Prepregnancy body mass index and gestational age-dependent changes in lipid levels during pregnancy.

OBJECTIVE

To examine the effect of maternal prepregnancy overweight and obesity on gestational age-dependent variation in lipid levels during pregnancy.

METHODS

Women between 6 and 10 weeks of gestation who carry a single, live intrauterine pregnancy were eligible to participate in a prospective pregnancy study (N=142). The exposure, maternal prepregnancy body mass index (BMI), was classified as: normal weight (BMI 18.5-26.0 kg/m) and overweight or obese (BMI over 26.0 kg/m). Our outcomes of interest, total cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol were measured at 6-10, 10-14, 16-20, 22-26, and 32-36 weeks of gestation. Mixed linear models were used to examine how the trajectory of lipid levels during pregnancy differs between overweight or obese and normal-weight women.

RESULTS

Levels of total cholesterol, triglycerides, LDL cholesterol, and HDL choloesterol increased over the prenatal period. The rate of change in LDL cholesterol (P<.001) and total cholesterol (P=.01) levels was lower for overweight or obese women than for normal-weight women in late-second and early-third trimester. As a result, overweight or obese women had significantly lower total cholesterol and LDL cholesterol levels than their normal-weight counterparts between 32-36 weeks of gestation.

CONCLUSION

Overweight and obese women have different lipid profiles during pregnancy than their normal-weight peers. This difference may be the result of metabolic dysregulation associated with maternal overweight and obesity that mediates the increased risk of adverse outcomes found in these women.

LEVEL OF EVIDENCE: II.