be effective, some other position
than the natural one is indispensable. Such a necessity has been
recognized even by theologians, by whom any divergence from nature in
this matter has usually been regarded as sinful. For instance, in the
work of _Craisson_, _De Rebus Venereis ad Usum Confessariorum_, we read:
“_Situs naturalis est ut mulier sit succuba et vir incubus, hic enim
modus aptior est effusionis seminis virilis et receptioni in vas
femineum ad prolem procreandum. Unde si coitus aliter fiat, nempe
sedendo, stando, de latere, vel praepostere (more pecudum), vel si vir
sit succubus et mulier incuba, innaturalis est.... Sed tamen minime
peccant conjuges si ex justa causa situm mutent, nempe ob aegritudinem,
vel viri pinquetudinem, vel ob periculum abortus; quandoque ait St.
Thomas, sine peccato esse potest quando dispositio corporis alium modum
non patitur._”
In certain pathological states, as for the prevention of sterility, an
abnormal posture during coitus may advantageously be recommended, in
order to favour the entrance of the semen into the cervical canal, and
to allow the semen to stay longer in the vagina before it flows out. An
old and often efficacious means for this purpose is the performance of
coitus with the woman in the knee-elbow posture. In order to favour the
entrance of the semen into the deeper portion of the genital tract,
_Hegar_ and _Kaltenbach_ recommend that after coitus the woman should
remain for some time in the knee-elbow posture, while the man from time
to time gently presses up the anterior abdominal wall, and then abruptly
relaxes the pressure.—In the _Talmud_, coitus was regarded as unfruitful
if performed when the woman was in the erect posture.
_Casper_ reports the case of a woman with severe scoliosis, who had long
remained sterile, and who only conceived (and was subsequently happily
delivered) after performing coitus in the abdominal decubitus.
_Guéneau de Mussy_ suggests the following, very characteristic, method
of ensuring fertilization, one which also certainly dates from great
antiquity: “_Sed haud illicitum mihi visum est, si post diversa
tentamina diutius uxor infecunda manserit, ipsum maritum digitum post
coitum in vaginam immittere, et ita receptum semen uteri osteo admovere.
Et cum ostiolo uteri haeret, ut in pervium canalem spermatozoidum
motibus faventibus, prodeat, sperare non absurdum._” _Eustache_ reports
a case, the wife of a physician, in which this manoeuvre was effective
in ensuring conception.
A similar procedure has been employed with success by Kehrer, in a case
of enfeebled potency on the part of the male, leading to premature
ejaculation. A speculum was introduced into the vagina, and through this
instrument the semen, ejaculated in consequence of sexual excitement,
was introduced into the vaginal fornix; conception ensued. In an
analogous manner, _A. Peyer_ recommended, in a case of partial
impotence, in which special manipulations were needed to bring about
ejaculation, that conception should be favoured in the following manner:
Erection having been effected by ordinary sexual contact, the
manipulations needed to produce ejaculation were carried out, and the
penis was intromitted into the vagina the moment before ejaculation
occurred. This has been done with fruitful results. _Englisch_ reports
the case of a hypospadiac who, in order to render coitus effective, used
a condom in the anterior extremity of which he made an aperture. In this
way he became the father of three children.
In very obese men with extremely protuberant abdomens, we may recommend
for the furtherance of conception that they should have intercourse with
their wives _a parte posteriori_; and the same recommendation may be
made in cases in which the wife herself is extremely obese. In
Australia, it is said that among the indigens, coitus is usually
practiced _a posteriori_; and there is a saying in the Talmud to the
effect that sexual intercourse performed in the ordinary manner does not
lead to the conception of infants so good, wise, talented, and promising
as those whose conception is the result of coitus _a posteriori_.
Mohammed, on the other hand, declares, “Your wives are your tillage, go
therefore unto it in whatsoever manner ye will.”
In cases of retroflexion of the uterus, with a markedly forward
direction of the vaginal portion of the cervix, I have recommended to
the husband that he should perform coitus with his wife in the upright
sitting posture. In this posture the fundus uteri passes downwards and
forwards, whilst the vaginal portion of the cervix passes upwards and
backwards.
In cases of retroversion of the uterus with the formation of a
cul-de-sac in the posterior vaginal fornix, _Pajot_ recommends, with the
aim of temporarily restoring the uterus to a position in which the
occurrence of conception is favored, that for three or four days prior
to coitus the patient should retain the fæces, eating the while freely
of eggs and rice, and taking a small opium pill every evening; in cases
of anteversion, the patient should retain her urine for a considerable
time—five or six hours—before coitus; and in cases of lateral version he
recommends that the patient should have intercourse while lying on that
side towards which the vaginal portion of the cervix is directed.
_Edis_ recommends that in cases in which there is sterility dependent
upon backward displacements of the uterus, that the organ should be
replaced while the patient is in the genu-pectoral posture, and a
pessary inserted; coitus should then be effected without the patient’s
changing her posture.
