The problems of multiple pregnancy and polyhydramnios pose a unique challenge in the practice of obstetrics. This chapter describes the incidence, etiopathology and the clinical diagnosis of each of the two conditions. The practical problems encountered in the management strategies have also been outlined. The most frequently used method to determine the zygosity of twins is the examination of the placenta at birth. The finding of a monochorionic placenta is unequivocal proof of monozygosity. Ultrasonography is vital in the confirmation of twins, for the diagnosis of chorionicity and accurate measurement of gestational age. It also helps to diagnose intrauterine growth restriction, discordant twins, twin to twin transfusion syndrome, and intrauterine fetal death. Since preterm delivery is necessary in a large majority of patients with twin-to-twin transfusion, corticosteroids should be used to accelerate fetal lung maturity at the earliest. Umbilical cord problems are more frequent in twin pregnancies—these include single umbilical artery and velamentous insertion of the cord. Cord entanglements, cord prolapse and torsion due to focal absence of Wharton’s jelly are more common in monoamniotic twins. If vaginal bleeding occurs suggesting abruptio placentae or there are late decelerations indicating fetal distress, delivery should be immediate by forceps or cesarean section or breech extraction. Epidural anesthesia administered by an experienced anesthetist is preferable. Polyhydramnios is a pathological condition characterized by an excessive accumulation of amniotic fluid, usually more than 2000 ml. The differentiation between acute versus chronic polyhydramnios depends on the week of onset, rate of uterine growth and period of delivery. Placental Chorioangiomas and the circumvallate placenta could cause polyhydramnios. Antepartum maternal problems include the risk of developing pregnancy-induced hypertension, preterm labor and prelabor rupture of membranes. There may be marked cardiorespiratory embarrassment. The neonatologist should evaluate the newborn to exclude congenital anomalies, especially, esophageal atresia by the passage of a soft rubber catheter into the stomach.