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 ≥ 30 kg m−2) 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= 0.95].
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.