Abstract:
Background: Early diagnosis of gestational diabetes mellitus (GDM) is crucial to prevent short term delivery risks
and long term effects such as cardiovascular and metabolic diseases in the mother and infant. Diagnosing GDM
in Sub-Saharan Africa (SSA) however, remains sub-optimal due to associated logistical and cost barriers for
resource-constrained populations. A cost-effective strategy to screen for GDM in such settings are therefore
urgently required. We conducted this study to determine the prevalence of gestational diabetes mellitus (GDM)
and assess utility of various GDM point of care (POC) screening strategies in a resource-constrained setting.
Methods: Eligible women aged ≥18 years, and between 24 and 32 weeks of a singleton pregnancy, prospectively
underwent testing over two days. On day 1, a POC 1-h 50 g glucose challenge test (GCT) and a POC glycated
hemoglobin (HbA1c) was assessed. On day 2, fasting blood glucose, 1-h and 2-h 75 g oral glucose tolerance test
(OGTT) were determined using both venous and POC tests, along with a venous HbA1c. The International Association
of Diabetes in Pregnancy Study Group (IADPSG) criteria was used to diagnose GDM. GDM prevalence was reported
with 95% confidence interval (CI). Specificity, sensitivity, positive predictive value, and negative predictive value of the
various POC testing strategies were determined using IADPSG testing as the standard reference.
Results: Six hundred-sixteen eligible women completed testing procedures. GDM was diagnosed in 18 women, a
prevalence of 2.9% (95% CI, 1.57% - 4.23%). Compared to IADPSG testing, POC IADPSG had a sensitivity and specificity
of 55.6% and 90.6% respectively while that of POC 1-h 50 g GCT (using a diagnostic cut-off of ≥7.2 mmol/L [129.6 mg/
dL]) was 55.6% and 63.9%. All other POC tests assessed showed poor sensitivity.
Conclusions: POC screening strategies though feasible, showed poor sensitivity for GDM detection in our
resource-constrained population of low GDM prevalence. Studies to identify sensitive and specific POC GDM
screening strategies using adverse pregnancy outcomes as end points are required