In the human species as compared with the lower animals, there has been
a notable diminution in the frequency of the separate acts of
intercourse, a diminution dependent upon the higher vital aims of the
former. _Burdach_ formulates as a physiological law that the frequency
of sexual intercourse is inversely related to the duration of the act.
Amongst all civilized races, sexual intercourse ceases during
menstruation, since in the normal man there is aversion to intercourse
with a menstruating female.
By the Mosaic law, intercourse with a woman during menstruation and for
seven days after the cessation of the flow, was forbidden under pain of
death. The _Talmud_ further ordains that a purifying bath shall be taken
by the woman a week after menstruation. By intercourse itself, moreover,
both man and woman were rendered unclean to the evening; and, according
to the Mosaic law, both must bathe after the act of coitus. In the
_Koran_, also, intercourse is forbidden during menstruation, and until
the woman has been purified with water. The law’s of Islam demand from a
man who marries a virgin that he shall have intercourse with her the
first seven nights in succession; whilst he who marries a wife no longer
virgin, needs to visit her only the first three nights in succession.
Subsequently, during married life, the Mohammedan shall have intercourse
with his wife regularly once a week. Amongst many savage races,
intercourse is forbidden with a woman during pregnancy, the puerperium,
and lactation.
The first act of intercourse is difficult and painful to the virgin. At
times the rupture of the hymen is exceedingly difficult. Even after
this, it is some time before genuine pleasure is experienced in sexual
intercourse.
To the female, intercourse is harmful when performed with undue
frequency, or during menstruation, or indiscriminately throughout
pregnancy, or during the puerperium, or incompletely or in an unnatural
manner, or finally when performed in an unsuitable bodily attitude.
“Unduly frequent performance of the act of coitus,” writes _Hegar_,
“which is liable to occur either in marital or in illicit intercourse,
gives rise to anæmia, defective nutrition, muscular weakness,
intellectual and nervous exhaustion. Young and healthy individuals
recuperate rapidly after excesses of brief duration, as is often seen in
young married pairs. Sickly and elderly persons, on the other hand, are
much more severely affected by sexual excess, and recover therefrom but
slowly if at all. Long continued sexual excesses ultimately wear out
even the strongest.”
Intercourse effected by force, or with a girl of immature age, is
distinguished as rape, a punishable offence both in Germany and in
Austria. The offence is defined as extra-marital intercourse with a
female under the age of fourteen years, with or without the latter’s
consent; or extra-marital intercourse with a female of any age against
her will or deprived of the power of resistance—either by the use of
actual force, by the employment of threats, or by loss of consciousness.
With regard to the last specification, the law regards as rape
intercourse with a woman unable to resist through loss of consciousness,
whether that loss of consciousness is or is not produced by the direct
action of the violator.
In the female, the act of intercourse, alike physically, in its natural
consequences, and mentally, is at once more difficult and of more
enduring results than in the male. A writer of the new school, who
according to his own admission has no other interest than the study of
the sexual life, writes of himself: “I have often enough had intercourse
with members of the other sex, in a few cases, indeed, out of pure
inclination; but in all cases alike the aim and the result were the
same—as soon as I had gained my end, the affair was finished. Passion, a
bestial act, exhaustion, commonly a feeling of loathing; in the best
possible case a fugitive but not an agreeable memory; voilà tout.” To
women, such a description, happily, is applicable only in the most
exceptional cases.
With the completion of coitus, the voluntary and conscious action of the
two parties to the act is at an end; the subsequent stages of the
function of generation are independent alike of consciousness and will.
When complete intromission of the penis has been effected, and
ejaculation takes place, the semen is usually deposited at the os uteri
or in the immediate neighborhood of that orifice. During the act of
ejaculation, a peristaltic contraction of the vagina occurs, by means of
which the semen at the os uteri is subjected to a moderate degree of
pressure; the contraction and the pressure may perhaps persist for some
little time after the completion of the coitus. In rabbits on heat, such
contractions of the vagina, by means of which the semen was forced under
pressure into the interior of the uterus, have been actually observed.
During coitus, the uterine muscle is also active. During strong sexual
excitement, the uterus descends in the pelvis, the downward movement
being increased by the pressure on the woman’s abdomen. The os uteri
externum is drawn open, and the aperture, hitherto flattened, now
becomes rounded. At the same time, the secretion of the cervical glands
is expelled, and small quantities of semen are sucked into the cervical
canal. The _plicae palmatae_ offer a certain hindrance to the entrance
of the semen; but the surface of the interior of the canal is rendered
much smoother by the free secretion of mucus by the cervical glands.
Further, it appears highly probable that during the excitement of
coitus, the mouths of the Fallopian tubes, ordinarily more or less
tightly closed, become widely opened, so that the entrance of the
spermatozoa is favored.
