After approximately 2 weeks menstrual delay (positive Pregnosticon Tests) "menstrual induction" was attempted in 75 gravidas by repeated vaginal application of a gel, containing 200 or 400 mug/ml ICI 81008. After approximately 10 minutes, following the 1st vaginal delivery of 400 mug ICI 81008, the uterus responded to this PGF2alpha analogue with sustained contracture. The highest success rate in induced bleeding (93%) and pregnancy termination (79%), without supportive therapy, was achieved when 400 mug ICI 81008 was administered 2 to 5 times at 4 hour intervals. Those gravidas (21%), who failed in induced menstruation, or stopped bleeding within 24 hour- after treatment, had positive Pregnosticon Tests on day 14 and were curetted. The side effects, mostly vomiting and increased blood pressure, were transient and subjectively and medically acceptable. While the vaginal application of the drug is apparently less effective than the intrauterine (1), it has the advantage of simple delivery and the potential of self-administration.