Effect on fertility in rats of epididymal administration of indomethacin

Rods 2 mm in diameter and 8 mm long containing 25% or 50% indomethacin were implanted adjacent to each epididymis in rats of proven fertility. During the first 4 weeks after operation, fertility was reduced, but returned to normal at 5 to 10 weeks. The time of onset and duration of the effect were variable. Libido, ejaculation, and sperm motility were unimpaired. Drug-free Silastic rods had no effect on fertility. The results provide indirect evidence that prostaglandins have a functional role in the reproductive system of the male rat.