The muscular movements of the uterus were observed by _J. Beck_ in a
woman suffering from prolapse. During sexual excitement, the os uteri
opened and closed rapidly five or six times in succession, remaining at
last firmly closed. Further, in bitches on heat, _Basch_ and _Hoffmann_
observed the vaginal portion of the cervix to descend in the vagina, the
os uteri opened, mucus was extruded, and the os was then retracted.
_Hohl_, _Litzmann_, and others have reported, that in women endowed with
great nervous susceptibility, friction of the vaginal portion of the
cervix with the finger arouses sexual sensation, with rounding of the os
uteri externum, descent of the uterus, and hardening of the vaginal
portion; this latter is regarded by _Graily Hewitt_ and by _Wernich_ as
a necessary accompaniment of copulation. _Henle_ believes that the
hardening and protrusion of the vaginal portion of the cervix are due to
a change in the tension of the delicate vessels of this structure, which
have an exceptionally thick muscular coat; _Rouget_ compares the
mechanism with that by which erection of the penis is produced. These
authors consider that sexual excitement is indispensable for the
erection of the vaginal portion of the cervix.
Thus, _Hohl_ writes: “Numerous observations have shown that in females
endowed with a considerable degree of nervous susceptibility, and
especially in nulliparae, during examination and during any increasing
irritation, not only is there an increased secretion of the vaginal
mucus, but also a momentary descent of the uterus and an opening of the
os uteri externum, so that this orifice has the appearance for the
instant of the open mouth of a tube.” _Litzmann_ reports that during the
vaginal examination of a young, extremely erethistic woman, the uterus
suddenly assumed a more vertical position, and came lower down in the
pelvis; at the same time, the lips of the cervix became equal in length,
the os uteri externum became rounded, soft, and penetrable by the
finger; whilst the breathing and the voice indicated the occurrence of
intense sexual excitement. _Rouget_ assumes that the body and the fundus
of the uterus constitute an erectile organ, which however possesses
capability for erection only during the period of ovulation; _Hewitt_,
on the other hand, considers it extremely probable that the erection may
occur at any time during sexual intercourse, whether ovulation is
proceeding or not. _A. Wernich_ considers, basing his views in part on
personal observations, that erection of the lower segment of the uterus
occurs, like erection of the penis, whenever a moderate degree of sexual
excitement is experienced; in women, however, he believes that erection
is seldom extreme, and that it declines with the other symptoms of
sexual excitement, viz., flushing of the face, moisture and glistening
of the eyes, peculiar groaning expiration, etc. Whereas during
ovulation, erection is merely a necessary concomitant of the other
menstrual processes; during coitus, erection not only occurs much more
powerfully, but it is also an important—perhaps the most
important—contributory factor in effecting fertilization.
It is no longer possible to accept the view of earlier physiologists
that the purpose of this erection of the lower segment of the uterus is
“to constitute with the penis a continuous canal between the male and
the female genital organs.” Contact between the glans penis and the os
uteri externum is not indeed an occurrence of extreme rarity; but, on
the other hand, it is in no sense a constant nor even a frequent
incident of sexual intercourse. It is ejaculation, especially, which is
subserved by the erection of the vaginal portion of the cervix. In the
female, ejaculation occurs at the moment of the most intense sexual
pleasure, and is marked by the evacuation from the os uteri externum of
a moderate quantity of mucous fluid with an alkaline reaction. In some
cases, in which a chronic discharge of this cervical mucus occurs, it
forms an elongated coagulum of delicate vitreous jelly, the
“mucus-string” of _Kristeller_. The last-mentioned author is of opinion
that the spermatozoa slowly, but by active movements, find their way
along this string into the cavity of the uterus. This assumption,
however, is met by _C. Mayer_ and _Marion Sims_ with the objection, that
_Kristeller’s_ observations were for the most part carried out on women
who were out of health, and that a gelatinous secretion of this
character obstructs the orifice of the cervical canal, and hinders the
occurrence of conception. From the erection of the portio vaginalis
during sexual excitement, and its sudden relaxation post cohabitationem,
_Wernich_ deduces the occurrence of a process of aspiration, by which
the semen is drawn up through the cervical canal into the cavity of the
uterus; a process which has been seen in actual occurrence in vivisected
animals. It is said that to many women this feeling of a process of
suction is so well known, that thereon, in association with the
consequent almost complete absence of mucus and seminal fluid from the
vagina, they are accustomed to base a belief that conception will occur.
It is said that this aspiratory activity on the part of the uterus may
be perceived during coitus by the male also (?). It is assumed by
_Grohe_ that the wave motion of the cilia of the epithelium lining the
cervical canal, is of importance in promoting the ascent of the
spermatozoa; it may be that the vibration of the cilia exercises a
motile stimulus on the spermatozoa, it may be that the continually
repeated stroke of the cilia serves to prevent the permanent
agglutination of the spermatozoa into groups.
