Exercise and Nutrition
How much exercise should a woman get during pregnancy? Many physicians strongly advise light exercise during pregnancy; it has been found to result in a greater sense of wellbeing, shorter labor, and fewer obstetric problems (Wang & Apgar, 1998). However, although participation in ongoing exercise throughout pregnancy can enhance birth weight, severe exercise can result in a low-birth-weight baby (Pivarnik, 1998). Most healthcare providers agree that a woman’s exercise routine should not exceed prepregnancy levels. If a woman exercised vigorously prior to her pregnancy, keeping up with a moderate amount of exercise during the pregnancy is fine.
Although it is true that pregnant women are “cardiovascularly challenged” early in pregnancy, it is a myth that too much exercise may cause a miscarriage or harm the developing fetus. Hundreds of pregnant women learned this prior to the legalization of abortion when they tried to exercise excessively or punch their abdomens in an unsuccessful attempt to dislodge the fertilized ovum. The implanted embryo is difficult to dislodge.
However, there are certain sports that should be avoided during pregnancy, such as water skiing, scuba diving, vigorous racquet sports, contact sports, and horseback riding, because these may cause injuries in both the mother and her fetus. Water exercise may be the best form of exercise for a pregnant woman because it causes fewer maternal and fetal heart rate changes and lower maternal blood pressure than land exercise (Katz, 1996). This is primarily due to a water-induced increase in circulating blood volume.
Physical stresses, such as prolonged standing, long work hours, and heavy lifting, can also affect a pregnancy. These stresses can reduce blood flow to the uterus, resulting in lower birth weights and prematurity (Clapp, 1996). It is also very important to drink lots of water during pregnancy because water is an essential nutrient and important for all bodily functions.
Question: I’ve heard women say that if the average baby weighs about 7 pounds, then they will gain no more than 10 pounds during pregnancy. Is that safe? How small a weight gain is considered healthy? What about anorexics and bulimics?
It is estimated that a pregnant woman of average size should gain between 31 and 40 pounds throughout a pregnancy. Underweight women should gain between 36 and 40 pounds, whereas overweight women should gain between 26 and 30 pounds (Bracero & Byrne, 1998). This accounts for the fetus, amniotic fluid, placenta, breasts, and muscle and fat increases. Gaining less than this is not healthy for either the developing baby or the mother—and may actually predispose a baby to obesity later in life (because fetuses learn to restrict calories in the womb, but when nutrition is readily available, overeating is likely). In addition, too little weight gain during pregnancy has also been found to be related to a higher blood pressure in offspring once they reach early childhood (P M. Clark et al., 1998). Anyone who has an eating disorder should consult with her healthcare provider before getting pregnant to determine an appropriate weight gain. If the nutritional requirements cannot be met, a woman should postpone pregnancy.
Nutritional requirements during pregnancy call for extra protein, iron, calcium, folic acid, and vitamin B6 (found in foods such as milk, yogurt, beef, legumes, and dried fruits). In addition, it is important for a woman to increase her caloric intake during pregnancy. Failure to follow these nutritional requirements may result in low-birth- weight children or even spontaneous abortion.
Research indicates that poor nutrition during pregnancy may also have long-term consequences for the infant’s risk of cardiovascular disease, hypertension, and diabetes (Godfrey et al., 1996). Fetuses who are forced to adapt to a limited supply of nutrients permanently “reprogram” their physiology and metabolism (Barker, 1997). In fact, in areas where food sources are limited, such as Sri Lanka or Bangladesh, the incidence of low-birth-weight deliveries ranges from 25% to 50% (compared to fewer than 7% in the United States; Gopalan, 1996). In addition, the majority of children in these areas suffer from mild to moderate forms of growth retardation.
During the second trimester, a woman is advised to increase her caloric intake by 300 calories per day, and protein requirements increase. For vegetarians, it is necessary to increase consumption of vegetables, whole grains, nuts, seeds, and also include a protein supplement to help ensure adequate protein intake. An increase in calcium is also needed to help with bone calcification of the growing fetus. Because a woman’s blood volume increases as much as 50% during pregnancy, iron may be diluted in the blood; thus many pregnant women are advised to take prenatal vitamins, which include iron supplements.
Drugs and Alcohol
There are several substances that physicians recommend to avoid during pregnancy, including caffeine, nicotine, alcohol, marijuana, and other drugs (the accompanying Human Sexuality in a Diverse World, “Avoid the Sun?,” describes activities that women in other cultures are told to avoid). All of these substances can cross the placenta, enter into the developing fetus’s bloodstream, and cause physical or mental deficiencies. Fetal alcohol syndrome (FAS), a condition associated with alcohol intake, occurs when a woman drinks heavily during pregnancy, producing an infant with irreversible physical and mental disabilities. Even women who drink very little put their developing babies at risk. Presently, experts agree that there is no safe level of alcohol use during pregnancy.
It is estimated that 11% of U. S. women smoke cigarettes throughout their pregnancy (Centers for Disease Control and Prevention, 2004c). Smoking during pregnancy
Human Sexuality in a Diverse World