Maternal and Paternal Risk Factors for Cryptorchidism and Hypospadias: A Case-Control Study in Newborn Boys
Frank H. Pierik,1,2 Alex Burdorf,2 James A. Deddens,3 Rikard E. Juttmann,2,4 and Rob F.A. Weber1 1Department of Andrology and 2Department of Public Health, Erasmus MC, Rotterdam, the Netherlands; 3Department of Mathematical Sciences, University of Cincinnati, Cincinnati, Ohio, USA; 4Department of Child Health Care, Rotterdam Homecare Foundation, Rotterdam, the Netherlands
Abstract
Little is known on environmental risk factors for cryptorchidism and hypospadias, which are among the most frequent congenital abnormalities. The aim of our study was to identify risk factors for cryptorchidism and hypospadias, with a focus on potential endocrine disruptors in parental diet and occupation. In a case-control study nested within a cohort of 8,698 male births, we compared 78 cryptorchidism cases and 56 hypospadias cases with 313 controls. The participation rate was 85% for cases and 68% for controls. Through interviews, information was collected on pregnancy aspects and personal characteristics, lifestyle, occupation, and dietary phytoestrogen intake of both parents. Occupational exposure to potential endocrine disruptors was classified based on self-reported exposure and ratings of occupational hygienists based on job descriptions. Our findings indicate that paternal pesticide exposure was associated with cryptorchidism [odds ratio (OR) = 3.8; 95% confidence interval (95% CI), 1.1-13.4]. Smoking of the father was associated with hypospadias (OR = 3.8; 95% CI, 1.8-8.2). Maternal occupational, dietary, and lifestyle exposures were not associated with either abnormality. Both abnormalities were associated with suboptimal maternal health, a lower maternal education, and a Turkish origin of the parents. Being small for gestational age was a risk factor for hypospadias, and preterm birth was a risk factor for cryptorchidism. Because paternal pesticide exposure was significantly associated with cryptorchidism and paternal smoking was associated with hypospadias in male offspring, paternal exposure should be included in further studies on cryptorchidism and hypospadias risk factors. Key words: children, cryptorchidism, endocrine disruptor, environment, epidemiology, hypospadias, nutrition, occupational exposure, testis. Environ Health Perspect 112:1570-1576 (2004). [Online 3 September 2004]
Address correspondence to F.H. Pierik, Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Dr Molewaterplein 50, NL-3015 GE Rotterdam, The Netherlands. Telephone: 31-10-4087448. Fax: 31-10-4089449. E-mail: f.pierik@erasmusmc.nl
The Endocrine Modulators Study Group of the European Chemical Industry Council and the Nutricia Research Foundation are acknowledged for financial support. The sponsors of the study had no role in study design, data collection, data interpretation, or reporting.
The authors declare they have no competing financial interests.
