The results of a large study show that obesity and diabetes are independent risk factors for a number of adverse pregnancy outcomes, such as cesarean delivery and having an infant with a low birth weight. The magnitude of the effect, however, varies by racial and ethnic group.
As reported in the American Journal of Public Health, Dr. Terry J. Rosenberg, from the Medical Health and Research Association of New York City, and colleagues analyzed information from 329,988 births to determine the impact of obesity and diabetes on pregnancy outcomes and the effect, if any, of race or ethnic group.
The researchers found that all women with gestational or chronic diabetes had an increased risk of cesarean delivery. The increased risk ranged from 23 percent for whites with gestational diabetes an almost threefold increased risk for Hispanics with chronic diabetes.
Similarly, diabetes was tied to elevated risks of preterm births in all of the groups. In this case, the increased risk ranged from 20 percent for whites with gestational diabetes to more than threefold for Hispanics with chronic diabetes.
The effect of diabetes on low birthweight was less clear. Chronic diabetes was associated with an increased risk of low infant birthweight in all groups. In contrast, gestational diabetes had no significant effect on this outcome in whites or Asians, and was tied to a significantly reduced risk in blacks and Hispanics.
For all groups, prepregnancy weight higher than 149 pounds was tied to increased risk of preeclampsia. Also known as toxicemia of pregnancy, preeclampsia is marked by high blood pressure, fluid retention and protein in the urine. If untreated, this condition may progress to eclampsia, a life-threatening complication.
Increased body weight also raised the risk of cesarean delivery, but was associated with a reduced risk of low infant birthweight.
“Although careful monitoring of diabetes during pregnancy can improve pregnancy outcomes for diabetic women,” the authors conclude, “the longer-term public health approach should be to prevent type 2 diabetes and gestational diabetes by controlling women’s weight over their lifetimes.”
SOURCE: American Journal of Public Health, September 2005.