Objectives: To study the correlation between amniotic fluid leptin levels and maternal serum leptin levels during the early second trimester, and to determine whether the ratios of amniotic fluid leptin levels to maternal serum leptin levels are elevated in pregnant women who subsequently develop preeclampsia.
Study design: Samples from 120 pregnant women were included in this prospective study, of which 20 were from pregnant women who subsequently developed preeclampsia and 100 were from normal pregnant women. Both the amniotic fluid and the maternal serum leptin levels were ascertained by radioimmunoassay (RIA).
Results: A strong correlation between amniotic fluid leptin levels and maternal serum leptin levels was observed in both preeclamptic and normal pregnant women. In addition, the ratios of amniotic fluid leptin levels to maternal serum leptin levels were positively correlated to amniotic fluid leptin levels, but negatively correlated to maternal serum leptin levels. Furthermore, the ratios of amniotic fluid leptin levels to maternal serum leptin levels in preeclamptic women were significantly higher than those in normal pregnant women.
Conclusions: Amniotic fluid leptin levels correlated with maternal serum leptin levels during the early second trimester. The ratios of amniotic fluid leptin levels to maternal serum leptin levels were elevated in preeclamptic women. However, the maternal serum leptin levels themselves showed no such elevation. Therefore, this elevated ratio may be a marker at the early stage of pregnancy in preeclamptic women.