Real-world screening for diabetes in early pregnancy: Improved screening uptake using universal glycated haemoglobin

To improve perinatal outcomes, screening for hyperglycaemia using 75 g oral glucose tolerance test (OGTT) is recommended for all pregnant women at 24-28 weeks gestation (routine), and earlier if high-risk. Screening coverage for remote and Aboriginal Australian women is less than ideal. This study examined OGTT completion (early and routine) by women from rural and remote Western Australia compared with early glycated haemoglobin (HbA_1c).

In 2015-2018, 27 primary health care sites recruited 600 (233 Aboriginal) women aged ≥16-years, without pre-existing diabetes, who delivered >30-weeks gestation. All women presenting <20-weeks gestation (541) were offered an early study HbA_1c. Early OGTTs were requested at the discretion of the local clinician, with routine OGTT offered at 24-28 weeks.

HbA_1c uptake was high (85.7% Aboriginal, 86.4% non-Aboriginal); OGTT completion in Aboriginal women was low (early OGTT: 38.6% v 69.6% non-Aboriginal, P < 0.001; routine OGTT: 44.5% v 84.7% non-Aboriginal, P < 0.001). Aboriginal women with both early tests had HbA_1c completed 3-weeks prior to OGTT (9.6 ± 3.5 v 12.5 ± 3.5 weeks gestation, P < 0.001).

Universal early pregnancy HbA_1c appears feasible as an early screening test for women at risk of hyperglycaemia in pregnancy and would expedite and increase screening in Aboriginal women compared to an early OGTT.