Does physical activity during pregnancy reduce the risk of gestational diabetes among previously inactive women?
GROUND: Gestational diabetes affects approximately 7 percent of all pregnancies in the United States; its prevalence may have increased among all ethnic groups since the early 1990 s. Our study examined whether physical activity during pregnancy reduced the risk of gestational diabetes among women who were physically inactive before pregnancy. METHODS: We used data from the 1988 National Maternal and Infant Health Survey (NMIHS), a nationally representative sample of mothers with live births. The NMIHS obtained mothers’ gestational diabetes diagnoses from care providers and mothers reported their physical activity before and during pregnancy, including the number of months with physical activity and types of physical activity. We developed a physical activity index, the product of the number of months with physical activity, and average metabolic equivalents for specific activities. The analysis included 4,813 women who reported being physically inactive before pregnancy, with singleto
