Gonadal findings in cryptorchid boys with Noonan's phenotype

7 patients with Noonan's syndrome, aged 5-16 years, complicated by bilateral cryptorchidism were examined by LH-RH and HCG stimulation tests, long-term HCG stimulation and testicular biopsy. 2 patients showed a good response and there was no effects in the remainder. Histological examination of the tests confirmed interstitial fibrosis in every case and showed abnormalities of the seminiferous tubules in 4 patients while in 1 patient the seminiferous tubules were composed of spermatocytes and spermatids. These hormonal and histological findings show different patterns of disturbance of the pituitary-gonadal system in male patients with Noonan's syndrome.