Acquired cryptorchidism is frequent in infancy and childhood.

Accurate prevalence data for acquired cryptorchidism are currently sparse and systematic prospective studies have not yet been reported. Our aim was to determine the prevalence of testicular ascent in childhood. In a prospective longitudinal population-based child cohort from Copenhagen, Denmark (1997-2007), testicular position was examined according to a standardised protocol in a total of 1072 boys, at birth (n = 1051), at 3 months (n = 983), 18 months (n = 888), 36 months (n = 790) and again once between 4 1/2 and 10 years of age (n = 509).

Risk factors for congenital cryptorchidism in a prospective birth cohort study.

Background: Risk factors for congenital cryptorchidism were investigated in a prospective birth cohort study in Denmark and Finland from 1997 to 2001.

Methodology And Principal Findings: In total, 2,496 boys were examined for cryptorchidism at birth (cryptorchid/healthy: 128/2,368) and three months old (33/2,215). Information on risk factors was obtained antenatally (questionnaire/interview) or at birth from birth records.

Hypospadias in a cohort of 1072 Danish newborn boys: prevalence and relationship to placental weight, anthropometrical measurements at birth, and reproductive hormone levels at three months of age.

Context: Hypospadias is one of the most frequent male congenital malformations and may be part of the testicular dysgenesis syndrome.

Objective: The aim of the study was to investigate the prevalence of hypospadias in Denmark and evaluate the relationship to anthropometrical measurements at birth and reproductive hormone levels at 3 months of age.

Design: A prospective cohort study was conducted with 3-yr follow-up (1997-2004).