RISK-FACTORS FOR CRYPTORCHIDISM - A NESTED CASE-CONTROL STUDY

A nested case-control study of cryptorchidism (i.e. undescended testic les) was undertaken as part of a hospital-based cohort study of 6699 s ingleton male neonates in New York City. Since some of the cryptorchid infants experienced spontaneous descent of their testes, separate ana lysis was performed for this third group of 'late descenders' (n = 140 ). Cases (n = 63) represented infants whose testes remained undescende d at the one year assessment. Controls (n = 219) represented the next male infant who was delivered immediately after an infant who was cryp torchid at birth. The only independent risk factors for cryptorchidism were Asian ethnic group (adjusted odds ratio (OR) = 3.90, 95% confide nce interval (CI) = 1.22-12.41), swollen legs or feet during pregnancy (adjusted OR = 2.16, 95% CI = 1.15-4.04), a family history of cryptor chidism (adjusted OR = 4.32, 95% CI = 1.91-9.80), low birthweight (adj usted OR = 4.10, 95% CI = 1.39-12.08), and use of analgesics during pr egnancy (adjusted OR = 1.93, 95% CI = 1.03-3.62). Multiple logistic re gression analysis was also performed to identify those factors that we re associated with late testicular descent. In this analysis the indep endent risk factors were black or Hispanic ethnicity (adjusted OR = 2. 05, 95% CI = 1.09-3.83), a family history of cryptorchidism (adjusted OR = 4.25, 95% CI = 1.84-9.78), consumption of cola-containing drinks during the pregnancy (adjusted OR = 2.09, 95% CI = 1.10-3.99), a low b irthweight delivery (adjusted OR = 9.78, 95% CI = 3.39-28.20), and pre term birth (adjusted OR = 4.01, 95% CI = 1.66-9.70).