Clinical Risk Factors and First Gestational 75 g OGTT May Predict Recurrent and New-Onset Gestational Diabetes in Multiparous Women

<b>Background</b>: Women who experience gestational diabetes mellitus (GDM) during their first pregnancy are at a high risk of developing GDM again in subsequent pregnancies. Even mothers with no previous history of GDM may develop the condition in a new pregnancy. <b>Methods</b>: In this retrospective cross-sectional observational study, 759 multiparous women tested for GDM in two successive pregnancies using the 75 g OGTT (IADPSG criteria) were enrolled. The OGTT was performed at 24-28 weeks' gestation or earlier if there was a history of GDM. Participants were categorized into four groups: women with normal glucose tolerance (NGT) in both pregnancies (<i>n</i> = 493), women with a first occurrence of GDM in their second pregnancy (<i>n</i> = 74), women with non-recurrent GDM in their second pregnancy (<i>n</i> = 92), and women with recurrent GDM in their second pregnancy (<i>n</i> = 100). <b>Results</b>: Intergroup comparisons revealed clinical predictors of GDM in the first pregnancy (family history of type 2 diabetes, PCOS, advanced maternal age, pregravid obesity) and in the second pregnancy (interpregnancy BMI gain), as well as predictors of recurrent GDM (pregravid obesity, PCOS). A positive correlation was observed between the OGTT glucose levels of consecutive pregnancies. Adjusted logistic regression indicated that a higher 1-h post-load glucose level (≥130 mg/dL) during the first pregnancy significantly increased the likelihood of new-onset GDM in the second pregnancy (OR: 2.496), whereas a higher 2-h post-load glucose level (≥153 mg/dL) at the first diagnostic OGTT increased the likelihood of recurrent GDM (OR: 2.214). <b>Conclusions</b>: Clinical risk factors and post-load glucose levels during the first gestational 75 g OGTT can help predict new-onset or recurrent GDM in multiparous women.