First trimester pregnancy-associated plasma protein-A in pregnancies complicated by subsequent gestational diabetes

Objective: To compare routine first trimester biochemical and ultrasound markers in pregnancies complicated by gestational diabetes with those of a control group. Methods: First trimester data including the screening test for Down syndrome were retrieved from a computer data base. Clinical data were recorded at delivery. A multivariate quantile regression model was used to analyze the association between first trimester data and subsequent clinical outcomes in a case-control study design. Results: In the group of women who developed second trimester gestational diabetes, both first trimester median (1494 vs 2225 mU/L, P <0.001) and adjusted multiple of median pregnancy-associated plasma protein-A (PAPP-A) concentrations (1.2 vs 0.7, P <0.001) were significantly lower than in the control group. Differences between observed and expected crown-to-rump length expressed in mm was lower in women destined to develop gestational diabetes than in the control group (0.2 vs 1.4 mm, P <0.005). In multivariate models, first trimester maternal PAPP-A concentrations correlated independently and inversely to pregestational body mass index (BMI, P = 0.004), subsequent gestational diabetes (P <0.001) and pregnancy complications (P = 0.036). Conclusions: First trimester PAPP-A concentrations were lower among pregnant women with subsequent gestational diabetes than in the control group.