Authors
Wiedner, IS., Møller, H., Jensen, TK., Skakkebæk, NE.

Title
Cryptorchidism and Hypospadias in the Sons of Gardeners & Farmers

Journal
Environmental Health Perspectives Volume 106, Number 12, December 1998

Summary
Recent animal studies have shown that estrogen exposure during pregnancy can result in cryptorchidism and hypospadias in progeny. A number of chemicals used in agriculture have been studied for their estrogenic effects and hormone activity. Therefore, it was hypothesized that maternal exposure to estrogenic pesticides through gardening and farming could potentially augment the risk of these urogenital malformations in male offspring.

Wiedner et al conducted a register-based case-control study that explored the hypothesis that paternal and maternal exposure to pesticides, through farming and gardening, increases the risk of cryptorchidism and hypospadias in male offspring. A total of 6 177 cases of cryptorchidism, 1345 cases of hypospadias, and 92 cases of both were identified. Cases included all males discharged between 1983 and 1992 with a diagnosis of cryptorchidism or hypospadias and all variants of these conditions, as defined by the WHO International Classification of Disease, 8th and 10th versions, as well as those who had an operation specifically for cryptorchidism or hypospadias. Cases were established through The Danish National Patient Register discharge data and the Danish Malformation Register, which records malformations observed in the first year of life. All risk factor information was obtained from the Fertility Database at Statistics Denmark as well as a control group (n=23, 272) that was chosen at random, excluding incidentally occurring cases. Parental occupation data on farming and gardening was drawn from tax authority information sheets. Gardening included work in greenhouses, outdoor gardening, orchards, and nurseries. Analysis was done using contingency tables and unconditional logistic regression. Multivariate analysis included several confounding variables including the year of birth, as this increased the probability of being diagnosed with cryptorchidism or hypospadias.

The sons of women working in farming or gardening were found to be at increased risk of cryptorchidism (OR=1.38, CI= 1.10-1.73). There was a prominent risk in the sons of women working in gardening (OR=1.67, CI=1.14-2.57) however, the prevalence of female gardeners was very low (0.4%) and the proportion of cases of cryptorchidism attributable to maternal occupation in gardening was near only 0.3%. Maternal occupation in gardening or farming did not increase the risk of hypospadias in male offspring and paternal occupation had no effect on the risk of either birth anomaly. To evaluate the occurrence of misdiagnosis, analysis was repeated on only those cryptorchidism cases that had a surgical record of treatment for cryptorchidism, to exclude boys who had a spontaneous descent before the age of one. There remained an increased risk for the offspring of maternal gardeners and farmers however the confidence intervals widened.

Although these results account for only a small proportion of cryptorchidism cases in Denmark, the authors indicate that their findings have substantiated earlier reports of increased risk of urogenital malformations among boys with possible exposure to pesticides in utero. The lack of direct measurements of exposure has limited the findings of this study. These women were only potentially exposed to pesticides and it is possible that other factors were at play. Additional research that provided more precise exposure measurements would help to more fully investigate the association between maternal pesticide exposure and cryptorchidism in male offspring.