Serum Leptin Levels in Preeclamptic Pregnant Women: Relationship to Thyroid-Stimulating Hormone, Body Mass Index, and Proteinuria

ABSTRACT

The objective of this study was to evaluate the change in maternal serum leptin levels in preeclampsia and to study the relationship between maternal serum leptin and thyroid-stimulating hormone (TSH), body mass index (BMI), newborn weight, and proteinuria. Eighty-five pregnant women were included in this prospective study, of whom 50 were preeclamptic and 35 were normotensive. Maternal serum leptin levels were measured by the radioimmunoassay technique and TSH levels were measured by the electrochemiluminescence immunoassay method. The maternal serum leptin levels of preeclamptic and normotensive pregnant women were compared. In each group, the relationship between maternal serum leptin levels and TSH levels, BMI, newborn weight, and proteinuria was evaluated. The maternal serum leptin level was significantly higher in the preeclamptics than in the normotensive pregnant women. In the preeclamptic group, there was a strong positive correlation between maternal serum leptin levels and BMI (r =- 0.80; p < 0.001), a very weak positive correlation between maternal serum leptin levels and proteinuria (r = 0.305; p < 0.05), and a very weak inverse correlation between maternal serum leptin levels and birth weight (r = -0.377; p < 0.01). In the same group, there was no correlation between maternal serum leptin and serum TSH levels (r = 0.22; p > 0.05; Pearson correlation test). Leptin may be involved in the pathology of preeclampsia, and elevated maternal serum leptin levels may be a marker for the early stages of preeclampsia in pregnant women.

KEYWORDS

Preeclampsia - leptin - thyroid-stimulating hormone - body mass index

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