In utero exposures to maternal smoking place men's reproductive health at risk

- Reported, March 4, 2004

 

 

In utero exposures to maternal smoking place men's reproductive health at risk According to a study from Denmark, "between 1996 and 1999, the authors invited all young men from five European countries who were undergoing compulsory medical examination for possible military service to participate in a study on male reproductive health. The participation rate was 19% in two cities in Denmark (n=889), 17% in Oslo, Norway (n=221), 13% in Turku, Finland (n=313), 14% in Kaunas, Lithuania (n=157), and 19% in Tartu, Estonia (n=190). Each man provided a semen sample, was examined by a physician, and, in collaboration with his mother, completed a questionnaire about general and reproductive health, current smoking habits, and exposure to smoking in utero."

"After adjustment for confounding factors, men exposed to smoking in utero had a reduction in sperm concentration of 20.1% (95% confidence interval (CI): 6.8, 33.5) and a reduction in total sperm count of 24.5% (95% CI: 9.5, 39.5) in comparison with unexposed men," reported T.K. Jensen and colleagues, University Copenhagen, Rigshospital.
 

"Percentages of motile and morphologically normal sperm cells were 1.85 (95% CI: 0.46, 3.23) and 0.64 (95% CI: -0.02, 1.30) percentage points lower, respectively, among men exposed in utero, and exposed men had a 1.15-ml (95% CI: 0.66, 1.64) smaller testis size. The associations were present when data from the study centers were analyzed separately (though not in Lithuania, where only 1% of mothers smoked during pregnancy), although the strength of the association varied."

"Maternal smoking may have long-term implications for the reproductive health of the offspring. This is another good reason to advise pregnant women to avoid smoking," researchers concluded.

Jensen and colleagues published the results of their research in American Journal of Epidemiology (Association of in utero exposure to maternal smoking with reduced semen quality and testis size in adulthood: A cross-sectional study of 1,770 young men from the general population in five European countries. Am J Epidemiol, 2004;159(1):49-58).

For additional information, contact T.K. Jensen, University Copenhagen, Rigshosp, Department Growth & Reproductive, GR 5064, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.

The publisher of the American Journal of Epidemiology can be contacted at: Oxford University Press Inc., Journals Department, 2001 Evans Rd., Cary, NC 27513, USA.