NORMAL PREGNANCY
The entire body participates in the changes brought about by pregnancy.
The hips and breasts become fuller, the back broadens, and the woman
puts on fat. She becomes mature in appearance, but, of course, the
phenomena connected with alterations in the breasts and genitals are
most important, and late in pregnancy, most conspicuous.
The uterus exhibits the most marked alteration. From an organ that
weighs two ounces, it becomes the largest in the body, and increases in
size from two and one-half or three inches to fifteen inches. The
typical pear-shape becomes spheroidal near the end of the third month,
becomes pyriform again at the fifth month, and continues thus until
term.
Up to the fourth month the walls become thicker, heavier and more
muscular, but as pregnancy advances, more and more tissue is demanded,
until at the end, a muscle wall of only moderate thickness protects the
ovum. Meanwhile the muscular functions of contractibility and
irritability are greatly increased.
At the fourth month the womb, which has occupied a position of
anteversion against the bladder, rises out of the pelvis. It is now an
abdominal organ and as it gets heavier and heavier, it rests a certain
amount of its bulk on the brim of the pelvis. About the sixth month, the
uppermost part of the uterus (fundus) is at the level of the umbilicus.
At the eighth month, the fundus is found a little more than midway
between the umbilicus and the ensiform cartilage. About two weeks before
term, it reaches its highest point, the ensiform cartilage, and then
sometimes sinks a little lower in the abdomen.
The ovum, or egg, does not completely fill the uterine cavity at first,
but grows from its side like a fungus until the third month. Then the
uterine cavity is entirely occupied and thereafter the egg and the
uterus develop at an equal rate. As the uterus rises in the abdomen, it
rotates to one side, usually the right, forward on its vertical axis.
[Illustration: Fig. 24.—Gravid uterus at the end of the eighth week.
(Braune.)]
The blood vessels and lymphatics also increase in size, number, and
tortuosity. Many of the veins become sinuses as large as the little
finger. This increased amount of fluid both within and without the
uterus has a marked effect upon its consistency. The walls of the
uterus, vagina, and cervix become softened, infiltrated and more
distensible. There is also an increase in size and in number of the
muscle cells.
During pregnancy the uterine muscle exhibits a definite functional
activity. Intermittent contractions occur, feeble at first, but growing
markedly stronger as pregnancy advances. These are the contractions of
Braxton Hicks. They are irregular and painless, but can be felt by the
examining hand. At term they merge into, and are lost in, the regular,
painful contractions of labor.
The breasts can not be said to be fully developed until lactation has
occurred, nevertheless, the glands show pronounced changes as a result
of marriage and pregnancy.
The size of the gland, as well as the size and appearance of the nipple
and areola, varies greatly in different women; but under the stimulation
of pregnancy the whole gland enlarges, including the connective tissue
stroma.
About the fourth month a pale yellow secretion can be squeezed from the
nipple. This is called _colostrum_. The pigmentation extends over a
wider area and deepens in color, while the increased vascularity is
shown by the appearance of the blue veins under the thin tender skin.
Light pinkish lines sometimes radiate from the nipple. These are striæ
and are more evident in blondes.
The milk comes into the breasts about the third day after labor, and
normally continues to flow for six, to ten or twelve months.
Why the pregnancy and labor induce such marked mammary activity is not
known, but the fact is patent.
=The skin= reacts both mechanically and biologically to the stimulus of
pregnancy.
[Illustration: Fig. 25.—Striæ Gravidarum. (Edgar.)]
_Striæ Gravidarum._—Striæ gravidarum appear on the abdomen similar to
those observed on the breasts and are due to the same cause—mechanical
stretching. When fresh, they are pinkish in color and variable in length
and breadth, but attain the greatest size below the umbilicus.
Occasionally they extend to the thighs and buttocks.
After labor, they become pale, silvery, and scar-like and are called
linea albicantes. They are sometimes found in other conditions than
pregnancy, such as tumors or ascites.