According to _Sims_, the aspiratory action of the uterus is effected in
the following manner: By the contraction of the constrictor vaginae
superior muscle, the cervix is pressed downwards against the glans
penis, and by this pressure its contents are evacuated; the parts then
relax, the uterus suddenly returns to its normal state, and thus the
seminal fluid with which the vagina is filled is drawn into the interior
of the cervical canal.
_Eichstadt_ also attributes to the uterus an aspiratory force, dependent
upon coitus, and competent to force into the interior of the uterus the
semen ejaculated into the os uteri. The changes in the uterus which are
the necessary antecedents of this aspiration, namely, an engorgement
with blood whereby the flattened form of the uterus gives place to a
more rounded form, and the cavity of the organ is increased in capacity,
take place, in the opinion of this author, only when during intercourse
the woman has attained the acme of sexual gratification, by which alone
can the aforesaid change in the uterus be brought about. _E. Martin_ and
_Chrobak_ have also directed attention to the fact, that some importance
in this connexion must be attached to the facultative enlargement in the
size of the os uteri externum.
_Lott_, by his researches into the behaviour of the cervix uteri in
relation to the act of conception, is led to the conclusion that the
locomotive capacity of the spermatozoa forms the principal factor in
effecting a fertilizing contact between the spermatozoa and the ovum.
This locomotive capacity may be increased or diminished by a number of
conditions, among which the principal are: the activity of the cervix
uteri (the ciliated epithelium); the character of the secretions; and
the position, shape, and size of the cervix. Thus, this author
concludes, the part played in conception by the normal cervical canal is
a purely passive one, with the sole exception of the activity of the
ciliated epithelium—and the influence of this factor must be regarded as
extremely doubtful. That during ejaculation the external orifice of the
male urethra and the os uteri externum are in close apposition, is
denied by _Lott_, who adduces in support of his views data derived from
comparative investigations on various animals. In the dog, the
configuration of the genital organs is such that it is impossible to
suppose that any apposition can occur; the same is the case with the
sheep; and still more so with the rabbit, who possesses two quite
distinct portions vaginales, projecting freely into the vagina. In the
human species also, the character of the walls of the cervical canal,
where in the normal state the plicae palmatae may almost be said to
interlock, separated only by a thin stratum of mucus, offers a hindrance
to the entrance of the ejaculated semen by the direct force of
ejaculation itself. As regards the independent motile powers of the
spermatozoa, the researches of _Lott_ showed that not only can they
overcome strong capillary currents, and can traverse the width of a
coverglass (18mm.—about ¾ in.) in about five minutes; but further that
they are capable of migration through the finest interstices (those of
an animal membrane) provided that the fluid with which the membrane is
moistened is one favourable to their vital activity.
_Kehrer_, who in general supports the view that the _modus coeundi_ and
an active attitude on the part of the female have an important influence
on the occurrence of conception, assumes that independent contractions
of the cervix occur, whereby is expelled the delicate plug of mucus that
fills the cervical canal and offers an obstacle to the passage of the
spermatozoa. He believes that the duration of the act of intercourse,
the mechanical relations between the penis and the vagina, the activity
of the uterine muscle, the secretory activity of the utero-vaginal
mucosa during the act, and the posture of the female _post coitum_, are
all important factors in the occurrence of conception. Thus, he believes
that if during intercourse there is a failure of the uterine
contractions, which should expel the plug of cervical mucus, the semen
flows away without effecting fertilization; if an unsuitable posture is
assumed during intercourse the woman remains sterile, but can be
fertilized without difficulty by coitus effected in the proper manner.
_Haussmann_ has shown, that in the same woman, and in similar
conditions, spermatozoa will on one occasion be found in the cervical
canal, and on another occasion will not be found there; and he has
further shown, that in some women we fail to find spermatozoa in the
cervical canal in circumstances in which, in other women, we regularly
find them in that situation.
Far as we may be from a complete knowledge of the conditions upon which
conception depends, this at least is certain, that the passage of
spermatozoa through the os uteri externum is a sine qua non of
fertilization. Indeed, it would seem that we must accept as true the
assumption of _Meyerhofer_, that fertilization is possible only if the
semen passes at once into the cervical canal, mingles, that is, at once
with the alkaline cervical mucus—unless, indeed, the coitus takes place
during the catamenial flow, when the blood has neutralized the acid
reaction in the vagina, or takes place when some morbid condition has
had the same result. The theory of _Johann Müller_, regarding the
piston-like action of the penis during coitus, by which the semen is
actually forced through the cervix, must be rejected; equally unsound is
_Holst’s_ assumption that during intercourse the semen is ejaculated
through the enlarged cervical canal directly into the cavity of the
uterus. It would appear, however, to be a necessary condition of
fertilization, that the semen should be ejaculated into the uppermost
segment of the vagina, so that the fluid comes into actual contact with
the os uteri externum; it may be that the alleged aspiratory force of
the uterus then comes into play, by means of which the semen is sucked
into the cavity of that organ; it may be, on the other hand, that
_Beigel_ is right in his theory of the existence of a _receptaculum
seminis_, formed by the anterior and posterior lips of the cervix uteri
and the uppermost segment of the vagina—in this space, he supposes, a
part of the semen is retained in contact with the orifice of the
cervical canal.
