Effect of prenatal administration of androgen on the reproductive function in female rats.

Abstract

Studies were made on the effects of prenatal administration of androgen on the development of sexual function in female rats. Pregnant rats at the middle or late stage of gestation were injected subcutaneously with testosterone propionate (T. P.) or methyltestosterone (M. T.) and their embryos at the late stage of intra-uterine life were given a single direct injection of T.P. In pregnant rats, an injection of 3 or 6mg M. T. or T. P., given for 6 successive days beginning on the 12th or the 15th day of gestation did not affect ovarian function of the offspring, although it was effective in causing masculinization of the genital tract. The female young became pregnant by artificial insemination.An injection of 30 or 50mg of the hormones given to pregnant rats for 3 consecutive days between the 15th and the 17th day of gestation, and a single direct injection of 40μg of T. P. to fetuses on the 16th day of intra-uterine life gave rise not only to marked masculinization of the genital tract, but also to abnormal sexual function in female offspring. Many of these females exhibited constant cornification in vaginal smears and tended to display a persistent, opulatory response of low grade or failed to display any sexual reflex. The ovaries of these animals contained no normal nor freshly developing corpora lutea, but various types of follicles, some of which showed atresia.These results suggest that the prenatal administration of androgen does not always alter the ovarian activity of the female rats, though it effectively induces masculinization of the genital tract. However, with large doses, it may induce phenomenon corresponding to androgen sterility in later life.