Topic Resources
Pregnancy causes many changes in a woman’s body. Most of them disappear after delivery. These changes cause some symptoms, which are normal. However, certain disorders, such as gestational diabetes, can develop during pregnancy, and some symptoms may indicate such a disorder.
Symptoms that should be immediately reported to a doctor if they occur during pregnancy include the following:
-
Persistent or unusual headaches
-
Persistent nausea and vomiting
-
Light-headedness
-
Disturbances of eyesight
-
Contractions
-
Leakage of amniotic fluid (described as "the water breaks")
-
Swelling of the hands or feet
-
Decreased urine production
-
Any illness or infection
-
Tremor (shaking of the hands, feet, or both)
-
Seizures
-
Rapid heart rate
-
Decreased movement of the fetus
If labor was quick in previous pregnancies, women should notify their doctor as soon as they have any indication that labor is starting.
General health
Fatigue is common, especially in the first 12 weeks and again in late pregnancy. The woman may need to get more rest than usual.
Reproductive tract
By 12 weeks of pregnancy, the enlarging uterus may cause the
woman’s abdomen to protrude slightly. The uterus continues to enlarge
throughout pregnancy. The enlarging uterus extends to the level of the
navel by 20 weeks and to the lower edge of the rib cage by 36 weeks.
The amount of normal vaginal discharge, which is clear or
whitish, commonly increases. This increase is usually normal. However,
if the discharge has an unusual color or smell or is accompanied by
vaginal itching and burning, a woman should see her doctor. Such
symptoms may indicate a vaginal infection. Some vaginal infections, such
as trichomoniasis (a protozoan infection) and candidiasis (a yeast infection), are common during pregnancy and can be treated.
Breasts
The breasts tend to enlarge because hormones (mainly estrogen)
are preparing the breasts for milk production. The glands that produce
milk gradually increase in number and become able to produce milk. The
breasts may feel firm and tender. Wearing a bra that fits properly and
provides support may help.
During the last weeks of pregnancy, the breasts may produce a
thin, yellowish or milky discharge (colostrum). Colostrum is also
produced during the first few days after delivery, before breast milk is
produced. This fluid, which is rich in minerals and antibodies, is the
breastfed baby's first food.
Heart and blood flow
During pregnancy, the woman’s heart must work harder because as
the fetus grows, the heart must pump more blood to the uterus. By the
end of pregnancy, the uterus is receiving one fifth of the woman’s
prepregnancy blood supply. During pregnancy, the amount of blood pumped
by the heart (cardiac output) increases by 30 to 50%. As cardiac output
increases, the heart rate at rest speeds up from a normal prepregnancy
rate of about 70 beats per minute to 80 or 90 beats per minute. During
exercise, cardiac output and heart rate increase more when a woman is
pregnant than when she is not.
At about 30 weeks of pregnancy, cardiac output decreases slightly. Then during labor, it increases by an additional 30%. After delivery, cardiac output decreases rapidly at first, then more slowly. It returns to the prepregnancy level about 6 weeks after delivery.
At about 30 weeks of pregnancy, cardiac output decreases slightly. Then during labor, it increases by an additional 30%. After delivery, cardiac output decreases rapidly at first, then more slowly. It returns to the prepregnancy level about 6 weeks after delivery.
Certain heart murmurs and irregularities in heart rhythm may appear because the heart is working harder. Sometimes a pregnant woman may feel these irregularities. Such changes are normal during pregnancy. However, other abnormal heart sounds and rhythms (for example, diastolic murmurs and a rapid, irregular heart rate), which occur more often in pregnant women, may require treatment.
Blood pressure usually decreases during the 2nd trimester but may return to a normal prepregnancy level in the 3rd trimester.
The volume of blood increases by almost 50% during pregnancy. The
amount of fluid in the blood increases more than the number of red
blood cells (which carry oxygen). Thus, even though there are more red
blood cells, blood tests indicate mild anemia, which is normal. For
reasons not clearly understood, the number of white blood cells (which
fight infection) increases slightly during pregnancy and increases
markedly during labor and the first few days after delivery.
The enlarging uterus interferes with the return of blood from the legs and the pelvic area to the heart.
