Introduction: There is an exponential rise in the occurrence of diabetes during pregnancy in South Asia. However data is sparse on the actual pre-gestational diabetes mellitus (PGDM) versus gestational diabetes mellitus (GDM) case-mix. The applicability of the WHO gold standard diagnostic tool–75g oral glucose tolerance test (OGTT)–and its optimal timing between 24-28 weeks gestation in South Asians is unknown.

Objective: To assess optimal timing for diagnosis, determine the case-mix of PGDM and GDM and their specific risk profiles, insulin needs and pregnancy outcomes among Sri Lankans.

Method: Prospective data was collected from consecutive women diagnosed with diabetes in pregnancy, at the Professorial Unit, De Soysa Hospital, Colombo from 1st January 2010,-28th Feb 2011. All were screened by an initial 2 hour post prandial (PPBS) at antenatal booking and risk stratified to determine the optimal timing of OGTT.

Results:(Total n= 140) GDM and PGDM occurred in 82% and 18% of patients respectively.