PHYSIOLOGY OF THE UTERUS AND OVARIES.
Menstruation is a periodical flow of blood having its source in the
walls of the uterus. But menstruation is excited by and dependent upon
ovulation, and the effective cooperation of both the uterus and ovaries
is necessary to both menstruation and conception. We shall consider
these functions separately.
MENSTRUATION.
In healthy women at the period of puberty, a certain amount of
sanguineous fluid is secreted by the lining membrane of the uterus, and
is excreted through the vagina every month; this is termed the
catamenia, or menses, and the function itself menstruation. A female in
whom the discharge recurs at the usual periods, in the usual quantity,
and of the usual quality, is said to be regular, The occurrence of
menstruation defines the period of puberty at which a girl becomes a
woman capable of conception, and its cessation terminates the prolific
period of female life.
Dr. Robinson, of Manchester, England, in a paper on the natural history
of menstruation, has stated the age at which it occurred in 450 cases.
According to his table, 10 menstruated for the first time at 11 years of
age, 19 at 12, 53 at 13, 85 at 14, 97 at 15, 76 at 16, 57 at 17, 26 at
18, 23 at 19, and 4 at 20.
The time at which the first menstruation occurs varies exceedingly from
the influence of climate, habits of life and constitution. There have
been occasional instances of very precocious menstruation, in which the
first appearance of the discharge was attended with all the attributes
of puberty. I myself knew one case where a girl of nine years, not only
menstruated, but presented the external signs of puberty, such as
prominent breasts, wide pelvis, rounded contour of body, &c.
The first appearance of the menses very rarely occurs without being
preceded by premonitory symptoms. There is usually a degree of languor
and lassitude, fatigue after exertion, inequality of spirits, dark shade
under the eyes, headache, sometimes pain in the thyroid gland, pain in
the back, a sensation of tension and swelling in the lower part of the
abdomen, and occasionally considerably fever. Not unfrequently strange
nervous disturbances occur; but all of these symptoms may pass off, the
first and second time, without the appearance of the menses, or with a
white discharge only. Usually the phenomena may last from one to eight
days, then there is an abundant flow of mucus, which after one or two
days is mixed with blood, and soon gives place to almost pure blood.
When this discharge takes place most of the unpleasant symptoms
disappear, and the female only complains of weakness and is somewhat
pale. The hemorrhage continues for several days, then the amount of
blood mingled with the vaginal mucosities diminishes, soon there is
mucus alone, then the discharge ceases.
I should remark now that the propriety of applying the terms, blood or
hemorrhage, to the menstrual secretion is properly questioned.
Sometimes the first menstruation takes place without being preceded by
any discomfort, but pretty generally there is a change in the girl at
the time, both in her body and mind, a change that fits her for the
important duties that devolve upon her.
Most young girls have a return of the discharge after a month, the
menses afterwards recurring regularly; some do not become regular until
after several months. Sometimes the function is imperfectly performed;
such cases are accompanied with considerable distress.
In some young girls the precursory symptoms of the first appearance of
the menses may not be followed by a flow of blood, and there is an
apparent effort of nature recurring monthly for several months before
the courses become established.
There are occasional examples of retarded menstruation. I am acquainted
with one woman who at the age of twenty-five years has not menstruated.
The absence of the menses does not render conception impossible, in
every case.
After the menses are established, until the time of their cessation,
they generally return every month, unless interrupted by pregnancy or
nursing. The average of the catamenial period is about twenty-eight
days; in a large number it is thirty days; in some instances they recur
every fifteen days.
The duration of the flow varies from one to eight days; three or four
days is the most usual duration. The quantity of blood lost is variable;
from three to five ounces is said to be the average.
When the ovaries are congenitally absent, or have been removed, or have
become disorganized, menstruation is absent, or ceases. The cause of the
menses is the successive evolution of the Graafian vesicles; but the
regular process may go on in the ovary without the regular sanguineous
discharge.
