Prostate hypoplasia is the congenital abnormality of a small (or absent) prostate gland. Often associated with other abnormalities of the urogenital system. Often due to abnormality in mesenchymal cells and associated with prune belly syndrome. Observed in 5ñ-reductase 2 deficiency in which impaired 5ñ-dihydrotestosterone (DHT) synthesis impairs prostate development which is DHT dependent.