Serum Prolactin Levels and Clinical Features of Hyperprolactinaemia in Obese and Non- Obese Infertile Women in Kano, Northwest Nigeria: A Comparative Study

Background: Hyperprolactinaemia can cause infertility. Serum prolactin and clinical features of hyperprolactinaemia may vary between obese and non-obese infertile women. Identifying the differences may inform changes in the management of obese women with hyperprolactinaemia. This study aimed to compare the serum prolactin levels and the clinical features of hyperprolactinaemia in obese and non-obese infertile women in Kano.

Methodology: This was a comparative cross-sectional study comprising 160 obese infertile women (study group) and another 160 non-obese infertile women (control group). Participants were recruited in the gynaecology clinics of Aminu Kano Teaching Hospital (AKTH) and Murtala Muhammed specialist Hospital (MMSH). Serum prolactin and clinical features of those with hyperprolactinaemia were analysed using SPSS 23. P-values ≤ 0.05 were considered significant. Odd ratios at 95% confidence were calculated.

Results: The mean serum prolactin levels were 28.18 ± 10.53ng/ml and 17.50 ± 8.00 ng/ml in the obese and non-obese women respectively (P=0.0001). All categories of hyperprolactinaemia were more common (P=0.001) amongst the obese infertile women. The prevalence of hyperprolactinaemia was 37.5% and 18.1% in the obese and non-obese arms respectively (P=0.0001). However, 23.1% obese hyperprolactinaemic infertile women presented with galactorrhoea compared to 64.0% of the non-obese counterparts (P= 0.0001). Abnormal menstrual flow and galactorrhoea were observed more in moderate-markedly elevated serum prolactin level as seen in 65.2% and 69.6% respectively compared to those with mildly elevated serum prolactin level.

Conclusion: Obese infertile women have higher baseline and prevalence of hyperprolactinaemia than their non-obese counterparts. However, non-obese hyperprolactinaemic infertile women presented more with galactorrhoea.