Maternal medication and herbal use and risk for hypospadias: data from the National Birth Defects Prevention Study, 1997-2007

Pharmacoepidemiol Drug Saf. 2013 Jul;22(7):783-93. doi: 10.1002/pds.3448. Epub 2013 Apr 26.


Purpose: To investigate associations between maternal use of common medications and herbals during early pregnancy and risk for hypospadias in male infants.

Methods: We used data from the National Birth Defects Prevention Study, a multi-site, population-based, case-control study. We analyzed data from 1537 infants with second-degree or third-degree isolated hypospadias and 4314 live-born male control infants without major birth defects, with estimated dates of delivery from 1997 to 2007. Exposure was reported use of prescription or over-the-counter medications or herbal products, from 1 month before to 4 months after conception. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, adjusting for maternal age, race/ethnicity, education, pre-pregnancy body mass index, previous live births, maternal subfertility, study site, and year.

Results: We assessed 64 medication and 24 herbal components. Maternal uses of most components were not associated with an increased risk of hypospadias. A new associations was observed for venlafaxine (aOR 2.4; 95%CI 1.0, 6.0) [Correction made here after initial online publication.]. The previously reported association for clomiphene citrate was confirmed (aOR 1.9; 95%CI 1.2, 3.0). Numbers were relatively small for exposure to other specific patterns of fertility agents, but elevated aORs were observed for the most common of them.

Conclusions: Overall, findings were reassuring that hypospadias is not associated with most medication components examined in this analysis. New associations will need to be confirmed in other studies. Increased risks for hypospadias associated with various fertility agents raise the possibility of confounding by underlying subfertility.

Keywords: birth defects; drug safety; herbal; hypospadias; medication; pharmacoepidemiology; pregnancy.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Case-Control Studies
  • Databases, Factual / statistics & numerical data*
  • Drug Prescriptions / statistics & numerical data
  • Drug Utilization Review / statistics & numerical data
  • Female
  • Fertility Agents / adverse effects
  • Humans
  • Hypospadias / chemically induced*
  • Hypospadias / epidemiology
  • Logistic Models
  • Male
  • Multivariate Analysis
  • Nonprescription Drugs / adverse effects*
  • Odds Ratio
  • Pharmacoepidemiology
  • Pharmacovigilance
  • Phytotherapy / statistics & numerical data*
  • Plant Preparations / adverse effects*
  • Pregnancy
  • Prenatal Exposure Delayed Effects*
  • Prescription Drugs / adverse effects*
  • Risk Assessment
  • Risk Factors
  • Selective Serotonin Reuptake Inhibitors / adverse effects
  • United States / epidemiology


  • Fertility Agents
  • Nonprescription Drugs
  • Plant Preparations
  • Prescription Drugs
  • Serotonin Uptake Inhibitors