The purpose of a new study published PLoS One was to determine the relative contribution of risk factors such as poor glycemic control obesity and excessive gestational weight gain for large for gestational age LGA in women with diabetes mellitus type 1 T1DM and type 2 T2DM after controlling for important confounders such as age smoking and parity. This retrospective chart review analyzed the medical files of pregnant women with T1DM and T2DM who attended the antenatal care program at Sk ne University Hospital between 2006 and 2016. Glycated hemoglobin HbA1c was used as a measure of glycemic control. LGA was defined as birth weight 2 standard deviations of the mean. During the study period 308 singleton pregnancies were identified in 221 women with T1DM and in 87 women with T2DM. The findings revealed that the rate of LGA was 50 in women with T1DM and 23 in women with T2DM. Gestational weight gain and second trimester HbA1c were risk factors for LGA in T1DM pregnancies while gestational weight gain was a risk factor in T2DM pregnancies independent of body mass index. Hence it was concluded that gestational weight gain was associated with LGA in women with T1DM and T2DM independent of maternal body mass index. The findings suggest that monitoring and regulation of gestational weight gain is important in the clinical care of these women to minimize the risk of fetal overgrowth.