Leptin and pre-eclampsia in black African parturients

Objective To measure serum concentrations of the hormone leptin during late pregnancy in Black African women with pre-eclampsia, healthy normotensive pregnant women as controls and healthy normotensive non-pregnant women; secondly, to explore the relationship between leptin and obesity. Design Observational, cross sectional study. Setting Antenatal clinics, antenatal wards, gynaecology out patient and family planning clinics of a tertiary hospital, Durban, South Africa. Population Pregnant and non-pregnant Black African women. Method Serum leptin was measured by a homologous radio-immunoassay technique. Simple anthropometric parameters were used to explore the relationship between leptin and obesity. In each group, leptin levels were compared between obese (body mass index, BMI greater than or equal to 30 kg M) and lean women. Main outcome measures Serum leptin concentrations, anthropometric parameters, mean blood pressures and proteinuria. Results There were 68 women with pre-eclampsia, 92 healthy normotensive pregnant women (controls) and 32 healthy normotensive non-pregnant women. Serum leptin levels were higher in pregnant compared with non-pregnant women [26.66 (1.96) and 25.89 (1.65) vs 17.97 (2.11) ng/mL, P = 0.02]. Weight and BMI showed the greatest correlation with leptin both in pregnant (r = 0.61 and r = 0.58, respectively) and non-pregnant women (r = 0.74 and 0.79, respectively). There was no significant difference in the mean concentrations of leptin between women with and those without pre-eclampsia [26.66 (1.96) vs 25.89 (1.65) ng/mL, respectively, P = 0.951. Conclusion Pregnancy is a hyperleptinaemic state. There is no difference in serum leptin levels between Black African women with pre-eclampsia and healthy normotensive pregnant women. Serum leptin concentration is largely determined by the degree of adiposity.