As a result, swelling (edema) is common, especially in the legs. Varicose veins commonly develop in the legs and in the area around the vaginal opening (vulva). They sometimes cause discomfort.
Clothing that is loose around the waist and legs is more comfortable and does not restrict blood flow. Some measures not only ease the discomfort but may also reduce leg swelling and make varicose veins more likely to disappear after delivery:
-
Wearing elastic support hose
-
Resting frequently with the legs elevated
-
Lying on the left side
Urinary tract
Like the heart, the kidneys work harder throughout pregnancy.
They filter the increasing volume of blood. The volume of blood filtered
by the kidneys reaches a maximum between 16 and 24 weeks and remains at
the maximum until just before the baby is due. Then, pressure from the
enlarging uterus may slightly decrease the blood supply to the kidneys.
Activity of the kidneys normally increases when a person lies
down and decreases when a person stands. This difference is amplified
during pregnancy—one reason a pregnant woman needs to urinate frequently
while trying to sleep. Late in pregnancy, lying on the side,
particularly the left side, increases kidney activity more than lying on
the back. Lying on the left side relieves the pressure that the
enlarged uterus puts on the main vein that carries blood from the legs.
As a result, blood flow improves and kidney activity increases.
The uterus presses on the bladder, reducing its size so that it
fills with urine more quickly than usual. This pressure also makes a
pregnant woman need to urinate more often and more urgently.
Respiratory tract
The high level of progesterone,
a hormone produced continuously during pregnancy, signals the brain to
lower the level of carbon dioxide in the blood. As a result, a pregnant
woman breathes slightly faster and more deeply to exhale more carbon
dioxide and keep the carbon dioxide level low. She may breathe faster
also because the enlarging uterus limits how much the lungs can expand
when she breathes in. The circumference of the woman’s chest enlarges
slightly.
Virtually every pregnant woman becomes somewhat more out of
breath when she exerts herself, especially toward the end of pregnancy.
During exercise, the breathing rate increases more when a woman is
pregnant than when she is not.
Because more blood is being pumped, the lining of the airways
receives more blood and swells somewhat, narrowing the airways. As a
result, the nose occasionally feels stuffy, and the eustachian tubes
(which connect the middle ear and back of the nose) may become blocked.
These effects can slightly change the tone and quality of the woman’s
voice.
Digestive tract
Nausea and vomiting, particularly in the mornings (morning sickness), are common. They may be caused by the high levels of estrogen and human chorionic gonadotropin, two hormones that help maintain the pregnancy.
Nausea and vomiting may be relieved by changing the diet or patterns of eating—for example, by doing the following:
-
Drinking and eating small portions frequently
-
Eating before getting hungry
-
Eating bland foods (such as bouillon, consommé, rice, and pasta)
-
Eating plain soda crackers and sipping a carbonated drink
-
Keeping crackers by the bed and eating one or two before getting up to relieve morning sickness
No drugs specifically designed to treat morning sickness are
currently available. Sometimes nausea and vomiting are so intense or
persistent that dehydration, weight loss, or other problems develop—a
disorder called hyperemesis gravidarum.
Women with this disorder may need to be treated with drugs that relieve
nausea (antiemetic drugs) or to be hospitalized temporarily and given
fluids intravenously.
Heartburn and belching are common, possibly because food remains
in the stomach longer and because the ringlike muscle (sphincter) at the
lower end of the esophagus tends to relax, allowing the stomach’s
contents to flow backward into the esophagus. Several measures can help
relieve heartburn:
-
Eating smaller meals
-
Not bending or lying flat for several hours after eating
-
Avoiding caffeine, tobacco, alcohol, and aspirin and related drugs (salicylates)
-
Taking liquid antacids, but not antacids that contain sodium bicarbonate because they contain so much salt (sodium)
Heartburn during the night can be relieved by the following:
-
Not eating for several hours before going to bed
-
Raising the head of the bed or using pillows to raise the head and shoulders
The stomach produces less acid during pregnancy. Consequently, stomach ulcers rarely develop during pregnancy, and those that already exist often start to heal.
As pregnancy progresses, pressure from the enlarging uterus on
the rectum and the lower part of the intestine may cause constipation.
