&NA; Extra‐amniotic saline instillation using a 26‐gauge Foley catheter and vaginal application of prostaglandin E2 (PGE2) were compared. Among 52 cases treated with extra‐amniotic saline instillation, the mean Bishop score increased from 1.7 to 7.8 in a mean of 2.8 hours. In all cases but one, an increase of the Bishop score of three or more points occurred during a 6‐hour period. Prostaglandin E2 tablets (3 mg) applied in the posterior vaginal fornix (once or twice) resulted in an increase in the Bishop score of three or more points in 39 of 54 cases during the 12‐hour study period. The mean Bishop score in these “successful” ripenings using PGE2 increased from 1.9 to 5.6 points during a mean time of 8.5 hours. No severe side effects were registered in either procedure. (Obstet Gynecol 73:938, 1989)