Abstract
The action of trenbolone acetate, a synthetic anabolic steroid, on ovarian function was investigated in the guineapig. Certain comparisons were made with testosterone, the naturally occurring androgen, administered as the phenylpropionate ester. Two milligrammes trenbolone acetate per kg given subcutaneously on alternate days for 20 days blocked oestrous cyclicity and ovulation in 9 of 10 animals. A similar effect was shown by 2·2mg of testosterone phenylpropionate. Treatment of trenbolone acetate-treated animals with exogenous gonadotrophins suggested that the production of follicle-stimulating hormone had been suppressed. Signs of abnormality were seen in the livers of animals receiving 2 mg trenbolone acetate and 2·2 mg testosterone phenylpropionate.