Background: Epidemiologic studies have reported associations between air pollution levels and semen characteristics, which might in turn affect a couple’s ability to achieve a live birth. Our aim was to characterize short-term effects of atmospheric pollutants on fecundability (the month-specific probability of pregnancy among noncontracepting couples).
Methods: For a cohort of births between 1994 and 1999 in Teplice (Czech Republic), we averaged fine particulate matter (PM2.5), carcinogenic polycyclic aromatic hydrocarbons, ozone, nitrogen dioxide (NO2), and sulfur dioxide levels estimated from a central measurement site over the 60-day period before the end of the first month of unprotected intercourse. We estimated changes in the probability of occurrence of a pregnancy during the first month of unprotected intercourse associated with exposure, using binomial regression and adjusting for maternal behaviors and time trends.
Results: Among the 1,916 recruited couples, 486 (25%) conceived during the first month of unprotected intercourse. Each increase of 10 µg/m3 in PM2.5 levels was associated with an adjusted decrease in fecundability of 22% (95% confidence interval = 6%–35%). NO2 levels were also associated with decreased fecundability. There was no evidence of adverse effects with the other pollutants considered. Biases related to pregnancy planning or temporal trends in air pollution were unlikely to explain the observed associations.
Conclusions: In this polluted area, we highlighted short-term decreases in a couple’s ability to conceive in association with PM2.5 and NO2 levels assessed in a central monitoring station.
From the aInserm, Institut Albert Bonniot (U823), Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, Grenoble, France; bGrenoble University, Institut Albert Bonniot, Grenoble, France; and cLaboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR, Prague, Czech Republic.
The Teplice program was supported by grants from the European Union. The Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health was supported by an AVENIR/ATIP grant from Inserm. The authors have no potential conflict of interest.
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Correspondence: Rémy Slama, Inserm, Institut Albert Bonniot (U823), Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, F-38042 Grenoble CEDEX 09, France. E-mail: firstname.lastname@example.org.
Received November 26, 2012
Accepted May 26, 2013