Impaired glucose tolerance and pregnancy outcome in Chinese women with high body mass index

To determine if impaired glucose tolerance (IGT) impacts on the outcome of singleton pregnancies in Chinese women with a high (>26 kg/m(2)) body mass index (BMI), a retrospective case-control study was performed on 128 women with IGT and 128 controls with normal oral glucose tolerance test results, who were matched for pre-pregnancy BMI (within 0.1 kg/m(2)) and delivered w ithin the same 3 year period, The IGT group was older, with more multiparae , a higher incidence of previous gestational diabetes mellitus, higher book ing haemoglobin and fasting glucose concentrations, but no difference in th e pre-pregnancy weight, gestational weight gain, or weight or BMI at delive ry. There was no difference in the obstetric complications, mode of deliver y, or the gestational age or mean infant birthweight. However, the birthwei ght ratio (relative to mean birthweight for gestation), incidence of large- for-gestational-age (birthweight >90th percentile) and macrosomic (birthwei ght greater than or equal to 4000 g) infants, and treatment for neonatal ja undice, were significantly higher in the IGT group. The results suggest tha t some of the complications attributed to gestational diabetes mellitus are probably related to maternal weight excess/obesity in the affected subject s, but IGT could still affect infant birthweight outcome despite diet treat ment which has normalized gestational weight gain.