Prolongation of pregnancy and survival of twin B after loss of twin A at 21 weeks' gestation.

At 21 weeks' gestation premature rupture of the membranes led to unavoidable delivery of an immature first twin (390 gm) who died shortly after birth. The placenta was left undisturbed. Twin B was confirmed to be alive within an intact second sac. Directly after delivery of twin A tocolysis was begun and cervical cerclage was undertaken. Pregnancy was successfully prolonged, which enabled the second fetus to remain in utero and grow for another 12 weeks. Onset of active labor resulted in delivery of a healthy 1750 gm female infant at the beginning of 33 weeks' gestation. The neonatal care was benign and the infant left the hospital in excellent condition after 4 weeks. The case is presented in detail and discussed with respect to the aggressive approach undertaken to prolong gestation.