The menses continue in the majority of cases until about the age of 46
years, or perhaps in this country 48 years.
According to Dr. Robertson, of England, the periods at which it closed
in 77 individuals was, in 1 at the age of 35 years, 4 at 40, 1 at 42, 1
at 43, 3 at 44, 4 at 45, 3 at 47, 10 at 48, 7 at 49, 26 at 50, 2 at 51,
2 at 52, 2 at 53, 2 at 54, 1 at 57, 2 at 60, and 1 at 70.
The average duration of the menstrual function is about 30 years. The
cessation of the ovarian function is generally announced several years
in advance by irregularities of the menses. Besides the intermissions
and irregularities, there are other symptoms; a general and indefinite
feeling of uneasiness, pelvic pains, itching at the genital parts,
flashes of heat in the face, alterations of chilliness and perspiration,
leucorrhœa, etc. These troubles are usually slight, and disappear
promptly. The time of life has been called the CRITICAL PERIOD, because
there has been an opinion prevalent that peculiar dangers attend it.
However, the mortality is not greater between the ages of 45 and 50
years than at any other period of life. Yet it is true that in some
instances diseases that had been latent previously, declare themselves
at this period.
THE FUNCTION OF THE OVARIES.
We will now consider the physiological action of the ovaries and its
intimate connection with the action of the uterus in menstruation, etc.
Preceding the first menstruation an ovary is considerably enlarged,
becomes of a red color, and its vascular apparatus is considerably
congested; the Fallopian tube also becomes congested; its fimbriated
extremity is of a violet red color, and has a velvety appearance. The
Graafian vesicles increase in size; fifteen or twenty of them, more
advanced than the others, project from the surface of the ovary; one of
these grows so that after a few days it forms a tumor of the size of a
cherry; the walls of the vesicle, being distended by an increased
secretion of fluid, becomes quite thin, and at last are ruptured. When
the thinned walls give way, the ovule is expelled, with a part of the
granular contents of the vesicle; these are grasped by the fimbriated
extremity of the Fallopian tube which is prepared to receive it and
convey it through its canal into the cavity of the uterus.
This evolution of an ovule excites numerous sympathies throughout the
organism of the female, and especially the generative organs. The
vascular apparatus of the womb becomes developed in an unusual manner; a
network of fine blood vessels surround the orifices of the numerous
glandular tubes, of which the membrane is almost entirely composed; this
gives a violet hue to the internal surface of the womb; the utricular
glands increase in size, the muscular structure of the uterus acquires
greater extension, becomes redder and more spongy and supple, the volume
of the organ is increased, the neck is tumefied and its orifice
narrower, the lips of the os tincæ are warmer and their color deeper.
The vascular congestion which the uterus undergoes is accompanied with
the exudation of sanguineous fluid, which is at first but a few drops;
this communicates to the increased vaginal mucus a reddish hue. After a
day or two there is a bloody flow from the vascular network of the
mucous membrane. This flow, which constitutes the menses, is diminished
after three or four days, and the discharge again contains a large
proportion of mucus and serum. It is probable that the rupture of a
Graafian vesicle occurs during the last days of the flow, ordinarily,
and it is also believed that venereal excitement is capable of exerting
so much influence upon it that it may determine the rupture of an
enlarged vesicle, which, without sexual intercourse, would have remained
whole several days longer.
After the discharge of the ovule consequent on the rupture of the
Graafian vesicle, the walls of the vesicle contract on the matter that
is effused within it, and form a compact mass, which after a time has an
orange yellow color—this is called the _corpus luteum_.
Ordinarily, in the human female in the normal condition, a new Graafian
vesicle increases in size every month, becomes excessively developed,
and finally bursts and discharges its ovule, to become, through
successive transformations, the _corpus luteum_. What is called the
“monthly sickness,” “monthlies,” “courses,” etc., never occurs without
having been preceded and accompanied by the development of a Graafian
vesicle.