Increasing prevalence of hypospadias associated with various perinatal risk factors in chinese newborns.

OBJECTIVES

To evaluate the increasing trends of hypospadias and identify some of the perinatal risk factors that might be involved in Chinese newborns.

METHODS

The records from the neonatal intensive care unit were reviewed during a 10-year period. A case-control study was performed to compare the intrauterine growth status of the infants. Logistic regression analysis was used to assess the independent contribution of maternal factors to the risk of hypospadias.

RESULTS

Of 8364 male infants, 75 were diagnosed with hypospadias at birth. The overall incidence trend increased during the 10 years. Hypospadias was present more frequently in infants born small for gestational age (P < .0001), those with a very low birth weight (P < .0001), and preterm infants (P < .0001). An increased risk of hypospadias was found when mothers had had multiple births (odds ratio [OR] 2.58), were living in the countryside (OR 1.60), were engaged in outdoor (OR 1.62) or agricultural (OR 2.41) activities, and when the pregnancy was complicated by hypertension (OR 4.75), pre-eclampsia (OR 7.70), or hepatitis B antigen carrier status (OR 2.68). Maternal age (OR 0.98), parity (OR 0.93), and maternal occupational exposure as a housewife (OR 1.02), businesswoman (OR 1.1), or industrial/production worker (OR 0.84) were not associated with the risk of hypospadias.

CONCLUSIONS

We found an increasing trend in the incidence of hypospadias among male infants in Chinese population in the past 10 years. Hypospadias was shown to be associated with poor intrauterine growth, maternal multiple births, living in a rural area, working outdoors and agricultural activities, hepatitis B antigen carrier status, hypertension, and pre-eclampsia of pregnancy.