Maternal serum screening marker levels in twin pregnancies affected by gestational diabetes

Purpose: To investigate the levels of maternal serum screening markers in the first and second trimester twin pregnancies, which subsequently developed gestational diabetes mellitus (GDM). Methods: 145 twin pregnancies were recruited in the first trimester. Stored blood samples were retrospectively tested for pregnancy-associated plasma protein (PAPP)-A, human chorionic gonadotrophin (hCG), placental growth factor (PlGF), placental protein (PP)13, α-fetoprotein (aFP) and inhibin A. Values were expressed in multiples of the gestation-specific median (MoMs) in singletons, adjusted for maternal weight and parity, as appropriate. Results: Twenty samples of first and second trimester were available from 11 twins who subsequently developed GDM and 219 samples from unaffected twins. The median PAPP-A level in the affected twins was 3.61 MoM compared with 2.46 MoM in unaffected twins (P < 0.001, Wilcoxon rank sum test, two tailed); significant results were found in both trimesters. The median PP13 was also increased but to a lesser extent. It was only statistically significant overall (P < 0.05) and in second trimester samples (P < 0.02). No other marker differed significantly. Logistic regression found that combining PAPP-A and maternal weight had a 55% detection rate for a 10% false-positive rate. Conclusions: Early prenatal marker evaluation in twin pregnancies can be also useful for predicting the risk for developing GDM and should be further investigated.