[Serum leptin levels during pregnancy]

To study the serum leptin levels in Chinese pregnant women, and to discuss the relationship between leptin level and pregnancy.

Serum leptin concentrations of 251 pregnant women (13.6 to 30.9 gestational weeks) were measured with radioimmunoassay, and 35 age and body mass index (BMI) matched non-pregnant women were selected as control. Serum leptin concentrations were compared between pregnant and control women, correlations between leptin concentrations and gestational age, weight, BMI, blood pressure and other parameters were analyzed.

In these pregnant women, aged (28.5 +/- 3.9) years, BMI (23.6 +/- 2.8) kg/m2, serum leptin concentrations were (15.1 +/- 7.4) micrograms/L; while in control women, aged (27.4 +/- 3.8) years, BMI (22.6 +/- 2.5) kg/m2, serum leptin concentrations were (9.1 +/- 4.9) micrograms/L. The mean age and BMI are comparable between 2 groups. Serum leptin concentrations in pregnant women were much higher than those in control women (P < 0.001). Within the pregnant women, serum leptin concentrations were significantly correlated to body weight(r = 0.529), BMI (r = 0.551,), waist circumference (r = 0.564), height of uterus bottom (r = 0.151), systolic blood pressure (r = 0.134) and diastolic blood pressure (r = 0.251). During pregnancy, serum leptin concentrations rose along with the gestational age, although no statistical difference was revealed up to 30th gestational week.

Leptin is a hormone intimately related to the pregnancy, its concentrations are much higher during pregnancy than those of non-pregnant women with matched age and BMI. Like in non-pregnant women, leptin levels are significantly correlated to body weight and BMI, and also correlated to blood pressure, the correlation between leptin and diastolic blood pressure is more evident, indicating that serum leptin may serve as a marker for detecting and monitoring pregnancy complications.