Postterm pregnancy is defined as 42 completed weeks (294 days) or more from the first day of the last menstrual period. Its incidence is about 10%.Ultrasound became the gold standard for determination of gestational age. Causes: inaccurate dating of pregnancy, use of nonsteriodal anti-inflammatory drugs, anencephaly and placental sulfatase deficiency.Complications: oligohydramnios, meconium aspiration syndrome, macrosomia and postmaturity syndrome. Antenatal assessment: nonstress and stress tests, ultrasound and Doppler. Management: routine induction of labor at 41 weeks resulted in reduced perinatal morbidity and mortality with out increase in the cesarean section rate.