Appraisal of timing for oral glucose tolerance testing in relation to risk factors for gestational diabetes mellitus in pregnant women in a Nigerian Teaching Hospital

We investigated the pattern of common risk factors present in women undergoing oral glucose tolerance test (OGTT) in our center and to determine their relationship with time of presentation for the test. The records of women referred to the metabolic clinic for OGTT over a 1-year period were reviewed. Data available for retrieval included age, gravidity and gestational age, weight, and risk factors for gestational diabetes mellitus (GDM). Two hundred and fifty-three (253) pregnant women form the subject of this study. Thirty-five (13.8%) of the study population had GDM by WHO criteria. Approximately, 10% of the women were tested before 24 weeks and 87.6% of the women had at least one of the common risk factors as indication for testing. The most frequent indications were a history of previous macrosomic baby 77 (30.4%) and maternal obesity 61 (24.1%). Among the indications for OGTT, only a history of previous intrauterine fetal death was significantly associated with testing before 24 weeks of gestation. Early screening for GDM is not common in our environment. The presence of risk factors for GDM did not prompt early screening. Public enlightenment on the risk factors for GDM and the need for early screening should be vigorously pursued particularly for women at risk for GDM.