[Examining consecutively serum leptin levels in normal pregnant and pregnancy-induced hypertension women].

OBJECTIVE

To detect successsively serum leptin levels in normal, pregnancy-induced hypertension (PIH) pregnant women.

METHODS

Levels of serum leptin were measured in the 16-20, 24-28, 32-36 weeks of gestation, at the delivery time in 50 healthy, 14 PIH pregnant women and their newborns and in 40 healthy non-pregnant women by Immuno-radioassay method. Serum leptin levels were correlated with body weight, body mass index (BMI), blood pressure and placental weight.

RESULTS

(1) The serum leptin levels were increased gradually during the normal (14.1 +/- 2.2)-(25.4 +/- 2.7) micro g/L and the PIH pregnancy [(13.4 +/- 3.0)-(21.4 +/- 3.7)] micro g/L, especially in the PIH women. It was found that leptin concentrations rose markedly from 28 to 36 weeks of gestation, but increased slightly before the 28 weeks of gestation and after the 36 weeks of gestation in normals, and in contrast to the normal pregnancy, consistently higher until to the delivery time in the PIH. (2) The positive correlations were significant between the levels of serum leptin with their body weight and BMI in the normal pregnant and non-pregnant women (r = 0.478-0.639, P < 0.05 or P < 0.01), but not significant in the PIH pregnant (r = 0.035-0.379, P > 0.05). (3) The positive correlations were significant between the serum leptin concentrations and the systolic blood pressure, diastolic blood pressure and mean artery pressure in the PIH women after 20 weeks of gestation (r = 0.639-0.852, P < 0.05), but not significant in the normal pregnant, the PIH before 20 weeks of gestation and the non-pregnant women (r = 0.113-0.498, P > 0.05). (4) Before the delivery time, the positive correlation between the serum leptin concentrations of the pregnant women and that of the newborns was not significant, and also not significant between the puerperas' serum leptin levels and the placental weight in the normal pregnant (r = 0.132, 0.097, P > 0.05). But it was interesting that significant positive correlation was found between the puerperas' serum leptin concentrations and the cord serum leptin levels (r = 0.792, P < 0.01) and significant negative correlation was detected between the puerperas' serum leptin levels and the placental weight in the PIH women (r = -0.819, P < 0.01). (5) The leptin levels of cord blood were positively correlated with the body weight and BMI of newborns in both of the normal and PIH pregnancy (r = 0.520-0.655, P < 0.05 or P < 0.01).

CONCLUSION

The characteristic change of serum leptin levels and correlations between the serum leptin concentrations and the related pregnant signs was different in normal and PIH pregnancy.