Estimation of testosterone and androstenedione in the plasma and testes of cryptorchid offspring of mice treated with oestradiol during pregnancy.

The injection of pregnant mice with 5 mg oestradiol dipropionate induced a high proportion of bilateral cryptorchidism in the male offspring. The ectopic testes were reduced in size and occupied one of three different positions in the abdomen: pararenal, paravesicular or inguinal. The seminal vesicles were found to be similarly reduced in size whereas the adrenals and pituitaries appeared to be unaffected. The total content of testosterone was reduced in the pararenally placed gonads but was not significantly different from that of the controls when the testes were in the inguinal region. The content of androstenedione was not significantly altered. The concentration of both hormones, however, was increased in all cases. Plasma testosterone levels were lower in all the offspring of treated mothers, especially in those with high ectopia.