_Increased Pigmentation._—Pigmentation is not limited to the breasts. On
the abdomen, a dark line will appear between the umbilicus and the
pubes. This is the linea nigra, and it becomes most conspicuous in the
latter half of pregnancy. In the groins, the axillæ, and over the
genitals, the deposit is common, and sometimes patches appear on the
face, either discrete or in coalescence, to form a continuous
discoloration, called chloasma; or when extensive, the “mask of
pregnancy.” The pigmentation is absorbed, or at least greatly
diminished, after labor. The sebaceous and sweat glands are more active.
_The hair_ may fall out and the teeth decay. “With every child a tooth,”
is the cry of tradition. These changes are due to imperfect nutrition,
or to the presence of toxins in the circulation.
_Eruptions_ of an erythematous, eczematous, papular or pustular type are
not uncommon; and itching, either local or general, may make life
miserable.
=The blood= undergoes certain modifications that are fairly constant.
The total amount is increased, but the quality is poorer, especially by
an increase in water and white cells and a diminution of red cells. The
amount of calcium is slightly increased and the fibrin is diminished up
to the sixth month, when it rises to normal again at term.
=The heart= is slightly hypertrophied on the right side and blood
pressure somewhat raised. A marked increase in blood pressure is
suggestive of eclampsia.
=The thyroid gland= enlarges frequently, both as a consequence of
menstrual irritation and of pregnancy. Goiters may show an increase of
development, which remains after labor.
=The urine= is diminished in amount, but increased in frequency of
evacuation. The bladder is more irritable during the first and last
months, and micturition may be painful and unsatisfactory. The kidneys
must be watched carefully during gestation.
=The nervous system= is disordered in most women, but especially in
those of neurotic tendencies.
Irritability, insomnia, neuralgia of face or teeth, or perversion of
appetite in the so-called “longings” are the more common manifestations.
Cramps occur in the muscles of the legs, owing to varicose veins or
pressure upon the lumbar and sacral plexus of nerves.
=The lungs= are crowded by the growing uterus and the respiration
interfered with.
=The liver= is enlarged, but functionally it is less competent, and
constipation is common.
It is probable that most of the changes enumerated above are due to the
circulation through the body of some definite product of fœtal activity,
which is more or less toxic in character. The more pronounced effects of
this toxin will be studied under the abnormal conditions of pregnancy.
Generally, if the pregnancy is normal, the whole body responds to the
stimulating influence. After the nausea and vomiting of the early months
subside, the woman feels energetic and ambitious. She is eager to do
something at all times and feels fatigue but slightly. Music, literature
or housework engages her attention and is zealously and joyfully
practiced. The world seems bright and the thought of her labor does not
bring solicitude, but pleasant anticipations. The body fills out in all
directions and the woman takes on the appearance of maturity.
DIAGNOSIS OF PREGNANCY
The presence of pregnancy is naturally determined by the recognition of
those changes in the maternal system which the growing ovum produces.
During the _second half_ of the period the fœtus can be made out
distinctly by palpation, or by its movements, and the heart tones
observed by auscultation.
During the _first half_ this is impossible and the diagnosis must be
made from subjective symptoms elicited from the patient and upon
physical signs observed by the physician.
It is of extreme practical importance to be able to recognize a
pregnancy at all periods. The _subjective symptoms_ of the first half
are—amenorrhœa, morning sickness, irritability of the bladder,
discomfort and swelling of the breasts, enlargement of the abdomen and
quickening; but the appearance of any or all of these phenomena is not
to be regarded as conclusive, but merely as a presumption that pregnancy
exists. Either through ignorance, intent to deceive, or from
pathological conditions, any or all of these symptoms may be present,
but not until the tenth week are the changes in the uterus sufficiently
definite to confirm a diagnosis unless the circumstances are especially
favorable.
=Amenorrhœa.=—Cessation of the menses is practically invariable in
pregnancy. One or two periods may occur after conception, but care must
be used to exclude other causes of hæmorrhage. Sudden cessation of the
periods in a healthy woman of regular habits who is not near the
menopause, is strongly suggestive of pregnancy. Why a developing ovum
causes an immediate arrest of menstruation is not understood.
Amenorrhœa may occur in consequence of chlorosis, heart disease,
hysteria, tuberculosis, fright, grief, and some forms of insanity; a
change from a low to a high altitude, or an ocean voyage not
infrequently causes the flow to remain absent for one or more months. In
addition to its value as a presumptive symptom, the amenorrhœa affords a
common and convenient method of estimating the date of confinement. The
method is fallacious but practical, and will be discussed later.
