Assessment of relationship between anthropometric measurements and reproductive hormonal profiles, among females of childbearing age at a tertiary health facility in Nigeria

Background: Increasing prevalence of overweight and obesity has profound impacts on health generally, including the reproductive system. Traditionally, pear body shapes, from narrow waist and wide hip circumferences, have been associated with high fecundability among females. Although this has been scientifically demonstrated by a number of researches only a few of these investigations were conducted with black women in Africa who were of reproductive age. Objectives: The objectives of the study were to compare the mean reproductive hormone levels between the different waist-to-hip ratio (WHR) and body mass index (BMI) categories and also to determine the correlations between the two anthropometric measurements and the reproductive hormones in a black African population. Materials and Methods: It was an analytical cross-sectional study of 180 females of a childbearing age. The WHR and BMI were measured as per standard recommendations. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin, estradiol, day-21 progesterone, and testosterone were assayed. Results: A majority of the research participants were within the age group 21–30 years. Thirty three percent (33%) and 28.9% of participants were overweight and obese, respectively, using BMI compared with 26.7% and 20%, respectively, using WHR. Seventy six point nine percent (76.9%) of participants with an optimal BMI range ovulated with 61.5% having adequate luteal phase support compared with 75% and 54.2%, respectively, using WHR. Day-21 serum progesterone and serum estradiol were significantly negatively correlated with WHR and BMI (P < 0.05). BMI, however, showed a better correlation than WHR (r = -0.535 vs. -0.397; P = 0.001 vs. 0.008, respectively). Gonadotropins were significantly lower among overweight and obese groups for both BMI and WHR (P < 0.05), but only WHR showed moderately positive significant correlation with gonadotropins (LH: r = 0.050 vs. r = 0.215, P = 0.003, respectively; FSH: r = 0.159 vs. r = 0.431, P = 0.001, respectively), same as serum testosterone (r = 0.580 vs. r = 0.611, P = 0.002, respectively). Conclusions: Anthropometric measurements can serve as objective clues to functionality and optimal concentrations of reproductive hormones. Weight control should therefore aid the optimization of reproductive hormones and fertility among females of reproductive age.