['Gestational diabetes mellitus (GDM) may be an expression of early metabolic syndrome. It is unknown whether weight and/or glucose parameters assessed at GDM pregnancies predict the risk of metabolic syndrome at the early postpartum period.', 'A group of women with GDM (N=1512) was evaluated at 3-11 months postpartum. Incident cases of diabetes were excluded. Antenatal measurements of GDM severity, third-trimester average glycated hemoglobin levels, prepregnancy body mass index (BMI), and increased gestational weight gain were considered. The predictive capability of these factors for postpartum metabolic syndrome was estimated.', 'The prevalence of postpartum metabolic syndrome was 10.9%. The three most common features of metabolic syndrome were low levels of high-density lipoprotein cholesterol (31.2%), high fasting glucose values (23.5%), and a high waist circumference (22.8%). The main predictors of metabolic syndrome were overweight or obesity prepregnancy and high antenatal fasting glycemia. This analysis was adjusted for family history of diabetes, prior GDM, dyslipidemia before pregnancy, chronic arterial hypertension, age, and smoking. The model area 95% confidence interval under the receiver operating characteristic curve was 0.87 (0.84-0.90) for metabolic syndrome presence. The risk for metabolic syndrome was progressively increased as risk factors were added (P<0.001 for trend). When obesity and high fasting glycemia were combined, a multiplied effect ensued.'] Are prepregnancy body mass index and prenatal fasting glucose effective predictors of early postpartum metabolic syndrome in Spanish mothers with gestational diabetes?