Gestational diabetes mellitus [GDM] is fast becoming a common pregnancy complication in developing countries and is undoubtedly associated with increased adverse maternal, perinatal and long term outcomes. The WHO 2013 glycemic criteria for diagnosis of GDM has undoubtedly led to a significant rise in prevalence globally however, prevalence using the above criteria is still lacking in the African continent. Screening for GDM is important for diagnosis due to its asymptomatic nature however, the recommended screening tool- OGTT may not be readily available or expensive in low resource rural hospitals that usually have a large obstetric population. Maternal waist circumference has been validated and a cheap, reliable and readily available tool to predict cardio-metabolic risks outside pregnancy and recently GDM. Unfortunately, studies on this subject are lacking in sub-Saharan Africa. OBJECTIVES To determine the incidence of GDM using the WHO 2013 criteria, if early pregnancy maternal waist circumference could predict the risk of GDM and compare its performance with BMI, neck circumference, hip circumference and W: H ratio in predicting GDM among pregnant women attending the antenatal clinic of UCH, Ibadan. METHODOLOGY A prospective cohort study was carried out among 292 pregnant women between 8 to 13 weeks gestational age at the antenatal clinic of the University College Hospital, Ibadan from June 2020 to January 2021. Anthropometric measurements including waist circumference were measured at 8 to 13 weeks and a 75g OGTT was performed on all study participants at 28 weeks gestation. xiv Gestational diabetes mellitus was diagnosed using the WHO 2013 criteria. Based on the OGTT results, subjects were allocated into two groups; GDM and Normal groups. Waist circumference, BMI, neck circumference, hip circumference and W:H ratio sensitivities, specificities, odds ratios and 95% confidence intervals were estimated. Their receiver operating characteristic curves was generated and analysed.