=Morning Sickness.=—This symptom is not invariable. It is most frequent
in primiparas, but not so likely to occur in subsequent pregnancies. It
usually appears about the second month, shortly after the first period
missed. It varies in intensity. Some women have a little nausea on
arising and no further trouble during the day, others are nauseated and
vomit either on rising or after the first meal, and yet others after
each meal; but the general health is not ordinarily affected and the
tongue remains clean. Some cases are of extreme severity (hyperemesis)
and will be discussed elsewhere.
The morning sickness is probably toxic in origin. It must be remembered
that chronic alcoholism is accompanied by morning sickness, but with it
the tongue is furred.
=Irritability of bladder= is shown by a frequency of urination. It is
caused by the congestion and stretching of the tissues that lie between
the uterus and bladder and hold them in relation to one another. After
the third month an accommodation is established and the symptom does not
reappear until late in pregnancy, when the pressure of the heavy uterus
tends to keep the bladder empty. If especially annoying, this
irritability may be much relieved by putting the patient in the
knee-chest position night and morning.
=Enlargement of the breasts= is common in primiparas, but this, with
changes in the areola, may occur at menstrual periods in nervous women.
Tingling, pricking and shooting sensations may also be noted.
=Enlargement of the abdomen= is only noticeable toward the latter part
of the first half, when the uterus rises out of the abdomen.
=Quickening= means “coming to life,” and refers to the first movements
of the fœtus that are felt by the mother. It is described as similar to
the flutter of a bird in the closed hand. It is sometimes accompanied by
nausea and faintness. Quickening usually occurs about the seventeenth
week of pregnancy, and continues to the end. Gas in the intestines will
sometimes simulate quickening.
The movements are important in the second half as indicating that the
child is alive.
=Physical Signs.=—During the first weeks no conclusive changes occur
that can be detected by examination, and unless conditions are
especially favorable, the earliest time for the definite diagnosis of
pregnancy is the eighth week. Previous to this it is presumptive only.
At the eighth week, the breasts may show enlargement and tenderness,
with some secretion. In the multipara, this sign has no significance.
Secretion is present sometimes in the breast of nonpregnant women with
uterine disease (fibroids).
Examination of the abdomen at this time is of little value, but changes
in the uterus can be detected by careful bimanual examination. It is
needless to say that all internal examinations should be made with the
utmost care and gentleness.
Softening of the lips of the os (Goodell’s sign) may be found, but it
must not be confused with erosions of the os. The os of a nonpregnant
woman feels like the tip of the nose, and that of the pregnant woman
like the lips.
[Illustration: Fig. 26.—Bimanual examination. (Edgar.)]
The increased size and globular shape must also be considered as
confirmatory.
=Hegar’s Sign.=—The upper part of the uterus is soft and distended by
the ovum, the lower part is soft and not filled out by the ovum. Between
the two is an isthmus that is compressible between the fingers of one
hand in the vagina, and of the other upon the abdomen. When found, this
sign is of great value.
At the eighth week, pregnancy can be regarded as highly probable by the
conjunction of the following symptoms and signs: Amenorrhœa, morning
sickness, irritability of bladder, slight breast changes in primiparas,
lips of os externum softened, uterine body enlarged, softened, and
nearly globular in shape, and Hegar’s sign.
=Abderhalden’s test= is a serum reaction based on the well established
principle that the introduction into the blood of an organic foreign
substance leads to the formation of a ferment to destroy it.
Abderhalden’s plan was to discover whether the blood of a pregnant woman
contained a ferment capable of destroying placental protein. It is a
very complicated test, and subject to many inaccuracies and numerous
sources of error. At the same time, the main features of this reaction
have been confirmed, and when it is worked out, it will be of immense
value not alone in early uterine pregnancies, but in extrauterine
pregnancy. This view very properly demands that pregnancy be regarded as
a parasitic disease. It is practicable as early as the sixth week to
make a diagnosis, and it only fails in possibly ten per cent of the
cases. The negative test is equally definite as eliminating pregnancy.
