Exercise and Pregnancy "How much, and how intensively, nurse, should I exercise over the course of my pregnancy?' A seemingly simple question -- and one a gynecological or obstetrical nurse must be prepared to answer, given that many newly pregnant women may feel more comfortable directing such queries to a nursing staff health care provider, rather than a physician. This may be particularly the case if the attending physician is male, and the woman has concerns germane to the 'female' experience of pregnancy and exercise, such as weight control or temporary pregnancy-specific problems related to exercise such as bladder or back pain or incontinence. But as nursing strives to teach and treat the whole individual undergoing a pregnancy, all nurses must be prepared to answer such crucial questions as to how much, when, and how a pregnant woman should exercise.

Article 1: 1998 Overview from the American Family Physician

As Thomas W. Wang and Barbara S. Apagar (1998) point out, the benefits of regular exercise for nonpregnant women are generally acknowledged and "indeed, an exercise regimen has become an integral part of daily life for many women." (Wang & Apagar, 1998, p.1) However, theoretic as well as practical concerns have often arisen regarding the effects of exercise on pregnant women, questions that Wang and Apagar strive to answer in their 1998 article "Exercise during Pregnancy" from the American Family Physician. Despite the common images of celebrities exercising well into their pregnancies, and the commonness of the condition itself, the authors note that "objective data on the impact of exercise on the mother, the fetus and the course of pregnancy" was limited during the authorship of their article, "and results of the few studies in humans" regarding exercise could be described as "often equivocal or contradictory," causing medical practitoners to err on the side of conservativism and to limit women's exercise, thinking it better to be safe than sorry, given the terminal nature of the condition and its potential long-lasting impact to endanger the patient's future progeny. (Wang & Apagar, 1998, p.1)

"Although various exercise guidelines are available, they are usually conservative and are frequently based on controversial opinions," opinions-based either in the biases of exercise zealots, or conversely physicans fearing lawsuits. (Wang & Apagar, 1998, p.1) For example, clinical studies, women who exercise during pregnancy do not show significant differences in weight during the first and second trimesters. However, some evidence suggests that continuous exercise in the second and third trimesters is associated with decreased maternal and fetal weight gain in the third trimester, but of statistically insignificant, according to the authors. Also, the studies surveyed in this overview article did not find any evidence of an increase in preterm labor, premature rupture of the membranes or added fetal distress in any of the comparative studies of exercising and relatively inactive pregnant women. The one conclusive factor was that exercise migh have a favorable effect on the subjective experience of discomfort during pregnancy. (Wang & Apagar, 1988, p.2)

However, also clearly established is that weight-bearing exercise such as running or jogging becomes a greater concern when vertical impact forces, which are usually twice an individual's body weight, are further increased during pregnancy. Sudden movements may exacerbate these mechanical difficulties and increase the potential for injury of the pregnant woman's body. Furthermore, most women "report greater discomfort with exercise in the later stages of pregnancy. (Wang & Apagar, 1998, p.1) During pregnancy, hormonal changes are thought to induce a greater laxity in joints and increases in joint laxity may lead to a higher risk of strains or sprains for the woman. From the point-of-view of the athletic coach of the pregnant women, and confirmed in a study of well-trained runners, there is "a progressive decline in all aspects of performance during pregnancy." (Wang & Apagar, 1998, p.1) But from the point-of-view of maternal health, the authors of the survey article conclude, although data remains rather sparse, "there appears to be no reason why women who are in good health should not be permitted to engage in exercise while pregnant. However, women with medical or obstetric complications should be encouraged to avoid vigorous physical activity. Given the current lack of data, a conservative approach is warranted when doubt exists." (Wang & Apagar, p.2)

Article 2: 2002 Study on Pregnant Women in the Military from the American Family Physician

A 2002 article from the same journal, American Family Physician, strikes a more cautious note upon the subject of pregnancy and exercise. It specifically targets the issue of low birth weight, one of the potential concerns of the 1998 survey that was, to some...