It is, also, exceedingly probable that during coitus a reflex nervous
mechanism becomes active, by means of which the uterine orifices of the
Fallopian tubes are opened, the vaginal portion of the cervix descends
in the vagina, the os uteri externum enlarges, the orifice becoming
rounded where before it was flattened, and finally small quantities of
semen may be aspirated into the cavity of the uterus.
I further regard it as important in promoting conception, that
simultaneously with the changes above described, the reflex nervous
stimulation should lead to the secretion by the cervical glands of a
gelatinous material, alkaline in reaction, and therefore adapted to
increase the locomotive powers of the spermatozoa, so that these latter,
aided by the activity of the ciliated epithelium lining the cervical
canal, will gain the interior of the cavity of the uterus, and thence
pass onwards to the Fallopian tubes. The significance of the glands in
the mucous membrane lining the cervical canal has hitherto been
underestimated in this connexion.
Whereas in the primitive state of mankind, among savage races at the
present day, as among our own prehistoric ancestry, nakedness is the
rule, so also intercourse in these circumstances is effected altogether
without any regulation by law or custom, on the mere prompting of
unbridled natural passion, and, moreover, there is the fullest
promiscuity in sexual relations; but civilization has led man to impose
restraints upon sexual intercourse, and has introduced marriage as a
sacred institution. Among certain primitive peoples, however, among whom
the wives are common to all the men, transitory pairings nevertheless
occur, especially when a woman becomes pregnant; to cease, however,
during the period of lactation. “This is the origin of marriage, which
has evolved from rape and prostitution, as law has evolved from crime”
(_Lombroso_). This author makes an interesting observation when
describing the entire freedom of sexual intercourse that obtains among
the Red Indians of North America, to the effect that “often, times of
general promiscuity occur, as with rutting animals, generally in the
warm season of the year, when nutriment is abundant; it is difficult to
indicate any distinction between the tumultuous orgies of the baboon,
and those of the Australian Blackfellows, among whom the sexes keep
apart during the greater part of the year, to intermingle like rutting
beasts during the season of the yam-harvest.”
The paths of civilization, from the complete promiscuity of sexual
intercourse to the lofty ideal of life-long monogamic union, has not
been a straightforward one, but has been marked by various aberrations
of sexual relationship; hetairism, prostitution, polyandry, incest,
rape, the _jus primae noctis_, etc. The anthropologist is able to trace
the successive stages of the development of the institution of monogamic
marriage; the community of wives within the clan; free sale of wives and
daughters; bestowal of a man’s wife or concubine for the honour of a
guest; ritual prostitution for the honour of the gods and at numerous
religious festivals; æsthetic and literary hetairism, with bestowal of
favours according to free inclination; community of wives among all
males of the same family; the claim of the wife to as many as five or
six husbands; the right of brothers to their sisters; the defloration of
virgins by the priests in heathen temples; the temporary possession of
the wife by the chief of the community, prior to her possession by her
permanent husband; defloration of the bride by the bonze before her
marriage; the feudal right of the mediæval seigneur to the _prima nox_
of the bride of his retainer.
In the lower stages of civilization, copulation appears so natural an
action that it is performed in public entirely without shame. Thus,
_Cook_, in his first voyage, describes having seen an indigen engage in
sexual intercourse with a girl of eleven years, under the very eyes of
the queen, with whom _Cook_ was then having audience; the sexual act
was, according to _Cook_, the favourite topic of conversation between
the sexes. _Herodotus_ reports that many peoples of antiquity had no
regard for privacy in sexual intercourse, but that, like the lower
animals, they had connexion in any company. In the _Bible_, also, it is
recorded that sexual intercourse was practised in public: “So they
spread Absalom a tent upon the top of the house; and Absalom went in
unto his father’s concubines in the sight of all Israel.” (II. _Samuel_,
XVI. 22.) According to _Athenaeus_, the Etruscans, at their public
banquets, were equally unrestrained. _Plutarch_ reports that among the
Spartans the maidens and the young men went about naked together. Even,
indeed, after the sense of modesty had begun to develop, it was long
before any secret was made about the act of intercourse. In classical
antiquity, it was very frequently the subject of pictorial and plastic
representation. Even in more recent days, there have been artists who
have not hesitated to depict the sexual act: thus we have the _Venus
with a Faun_ by _Caracci_; the _Jupiter and Io_ of _Correggio_; the
_Leda and the Swan_ of _Tintoretto_; and similar pictures by _Luca
Giordano_, _Rubens_, _Titian_, and _Franceschini_.
