Gestational diabetes mellitus (GDM) is associated with an increased risk of maternal and fetal/neonatal complications. All of the statements about congenital anomalies in diabetes mellitus are true, EXCEPT:

Single umbilical aery is more common in twins and in babies born of diabetic mothers or in polyhydramnios. Free oxygen radical excess in diabetes mellitus is one of the proposed factor associated with teratogenesis. 6-10% cases are associated with major congenital malformations. It is related to the severity of diabetes affecting organogenesis in the first trimester. When diabetes is first detected during pregnancy and cannot be controlled by diet alone it should be treated with insulin. Ref: Textbook of Obstetrics by DC Dutta, 6th edition, Page 220.