Women with a history of gestational diabetes mellitus who go on to develop type 2 diabetes are diagnosed almost 13 years earlier on average and are more than six times as likely to be diagnosed before age 40, new research suggests.

The unpublished Danish study found that 40% of women with previous gestational diabetes mellitus (GDM) were under age 40 at type 2 diabetes (T2D) onset compared with 6% of women without previous GDM.

The authors from the Steno Diabetes Center network say it highlights the importance of postpartum follow-up and ongoing screening of women who have had GDM.

They compared women diagnosed with T2D from 2010 with (n=173) and without (n=2692) a history of GDM in terms of age at diagnosis, clinical features and associated complications.