Login to Access Video or Poster Abstract: MP66-09
Sources of Funding: None

Introduction

Several studies have identified risk factors for undescended testis (UDT) and hypospadias (HYP), but few have adjusted their estimates using multivariate modeling techniques. The objective of this study was to utilize an administrative database to measure the adjusted estimates of known maternal and fetal risk factors for UDT and HYP, while accounting for the effect of having a previous sibling with these anomalies.

Methods

This retrospective population-based cohort study used several linked provincial databases held at the Institute for Clinical Evaluative Sciences, in the province of Ontario, Canada, to identify all males born between 1997-2007 with a diagnosis of UDT and HYP. To ensure validity of the diagnosis, the cohort only included patients who had a surgical procedure for UDT or HYP on follow up. Baseline maternal and fetal risk factors obtained using ICD 9-10 codes, were assessed using generalized estimating equations with a logit link, adjusting for clustering amongst mothers with previous children with UDT or HYP.

Results

In 5830 boys with UDT, multivariable analysis identified prematurity and small for gestational age, associated HYP, multiple gestation, gestational hypertension, use of assisted fertility techniques, increased maternal age, babies born to immigrant mothers and a need for caesarean section as significant risk factors. In 2722 boys with HYP, significant risk factors included small for gestational age and prematurity, associated UDT, multiple gestation and babies born to immigrant mothers. After adjusting for a previous sibling with UDT, all these maternal and fetal risk factors lost statistical significance, except associated anomalies like DSD (OR: 82.3 95% CI 54.4-124.5 p<0.01) or HYP (OR: 2.04 95% CI 1.0-4.1 p= 0.04). After adjusting for a previous sibling with HYP, only small for gestational age (OR: 1.80 95% CI 1.03-3.1 p=0.03) and associated UDT (OR: 7.09 95% CI 4.87- 10.33 p<0.01) remained as significant risk factors.

Conclusions

While a combination of maternal and fetal factors were identified as risk factors for UDT and HYP in our multivariable analysis, after adjusting our analysis for individuals with a previous sibling with these conditions, only few fetal factors remained as significant risk factors. These results indicate that an underlying genetic predisposition for HYP and UDT could be a confounding factor when analyzing studies, which estimate risk factors for UDT and HYP without accounting for clustering in mothers who have had children with these anomalies

Funding

None