Even in the early centuries of the Christian era, the sect of the
Adamites practised intercourse openly in the light of day, on the ground
that that which was right in the dark, could not be wrong in the light.
The same is reported of the sect of Turlupins, in France in the
fourteenth century. We cannot refrain from quoting at length from
_Lombroso_ and _Ferrero_ a passage relating to the evolution of sexual
manners in the female sex (_Woman as Criminal and Prostitute_): “In the
lowest stages of development, the feeling of modesty is entirely
wanting; limitless freedom in sexual intercourse is the general rule;
and even where no system of promiscuity prevails, marriage rather
fosters than discourages prostitution, especially in countries in which
husbands are accustomed to expose their wives for sale. This fact may be
brought into relation with the well known lasciviousness of apes and
other animals high in the scale, showing that sexual excitability
increases _pari passu_ with intelligence, so that to man it is as
impossible as to an ape to satisfy his sexual needs with a single
female. Whilst among the apes, a single male possesses a number of
wives, we find in the gregarious life of primitive man that community of
wives has taken the place of polygamy, which institution, however,
reappears in a higher stage of culture for the benefit of the more
powerful masculine natures.
“To the dominion of prostitution as a normal institution succeeds the
period in which it persists as a variously metamorphosed survival: it
may be as the duty of the wife to surrender her person to any other
male of the same family; or the woman may have to bestow her favors on
a religious or political chief, as in the institution of
temple-prostitution, where the wife must give herself, it may be to
any one and at any time, or it may be to defined persons only and at
stated festivals. Frequently we meet with another development of
prostitution, finding that while the wife must remain chaste, the
unmarried woman is allowed unrestricted intercourse; or, again, the
wife at certain definite periods may dispense with fidelity to her
husband, and return to the primitive condition of promiscuity. In
certain instances prostitution is combined with the duties of
hospitality, and marriage, though approximating to the monogamic
ideal, must tolerate the intrusion of the guest into the marriage
bed.”
“In a third period, prostitution no longer fills the place of a
traditional survival, but is a morbid manifestation confined to a
certain class of the community. But bridging this transition of
prostitution from a normal to a morbid manifestation, we have the
remarkable phenomenon of æsthetic prostitution. Thus, in India and in
Japan, an agreeable class of prostitutes practices the arts of singing
and dancing, and forms a privileged caste; similarly, in the most
flourishing period of Grecian culture, the leading men of the time
formed a social circle around the hetairæ, from whom they derived a
fruitful stimulus to intellectual and political activity. In this
respect, history repeated itself in Italy in the sixteenth century.
Alike in classical Greece and in mediæval Italy, this æsthetic
prostitution fanned the flames of a period of intense spiritual
activity—for in individuals as in races, intellectual quickening is ever
accompanied by erotic excitability.”
The unbridled passion of the primitive races of mankind, the coercive
love of beauty felt by the ancient Greeks, the swelling flood of erotism
of the great mass of people of all times, is gradually guided into the
quiet channel of the marriage bed; and even though monogamic marriage is
incapable of fully providing for all manifestations of sexual passion,
still, from the medical point of view, we must maintain that marriage is
for women the most hygienic and the most proper means of gratification
of the sexual impulse.
_Conception._
The union between ovum and spermatozoön, whereby fertilization is
effected, appears to occur in the human species as a rule in the outer
third of the Fallopian tube, the ampulla of this structure
(_receptaculum seminis_ in _Henle’s_ terminology) serving to store the
semen for a considerable period; in the lower animals, the usual
occurrence of fertilization in this region has been established by
direct observation. The open mouth of the tube receives the mature ovum,
guided thither from the ovary by appropriate movements of the ovarian
fimbriae; these movements have been seen in active occurrence in the
guinea pig by _Hensen_. Once within the tube, the onward movement of the
ovum is effected by the cilia of the epithelium lining of the canal.
_His_ has formulated the theory that in the human species fertilization
is possible only in the uppermost segment of the tube; an assumption
that is probable enough, but cannot be regarded as definitely
established. An analogy certainly exists among the lower divisions of
the animal kingdom, for _Coste_, _His_, and _Ohlschläger_ have proved
that an ovum which passes through the Fallopian tube without being
fertilized, undergoes notable alterations. Further, _Coste_ has shown,
in the case of the ovum of the domestic fowl, that this is no longer
capable of being fertilized after it has passed through the upper
segment of the oviduct. Other authorities, however, namely _Löwenthal_,
_Mayrhofer_, and _Wyder_, oppose the extension of this rule to the human
species. _Löwenthal_ assumes that in the human female, fertilization
ordinarily occurs in the cavity of the uterus, in the wall of which the
unfertilized ovum has already embedded itself; and he supports his
contention by the statement that spermatozoa are not to be found in the
Fallopian tubes or on the surface of the ovaries. _Mayrhofer_ and
_Wyder_ point out that the movement of the cilia of the ciliated
epithelium is in the interior of the uterus in an upward direction, but
in the Fallopian tubes is downwards in the direction of the uterus.