Constipation may be worsened because the high level of progesterone
during pregnancy slows the automatic waves of muscular contractions in
the intestine, which normally move food along. Eating a high-fiber diet,
drinking plenty of fluids, and exercising regularly can help prevent
constipation.
Hemorrhoids, a common problem, may result from pressure of the
enlarging uterus or from constipation. Stool softeners, an anesthetic
gel, or warm soaks can be used if hemorrhoids hurt.
Pica, a craving for strange foods or nonfoods (such as starch or clay), may develop.
Occasionally, pregnant women, usually those who also have morning
sickness, have excess saliva. This symptom may be distressing but is
harmless.
Skin
Mask of pregnancy (melasma) is a blotchy, brownish pigment that
may appear on the skin of the forehead and cheeks. The skin surrounding
the nipples (areolae) may also darken. A dark line commonly appears down
the middle of the abdomen. These changes may occur because the placenta
produces a hormone that stimulates melanocytes, the cells that make a
dark brown skin pigment (melanin).
Pink stretch marks sometimes appear on the abdomen. This change
probably results from rapid growth of the uterus and an increase in
levels of adrenal hormones.
Melasma
DR P. MARAZZI/SCIENCE PHOTO LIBRARY
Small blood vessels may form a red spiderlike pattern on the skin, usually above the waist. These formations are called spider angiomas. Thin-walled, dilated capillaries may become visible, especially in the lower legs.
Spider Angiomas
Image provided by Thomas Habif, MD.
Urticarial Papules and Plaques of Pregnancy
© Springer Science+Business Media
Pemphigoid Gestationis
© Springer Science+Business Media
Two intensely itchy rashes occur only during pregnancy:
-
Pruritic urticarial papules and plaques of pregnancy (urticaria of pregnancy) typically appears during the last 2 to 3 weeks of pregnancy but may appear any time after the 24th week. The cause is unknown.
-
Pemphigoid (herpes) gestationis can appear any time after the 12th week of pregnancy or immediately after delivery. The cause is thought to be abnormal antibodies that attack the body’s own tissues—an autoimmune reaction.
Hormones
Pregnancy affects virtually all hormones in the body, mostly
because of the effects of hormones produced by the placenta. For
example, the placenta produces a hormone that stimulates the woman’s
thyroid gland to become more active and produce larger amounts of
thyroid hormones. When the thyroid gland becomes more active, the heart
may beat faster, causing the woman to become aware of her heartbeat
(have palpitations). Perspiration may increase, mood swings may occur,
and the thyroid gland may enlarge. However, the disorder hyperthyroidism, in which the thyroid gland malfunctions and is overactive, develops in fewer than 0.1% of pregnancies.
Levels of estrogen and progesterone
increase early during pregnancy because human chorionic gonadotropin,
the main hormone the placenta produces, stimulates the ovaries to
continuously produce them. After 9 to 10 weeks of pregnancy, the
placenta itself produces large amounts of estrogen and progesterone. Estrogen and progesterone help maintain the pregnancy.
The placenta stimulates the adrenal glands to produce more aldosterone and cortisol (which help regulate how much fluid the kidneys excrete). As a result, more fluids are retained.
During pregnancy, changes in hormone levels affect how the body
handles sugar. Early in pregnancy, the sugar (glucose) level in the
blood may decrease slightly. But in the last half of pregnancy, the
level may increase. More insulin
(a hormone that controls the sugar level in the blood) is needed during
pregnancy. Consequently, diabetes, if already present, may worsen
during pregnancy. Diabetes can also begin during pregnancy. This
disorder is called gestational diabetes.
Joints and muscles
The joints and ligaments (fibrous cords and cartilage that
connect bones) in the woman’s pelvis loosen and become more flexible.
This change helps make room for the enlarging uterus and prepare the
woman for delivery of the baby. As a result, the woman’s posture changes
somewhat.
Backache in varying degrees is common because the spine curves
more to balance the weight of the enlarging uterus. Avoiding heavy
lifting, bending the knees (not the waist) to pick things up, and
maintaining good posture can help. Wearing flat shoes with good support
or a lightweight maternity girdle may reduce strain on the back.
Posts
0 Comments