GDM Screen After 28 Weeks? Yay or Nay.

Here’s a real world clinical conundrum: A patient first presents for prenatal care in the 3rd trimester. As healthcare providers, we play a game of “catch-up” with routine serum tests ordered to make up for time lost. But what about specific pregnancy tests that are restricted to gestational age? Take, for example, GDM screening. Currently, traditional screening for GDM occurs at 24 to 28 weeks based on the original studies by O’Sullivan and Carpenter-Coustan. Or take this parallel, clinical scenario: A patient passes routine screening between 24 and 28 weeks, but in the 3rd trimester has suspected fetal macrosomia or new onset polyhydramnios. Should we rescreen these patients for GDM? As cut off values for the GDM screens are based on a 24 - 28 week pregnancy, we don’t really know what the cut off serum glucose levels should be after 28 weeks. And more importantly, does diagnosing GDM in the 3rd trimester improve maternal or neonatal outcomes? In this episode, we will walk down history’s timeline of data starting in 2001 and ending with a publication in 2022. We’ll discuss the findings of these publications (6 total) and at the end of the episode, I’ll give you my personal perspective on the subject.