The contention of _Löwenthal_ was disproved by _Birch_ and _Hirschfeld_,
who, in a prostitute dying during the act of intercourse, found, fifteen
hours after death, living spermatozoa in the Fallopian tubes. On the
other hand, more recent investigations, those, for instance, of
_Hofmeier_, _Mandl_, and _Bonn_, have confirmed the data given above
with regard to the direction of the ciliary movement in the interior of
the genital passages. Moreover, _O. Becker_ has shown that the ciliated
epithelium of the tubes extends over the fimbriae and even on to the
adjoining pavement epithelium of the peritoneum; and he believes that
the ciliary movement of this region keeps up a constant current, the
purpose of which is to sweep the ovum into the ostium of the tube, and
thence down towards the uterus. _Lode_ has adduced positive experimental
evidence of the occurrence of such a movement of translation.
The general result of anatomical investigation is, that the conjugation
of the ovum with the spermatozoön takes places in the ampulla of the
Fallopian tube; but it is established that fertilization may also take
place lower down in the tubes, or in the uterine cavity, or even on the
surface of the ovary, _i. e._, in the abdominal cavity.
The fertilization of the mature ovum—maturation having occurred within
the ovarian follicle before its rupture—has been shown by numerous
researches on the ova of other animals to consist in the fusion of the
male and the female nuclear substance; and it appears that of the
enormous number of spermatozoa, estimated by _Lode_ at 226 million at a
single ejaculation, that enter the female genital passage, but a single
one penetrates the ovum. Towards the head of this spermatozoön there
extends from the surface of the ovum a process, flat at first, but
becoming more and more prominent, until it surrounds the head, and fuses
with it. The motile tail of the spermatozoön disappears, whilst the
head, which has now passed through the vitelline membrane and entered
the ovum, assumes the appearance of a nucleus, and is called the _male
pro-nucleus_. The original nucleus of the ovum has previously prepared
itself for fertilization by the extrusion through the vitelline membrane
of portions of its substance (known as _polar globules_), and now
constitutes the _female pro-nucleus_. Towards this latter, situated
somewhere near the centre of the cell, the male pro-nucleus continues to
move, the vitelline granules meanwhile being disposed round about it in
radiating lines, forming a star-shaped figure. Having come into contact,
the two pronuclei fuse completely to form a new nucleus, the nucleus of
the now fertilized egg-cell. The result of fertilization is the
formation of the first _segmentation-sphere_, from which, by further
subdivision, the new individual is formed. Thus is effected that which
_Hippocrates_ describes in the words: “The seed possessed both by man
and by woman, flow together from all parts of the body; the fruit is
formed by the mingling of the two seeds.”
[Illustration:
FIG. 55A.—First Stage. FIG. 55B.—Second Stage.
Entrance of a spermatozoon into the ovum of ascaris megalocephala.
After preparations by M. Nussbaum. (Half of the ova only are
depicted.)
]
[Illustration:
FIG. 56.—Ovum of Asterakanthion ten minutes after fertilization.
]
[Illustration:
FIG. 57.—Fusion of male pro-nucleus and female pro-nucleus to form the
segmentation nucleus of the fertilized ovum.
]
The most favourable period for the occurrence of fertilization appears
to be when intercourse takes places from eight to ten days after the
termination of the menstrual flow. In 248 instances in which the date of
the fruitful coitus was exactly known, it was ascertained by Hasler that
in 82½ per cent. of all cases, conception was effected in the fourteen
days succeeding the menstrual period. In general it may be stated that
the theory of the periodicity of ovulation and of the causal relation of
this process to menstruation, has not been shaken by the result of
researches recently undertaken by opponents of that theory; hence it
appears that the fertilized ovum is the ovum of the last completed
menstruation.
Already in the writings of the old Indian physician _Susruta_, we find
expression of the view that the period that immediately succeeds the
cessation of the menstrual flow is one most favourable to conception.
“The time of generation,” he says, “is the twelfth night after the
commencement of menstruation.” In the Jewish _Talmud_, the day before
the onset of menstruation, and the days immediately succeeding the
cessation of the flow, are indicated as those most favourable to the
occurrence of conception; moreover, in the _Talmud_, notwithstanding the
fact that intercourse during menstruation is prohibited on pain of
death, and that coitus is not regarded as permissible until the lapse of
twelve clear days after the cessation of the flow, nevertheless the
assertion is made that intercourse during menstruation may lead to
conception.
[Illustration:
FIG. 58. —Passage of spermatozoon through the zona pellucida of the
ovum of asterakanthion.
]
[Illustration:
FIG. 59.—Ovum of scorpæna scrofa thirty-five minutes after
fertilization.
