TRANSPORT OF OESTROGENS IN SEMEN TO THE FEMALE RAT DURING MATING AND ITS EFFECT ON FERTILITY

Abstract

Summary. Male rats treated with oestradiol or Carbestrol®* for 8 days were found to be incapable of impregnating normal females. Oestrogen treatment was associated with a higher incidence of headless spermatozoa recovered from vaginal smears. Hypertrophy and hyperplasia of uterine tissues along with a significant increase in uterine weights were observed on Day 1 of pregnancy. Alteration in ova transport was first observed on Day 2 when fewer cleaved ova than expected were recovered from the oviducts. No ova were recovered from the oviducts or uteri on Days 3 or 4 while the expected numbers were flushed from controls. It is concluded that such treatment leads to accumulation of oestrogens in semen, which, following coitus, is sufficient to alter events essential for conception.