During the period from 1 January 1974 to 31 December 1975, 71 therapeutic midtrimester abortions were performed at Groote Schuur Hospital by the intra-uterine administration of prostaglandins. Both the extra- and intra-amniotic routes of administration proved to be uniformly successful but the latter route was associated with fewer side-effects. The intra-amniotic administration of 30 mg prostaglandin F2alpha in combination with 60 g urea is the recommended method for achieving midtrimester abortion. If the method described is strictly adhered to, it provides a single-dose regimen which is uniformly successful and which is associated with few complications.