]
[Illustration:
FIG. 60.—Male pro-nucleus and female pro-nucleus in fertilized ovum of
frog, prior to the formation of the segmentation nucleus.
]
_Hippocrates_ writes: _Hae nempe post menstruam purgationem utero
concipat_. _Aristotle_ says: _Plerasque post mensum fluxum nonnullas
vero fluentibus adhuc menstruis_. _Galen_ writes: _Hoc autem
conceptionis tempus est vel incipientibus vel cessantibus menstruis_.
_Soranus_ writes to a similar effect: Just as the soil is suitable only
at certain seasons for the reception of the seed, so also in the human
race intercourse does not always take place at a time suited for the
reception of the semen. To be effective, coitus must occur at the proper
time.... The act of intercourse that is to lead to conception may best
occur either just before or just after the menstrual flow, when,
moreover, there is strong desire for the sexual embrace, and neither
when the body is fasting, nor when it is full of drink and undigested
food. The time before menstruation is, however, unsuitable, for then the
womb is heavy from the flow of blood, and two conflicting tendencies
will come into operation, one for the absorption of material and the
other for its outflow. During menstruation, again, conception is
unlikely to occur, for then the semen is wetted and washed away by the
flowing blood. The sole proper time is that immediately after the flow,
when the womb has freed itself from its humours, and warmth and moisture
stand in harmonious relationship.
Among many of the castes of Hindustan, it is a religious ordinance that
on the fourth day of menstruation a man shall have intercourse with his
wife, “since this day is that on which conception is most likely to
occur.” Indian physicians advise, in order to bring about conception,
“that coitus be effected always as soon as the menstrual flow has
ceased, at the end of the day, and when the lotus has closed.” In Japan,
medical opinion is to the effect that a woman is capable of conceiving
during the first ten days after menstruation, but not later (_Ploss_ and
_Bartels_).
The view that the first days of the intermenstrual interval are those
most favourable to the occurrence of conception, is further confirmed by
the statistical data collected by _Löwenfeld_, _Ahlfeld_, _Hecker_, and
_Veit_; and it appears that as the date of the next menstruation is
approached, there is a continual decline in the frequency of conception;
just before the flow, conception hardly ever occurs. _Hensen_, from the
records of 248 conceptions in which the date of the fruitful intercourse
was exactly known, draws the following conclusions:
1. The greatest number of conceptions follow coitus effected during the
first days after the cessation of the menstrual flow.
2. When coitus is effected during menstruation, the probability of
conception increases day by day as the end of the flow is approached.
3. The number of conceptions following coitus effected shortly before
menstruation is minimal.
4. However, there is no single day either of the menstrual flow or of
the intermenstrual interval, on which the possibility of the occurrence
of conception can be excluded.
_Feokstitow_ has drawn up from statistical data an ideal
“conception-curve,” which teaches that conception most readily ensues
upon coitus effected soon after the end of the menstrual flow, in the
first week, that is to say, of the intermenstrual interval; moreover,
the curve shows that the highest percentage of conceptions occurs on the
very first day after the cessation of the flow, and that after this day
the percentage of conceptions declines. The percentage frequency of
conceptions from coitus effected on the last day of menstruation, and on
the first, ninth, eleventh, and twenty-third days, respectively, of the
intermenstrual interval, is expressed by the ratio 48 : 62 : 13 : 9 : 1;
and between the points given, the course of the curve is almost
rectilinear. The probability of the occurrence of conception on the
twenty-third day of the interval (on which day the curve reaches its
lowest point), is one-sixty-second of the maximum probability.
The proper performance of coitus depends upon the _potentia coeundi_ of
the male; the attainment of conception depends upon his _potentia
generandi_. The _potentia generandi_ demands from the man the functional
competence of the testicles, the perviousness of the seminal passages
(namely, of the vasa deferentia and the urethra), the secretion of a
normal semen, and, finally, a proper formation of the penis, whereby
during ejaculation the semen may be deposited in sufficient proximity to
the os uteri externum.
Normal semen is a whitish, semi-transparent fluid, of the consistency of
thin cream. It contains aggregations of a nearly spherical shape,
consisting of a vitreous, transparent, colourless or light yellow,
gelatinous, elastic substance. Under the microscope this substance has a
hyaline appearance, and exhibits in its interior innumerable clear
spaces of varying size, which are apparently filled with a clear fluid.
Not infrequently, these spaces are extremely narrow and therewith
greatly elongated and disposed in parallels, so that the whole substance
thus obtains a striated appearance. When treated with water, this
material becomes whitish and non-transparent, and assumes under the
microscope a finely granular aspect. When allowed to stand without
agitation for twenty-four hours, this substance dissolves and becomes so
intimately mingled with the seminal fluid that it can no longer be
clearly differentiated therefrom. In all probability it is merely a
secretory product of the seminal vesicles.
The truly fluid portion of the semen contains the following
morphological elements: