An intramuscular injection of 5 mg dinoprost caused a discharge of uterine fluid (cloudburst) in 49 cases of hydrometra in goats during the breeding seasons of 1988, 1989 and 1990. A spontaneous oestrus after the cloudburst was allowed to occur in 20 of the goats; in nine (45 per cent) of them a hydrometra recurred, three conceived at the first oestrus and eight returned to oestrus. Oestrus was induced in 29 other cases by means of a second intramuscular administration of 5 mg dinoprost, 12 days after the cloudburst. In this group a hydrometra recurred in only one goat, 14 goats (48 per cent) conceived at the first oestrus and 14 returned to oestrus. Of the animals in which a pseudopregnancy occurred once or more during the same breeding season, 85 per cent became pregnant, compared with 97 per cent of unaffected older goats. The mean number of kids of the goats that became pregnant and kidded after treatment for hydrometra was 2.0 compared with 2.3 for unaffected animals. The results indicate that a single administration of prostaglandin is not a satisfactory therapy for a hydrometra, but that reproductive performance improves when a second injection is given 12 days after the cloudburst.