The most serious hazard of gestational diabetes is shoulder dystocia, which sometimes is complicated by Erb's palsy and maternal lacerations. This risk is linked to fetal weight, and is more frequent in cases of diabetes. So, a caesarean section performed when macrosomia is present is required and an induction of labor before severe macrosomia is proposed. Unfortunately, estimation of fetal weight is imprecise in spite of formulas from fetal parameters. Abdomen circumference (AC) alone is as effective as complex formulas. So, it is proposed to perform an elective section when AC is equal or above 38 cm, and to induce labor, after 38 weeks of gestation, for limiting the risk of macrosomia when AC is between 35 and 38 cm. Induction is also proposed when pregnancy is complicated by hypertension or when fetal heart septal hypertrophy occurs. The management of gestational diabetes means a strict control of glycemia, which can reduce macrosomia and the need for cesarean section or induction of labor.