Water retention is a common complaint throughout pregnancy
Extra fluid also opens the pelvic tissues to enable the birth canal to expand so the baby can be delivered.
During pregnancy, the uterus grows from an organ that ordinarily weighs approximately 70 g (between 2 and 3 ounces) with an interior space of 1 ml (enough to accommodate a few drops of fluid) to an organ that weighs more than 1000 g (approximately 2 pounds) with an interior space of 20 liters (5 gallons). The additional fluid needed to supply the uterus and the growing fetus commonly causes edema, or swelling, first in the feet and then in the hands and throughout the body, but getting rid of edema demands measures particular to pregnancy.
During pregnancy, the reaction of the kidneys to increasing sodium levels is the quite unlike their response whbiobioen the woman is not pregnant. Normally, when sodium levels go up, the kidneys maintain a steady concentration by retaining water. When sodium levels go down, the kidneys maintain that same narrow range of sodium concentration in the blood by excreting water. Keeping sodium concentrations steady is important to a host of body processes, especially the ability of nerves to transmit electrical messages.
In pregnancy, however, there is a very different pattern. Even if the sodium concentrations of the bloodstream go down, the amount of fluid retained by kidneys still goes up. The body of a pregnant woman diverts fluid from the mother to the growing child. It diverts sodium to the fetus. This results in underfilling most the arteries in the woman's body to allow for overfilling the arteries serving the uterus.1 In pregnant women, there can be swelling even if salty foods are avoided and sodium is removed by diuretics.
Swelling at Different Stages of Pregnancy
In the first month after conception, bloating and edema are not yet due to the developing baby. It can be difficult for a woman to distinguish the difference between premenstrual swelling and the additional fluid her body accumulates to cushion the uterus and normalize blood pressure. By the third month, however, up to 50 per cent of all pregnant women experience swelling in the hands and feet. Extra pounds before pregnancy almost cause extra swelling during pregnancy. Women who are obese have more difficulty with fluid retention.
Although in most cases pregnancy-related swelling is only annoying, edema related to a condition called preeclampsia can be light threatening. In this condition, occurring in approximately 1 in 400 pregnancies among women who receive prenatal care but 1 in 20 pregnancies among women who do not,2 the fluids in the body increase but they are not diverted to the growing fetus. Preeclampsia is the third most frequent cause of death in pregnant women, after blood loss and embolism.
Very sudden and severe swelling is a medical emergency, especially if it is accompanied by blurred vision, headache, painful urination, no urination for more than 12 hours, bleeding, cramping, abdominal pain, or a significant weight gain not brought on by overeating. Swelling accompanying high blood pressure or gestational diabetes likewise require close medical attention. These conditions cannot be treated by diuretics alone, but diuretics are not the first line of successful treatment even for more benign manifestations of edema in pregnancy.3
Chemical vs. Natural Diuretics During Pregnancy
The cheapest and most frequently prescribed diuretics, such as the old standby hydrochlorothiazide (HCTZ), work by causing the kidneys to increase the excretion of sodium. Adequate levels of sodium, however, are essential to the fetus, and getting rid of sodium does not address the underlying problem. Pregnant women are far more likely to get relief by doing things that even out the circulation of fluid rather than trying to get rid of it. Expectant mothers should:
- Avoid clothes that constrict the wrists or ankles.
- Minimize time outdoors when temperatures are over 75-85 0F (approximately 25-30 0C).
- Rest with feet elevated, but do not do handwork with feet elevated, since this can induce swelling of the carpal tunnel.
- Use ice packs or cold compresses on swollen areas.
- Wear comfortable shoes, never high heels.
- Wear support tights or stockings.
A woman's body increases blood pressure in the lower extremities, that is, the feet and ankles, to keep blood pressure more nearly normal closer to major organs. The feet and ankles are usually the first to swell and the first to need support.
It also helps to avoid excessive consumption of caffeine and to ensure adequate consumption of potassium-rich fruits and vegetables. Getting too much caffeine from coffee, tea, and soft drinks will not, as often reported, lead to dehydration, but it will induce frequent urination, especially at night.4
Water aerobics are also recommended as a way to relieve swelling during pregnancy, but exercise is not essential. A clinical trial at the Sacred Heart Medical Center in Eugene, Oregon found that simply taking a soak in warm water was as effective as exercise in water for relieving swelling of the feet, ankles, and legs.5
Herbal Diuretics During Pregnancy
The best-known herbal remedy for swelling in pregnancy is dandelion leaf. Eaten in salads or dried and brewed into a tea, dandelion is an excellent source of calcium, iron, and beta-carotene with phytochemicals that encourage the elimination of excess fluid.6 Oats and oats straw used in teas are a rich source of calcium and magnesium. They relieve muscle pain and calm nerves. Both dandelion and oats are safe for pregnant women and nursing mothers.
Ginger is not a diuretic, but it helps with many of the symptoms of pregnancy. Increased production of estrogen makes the linings of the digestive tract more sensitive to even the slightest signs of contamination in food. Ginger supplements and ginger teas help maintain normal concentrations of electrolytes and normal (for pregnancy) fluid balance by stopping nausea and vomiting.7
Women who suffer edema during pregnancy, ironically, should take care to maintain adequate hydration. Dark yellow or brownish urine is a sign of inadequate water intake. Drinking water is the best way to remain hydrated and essential to good health before, during, and after the birth of the child.