Prevalence of gestational diabetes mellitus in a Suburban District in Sri Lanka: a population based study

Introduction GDM is a leading metabolic cause of morbidity to mother and offspring. Determining its prevalence is important for health planning and implementation.

Objective Assess prevalence of GDM in the District of Gampaha.

Methods Community based cross-sectional study was conducted in women attending field-based ante-natal clinics in two Medical Officer of Health (MOH) areas between January 2014 to March 2015. Consecutive women were recruited by cluster sampling with probability proportionate to size using strict exclusion criteria. GDM diagnosis was based on fasting 75 g OGTT, WHO 1999. All responders underwent 2 hr PPBS in first trimester- >200 mg/dl with symptoms identified as abnormal, probably diabetes in pregnancy (DIP); those >120 and <200 mg/dl proceeded to OGTT before 16 weeks POA; all negatives were tested by OGTT between 24-28 weeks. Negatives for GDM at 24-28 weeks underwent OGTT between 32-36 weeks; venous plasma glucose tested by accredited laboratory.

Results Sample consistedof 160, non-response 4.2% (67); 1533 underwent 2 hr PPBS with 40 exceeding 120mg: 4 >200 mg diagnosed as GDM / DIP, 36 (PPBS >120 < 200 mg) underwent OGTT before 16 weeks with 15 GDM. One hundred and thirty four (8.38%) miscarried including one with early abnormal OGTT. Of 1381 eligible for OGTT (24- 28 weeks) 150 had GDM (10.86%). Only 344 (27.94% of normal 1231) consented for third trimester OGTT, of whom 25 had GDM- yielding a total of 194 with GDM (13.9%).

Conclusion The current community prevalence of GDM in the suburban Gampaha District, Sri Lanka is high.