- A normal oral glucose tolerance test (OGTT) during delivery hospitalization in women with gestational diabetes mellitus (GDM) may exclude type 2 diabetes (T2D).
Why this matters
- Less than half of women with GDM are screened for T2D postpartum.
- Patient-level data for women with GDM from 6 sites comparing immediate postpartum 75 g OGTT during delivery hospitalization vs routine 4- to 12-week postpartum OGTT.
- Funding: CDC, NIH.
- Of 319 screened at delivery, 52% (167) completed postpartum testing.
- Of 73 with normal glucose tolerance at delivery, 0% had T2D postpartum.
- Negative predictive value (NPV) of having T2D postpartum vs normal, impaired fasting glucose (IFG), or impaired glucose tolerance (IGT) at delivery, was 98.1% (95% CI, 94.5%-99.6%).
- NPV of any abnormal result (IFG, IGT, or T2D) postpartum compared with normal values at delivery was 75.3% (63.9%-84.7%).
- Sensitivity and positive predictive values of delivery OGTT:
- For T2D: 50% (11.8%-88.2%) and 30% (6.7%-65.3%).
- For any abnormal result: 69% (55.5%-80.5%) and 42.6% (32.4%-53.2%).
- Excluding IFG/IGT, compared with normal glucose results at delivery, NPV and specificity for postpartum T2D were 100% (93.5%-100%) and 96.5% (87.9%-99.6%), respectively.
- Patient characteristics varied across centers.
- High loss to follow-up.