Are women with gestational diabetes being screened for type 2 diabetes following pregnancy? A nationwide retrospective cohort study in Aotearoa New Zealand.

• 53.3% of women received appropriate screening within six months postpartum. • Inequity in postpartum type 2 diabetes screening was identified for Māori women. • Postpartum type 2 diabetes screening varied widely by geographic region. • Administrative data are viable for monitoring postpartum type 2 diabetes screening. To estimate the proportion of women with a first episode of gestational diabetes mellitus (GDM) in Aotearoa (New Zealand) who received postpartum screening for type 2 diabetes mellitus (T2DM). Data from 941,468 pregnancies occurring between 2005 and 2015 were linked with laboratory, community pharmacy, and hospital discharge data from the Ministry of Health's National Collections to identify a cohort of women who had a first episode of GDM (n = 14,443). Proportions receiving a glycated haemoglobin (HbA1c) test or oral glucose tolerance test (OGTT) during the first year postpartum were estimated overall, and by calendar year, ethnic group, age, deprivation, and region. Overall, 40.9% (95% CI 40.1–41.7%) received an HbA1c test or OGTT within 3 months, 53.3% (52.5–54.1%) within 6 months, and 61.0% (60.2–61.8%) within 12 months postpartum. Screening proportions within 12 months were stable over time. Indigenous Māori were less likely to receive screening within 6 months postpartum (35.0% [33.1–37.0%]) than other ethnic groups, as were younger women and those with higher deprivation. There were marked variations by region (between 15.3% and 67.5%). Postpartum T2DM screening was low over the period studied, with substantial ethnic and regional inequities across New Zealand. [ABSTRACT FROM AUTHOR]