Anne Walling however, notes that "even though more women are exercising during pregnancy, and many more pregnant women are involved in strenuous activity because they work outside the home up until delivery, the effect of exercise on birth weight and pregnancy outcome" are unclear and must be studied further, even in healthy women. (Walling, 2002, p.1) Walling notes that most reviews have been unable to demonstrate risks or, in her view, benefits to the mother or fetus. "Studies have given conflicting results on outcomes such as birth weight, maternal weight gain, rate of operative delivery, and other complications. Interpretation of studies is difficult because of differences in methodology, the populations studied, and confounding variables in the pregnant women studied. Magann and colleagues studied women enlisted in the military to evaluate the effect of exercise on pregnancy outcomes." (Walling, 2002, p.1)
The authors of the controlled study cited in her article did not differ significantly in demographic characteristics or in significant variables such as smoking, stress, social support, or previous illnesses, but mothers who exercised heavily were older and had higher incomes than women in other groups, and the balance of the study was not able to counteract this bias. Overall, the groups of moderately exercising, heavily exercising, and nonexercising women were all similar in rates of pregnancy loss, neonatal death, pregnancy-induced hypertension or diabetes, anemia, and antenatal hospital admission. "Women who exercised reported more acute upper respiratory problems (colds and influenza) but fewer umbilical cord abnormalities than less active women. Exercising women were significantly more likely to require induction of labor and augmentation of labor with oxytocin, and to have longer first stages than nonexercisers. The women who exercised heavily had infants of lower birth weight than sedentary women, and this rate remained significant after controlling for other significant variables. Moderate to heavy exercise was associated with infants averaging 86.5 g less than those of nonexercising women." (Walling, 2002, p.1)

Thus, Walling concluded that the smaller infants of exercising mothers had restricted growth limited to a restriction of neonatal fat mass. However, they appeared to suffer no adverse consequences. In fact, Walling added that the slightly lower birth weight of the infants might even suggest that this restriction may have preventive value in reducing the risk of obesity later in life, although this is admittedly a purely speculative notion. Exercise thus did not appear affect antenatal, intrapartum, or postpartum complications of pregnancy in healthy low-risk mothers, but it does appear to affect birth weight in intensively exercising mothers, who were generally older than other mothers in the study.

Article 3: 2004 Study on Gestational Diabetes and Pregnant Women and Exercise from the American Family Physician

All well and good, one might say, but what of women with pregnancies which are not complication free? In fact, 2004 article by Karl Miller states that not only can exercise programs can benefit pregnant patients with gestational diabetes, but specifically "aerobic exercise has been shown to decrease insulin needs in patients with gestational diabetes." Carbohydrate intolerance that develops or is first recognized during pregnancy is labeled gestational diabetes mellitus. This form of diabetes can significantly affect the mother and fetus during pregnancy and increases the risk of adverse pregnancy-related outcomes, thus it is vital to control during its early stages. (Miller, 2004, p.1)

"Women who are diagnosed with gestational diabetes have a significant risk of recurrent gestational diabetes in subsequent pregnancies, and a significant number develop type 2 diabetes as they age. The current treatment strategy is to control blood glucose levels through diet and, when needed, insulin therapy. Although insulin therapy has a positive effect on pregnancy outcomes in these patients," it does not address the main issue of insulin resistance so critical to the issue of diabetes, unlike exercise which does aid in improving insulin resistance. (Miller, 2004, p.1)

Miller states in his article that the authors of the study concluded that resistance exercise training may help to avoid the use of insulin therapy in overweight women with gestational diabetes mellitus. In addition, exercise can reduce the need for insulin and prolong the latency period to insulin use in these patients. The exercise would not be heavy, as it was "Participants were assigned randomly to diet alone or diet plus resistance exercise.

Summary of Three Articles

The first survey article suggests that exercise during pregnancy is not contraindicated during a normal, healthy gestation, with the possible risk of slightly lower birth rate. The second article…