Sex Hormone-Binding Globulin Level Enhances Prediction of Gestational Diabetes Mellitus in a Sub-Saharan African Population.

Background: The burden of Gestational Diabetes Mellitus (GDM) in the Sub-Saharan African region has been on the rise despite increased diagnosis and treatment. Current risk factor-based prediction approaches in the region lack strong predictive value, hence the need for effective early prediction and preventive interventions.

Aim: The aim of this study was to assess the diagnostic improvement in prediction of GDM by the addition of Sex Hormone-Binding Globulin (SHBG) assay to current approaches which assess early pregnancy maternal clinical risk factors in the study population.

Methods: This was a multi-centre hospital-based prospective observational study carried out over a period of 18 months in which serum SHBG levels were assayed and maternal clinical risk factors for GDM evaluated in a cohort of 271 pregnant women at 9 to 16 weeks gestational age. These participants were subsequently tested for GDM using a diagnostic 75g oral glucose tolerance test (OGTT) at 24 to 28 weeks of gestation.

Results: Clinical risk factor-based prediction approach had a diagnostic sensitivity of 59.6%, specificity of 69.4% and an area under the ROC curve of 0.758 (95% CI = 0.686, 0.830; p < 0.001). Following addition of SHBG assay to the maternal risk factors as predictors of GDM, the diagnostic sensitivity increased to 70.2%, specificity to 76.3% and there was a significant increase in the area under the ROC curve of 0.061 (95% CI = 0.006, 0.117; p = 0.030).

Conclusion: Current maternal clinical risk factor-based GDM prediction approach in early pregnancy lacks strong predictive value in the study population. Thus, addition of biochemical predictors like SHBG may improve early prediction of GDM and enable timely intervention.