=Sixteenth Week.=—Morning sickness and urinary symptoms have disappeared
but amenorrhœa remains. Enlargement of the breasts is noticeable, as
well as the increased pigmentation. The uterus begins to rise above the
symphysis as an elastic, somewhat ill-defined, boggy mass. The cervix is
softer. The characteristic dull lavender coloration of the vulvar mucous
membrane is now evident. It is due to the congestion and is called
Jacquemins’ sign.
=Two New Signs.=—Irregular, painless contractions of the uterus (Braxton
Hicks’ sign), and ballottement.
The contractions of Braxton Hicks now become more easily palpable.
Ballottement consists in the detection in the uterus of a movable solid
body surrounded by fluid. In a standing position, the fœtus rests in the
lower part of the uterus, just above the cervix. The woman stands with
one foot on a low stool, and two fingers of one hand are pushed into the
vagina until they touch the cervix, the other hand is placed on the
fundus. A smart upward blow by the internal hand is transmitted to the
fœtus, and it can be felt to leave the cervix, strike lightly the
tissues underneath the external hand, and return to the cervix. It is
simulated by so few things, and so rarely, that in practice it must be
regarded as a positive sign.
During the second half, the subjective symptoms are of minor importance
since unmistakable evidence is furnished by the physical signs. The
symptoms of this period are mostly discomforts. Increased intraabdominal
pressure brings on edema of the feet, cramps in the legs, varicose veins
of the legs and vulva, dyspnœa, and palpitations.
=Twenty-sixth Week.=—About the twenty-sixth week, or, at the end of the
sixth calendar month, the hypertrophy of the breasts, the presence of
secretion, and the marked pigmentation are unmistakable. The abdominal
protrusion is now clearly visible, and the fundus will be found at the
level of the upper border of the umbilicus.
Spontaneous fœtal movements appear and may be felt by the palpating
hand.
Auscultation reveals the uterine souffle and the fœtal heart sounds. The
heart sounds and the fœtal movements, when obtained by the observer, are
positive signs.
Uterine souffle is a soft, blowing murmur, synchronous with the mother’s
pulse. It is best heard at the lower parts of the lateral borders of the
uterus. It is due to the passage of blood through the greatly dilated
uterine arteries. It may be heard also in cases of fibroid tumors of the
uterus.
[Illustration: Fig. 27.—Abdominal enlargement at third, sixth, ninth,
and tenth months of pregnancy. (Williams.)]
[Illustration: Fig. 28.—Height of the uterus at various months of
pregnancy. (Bumm.)]
The fœtal heart sounds are the most anxiously sought for of all the
signs of pregnancy. They are conclusive. They not only determine the
diagnosis, but afford valuable information during labor, and nurse and
student should lose no opportunity of becoming familiar with them. The
heart tones can be heard as early as the twenty-sixth week, but they
become more and more distinct as pregnancy advances. They vary from 140
to 160 beats to the minute at the twenty-sixth week, and at term, from
120 to 140. When they rise above 160 or sink below 120, some danger
threatens the child. The fœtal heart tones have _no significance_ as an
indication of sex.
Funic souffle is the sound made by the passage of blood through the
umbilical cord when a loop accidentally lies under the tip of the
stethoscope. It is synchronous with the fœtal heart tones, but of no
great practical importance when the heart tones can be obtained.
Determination of the period to which pregnancy has advanced is sometimes
important. This can be approximated by a calculation of the time that
has elapsed since the last period, or from the date on which quickening
has occurred. Measurement of the height of the fundus and comparison
with such scales as Spiegelberg’s, may be carried out, but it is not
often required.
A method of estimation in gross, that is approximately correct, in many
cases depends on the observation of the steady growth of the womb.
Thus, the uterus rises out of the pelvis at the fourth month, and may be
found well above the symphysis pubis. At the fifth month the fundus is
midway between the symphysis and the umbilicus. At the sixth month it
reaches the umbilical level. At the eighth month it is a little more
than midway between the umbilicus and the ensiform cartilage, which it
attains in another month, the ninth. Then it usually sinks a little,
especially in primiparas during the last two or three weeks. This is
called _lightening_.