Body weight gain and serum leptin levels of non-overweight and overweight/obese pregnant women

BACKGROUND: Our objective was to evaluate changes in serum leptin levels during pregnancy in overweight/obese and non-obese women and to assess total and percent weight gain during pregnancy as possible factors that influence leptin levels. MATERIAL AND METHODS: In a prospective study of 42 low-risk pregnant women receiving prenatal care, we assessed serum leptin levels at gestational weeks 9-12, 25-28, and 34-37. Based on their pre-pregnancy body mass indices (BMIs), the cohort was divided into: non-overweight (BMI <25 kg/m(2)) and overweight/obese (BMI ≥ 25 kg/m(2)) subjects. RESULTS: We found a progressive increase in maternal weight gain during pregnancy in both groups. There was also a progressive increase in leptin levels in the 2 strata; however, the increase was significantly higher in the non-overweight patient group. We found that non-overweight pregnant women had a noticeably larger total weight gain. When analyzing the percent weight gain during pregnancy compared to the pre-pregnancy weight, the non-overweight group had a significantly greater percent weight gain than the overweight/obese group. CONCLUSIONS: Our results suggest that the greater increase in leptin levels in non-overweight pregnant women can be explained by the higher percent weight gain in this group compared to overweight/obese women. These findings suggest that controlling the percent weight gain may be an important preventive measure when controlling leptin levels during pregnancy and subsequent medical complications.