A recent study shows that smoking during pregnancy and breastfeeding may impair sons’ fertility.
We all know that smoking affects our health causing primary respiratory and cardiovascular problems. In pregnant women cigarette smoke can affect not only mom’s health but also child’s health, causing premature birth, growth retardation, miscarriages, reduced birth weight, and sudden infant death syndrome 1,2,3,4.
The team led by Professor Mc Laughlin at the University of Newcastle (New South Wales, Australia) published a study in Human Reproduction on the effect of maternal smoking using a mouse model 5. They exposed 27 female animals to cigarette smoking before, during, and after pregnancy and analyzed the the pups and the adult male mice. Smoking affected the viability of germ cells, the diameter of seminiferous tubules, and the morphology of neonatal testes in the pups. In the adult mice, germ cells showed DNA damage and Sertoli cell (cells that promote sperm cell development) showed aberrant function; these phenomena were accompanied by alteration in the expression of genes involved in several pathways, including spermatogenesis, oxidative stress, and Sertoli cell function. Furthermore mice from “smoking” mothers had fewer sperm with affected motility and fertilization ability (binding to the zona pellucida of the egg). This work is a comprehensive demonstration in a mouse model that maternal cigarette smoke compromises the fertility of the male offspring. Previous studies suggested the same effects but they were not conclusive.
When a woman gets pregnant, she receives many warnings on what she may or may not do. Some of these warnings are based off common sense, previous observational and epidemiological studies or surveys, and the woman doesn’t really get an explanation of the precise consequences of her acts if she doesn’t follow the instructions—this is not always the case—but all she gets is a warning. In contrast, the consequences of cigarette smoke are known and are not short-term (miscarriage, reduced birth weight, etc.) but long-term consequences. The study described above is an accurate demonstration This study should really be a deterrent for pregnant women who are still smoking, that are around 13–20% in the United States(the reports are controversial) and 4–20% in Europe (depending on the country) 6. Further studies in the future may highlight other long-term damages and may focus on the damages of not only maternal smoke but also secondhand smoke.
1Perinatal complications associated with maternal tobacco use.Andres RL, Day MC. Semin Neonatol. 2000 Aug;5(3):231-41. Review.
2Revisiting the effect of maternal smoking during pregnancy on offspring birthweight: a quasi-experimental sibling analysis in Sweden. Juárez SP, Merlo J. PLoS One. 2013 Apr 17;8(4):e61734.
3Environmental tobacco smoke and risk of spontaneous abortion. George L, Granath F, Johansson AL, Annerén G, Cnattingius S. Epidemiology. 2006 Sep;17(5):500-5.
4Prenatal smoking among adolescents and risk of fetal demise before and during labor.Aliyu MH, Salihu HM, Alio AP, Wilson RE, Chakrabarty S, Clayton HB.J Pediatr Adolesc Gynecol. 2010 Jun;23(3):129-35Epidemiology. 2006 Sep;17(5):500-5.
5Damaging legacy: maternal cigarette smoking has long-term consequences for male offspring fertility.Sobinoff AP, Sutherland JM, Beckett EL, Stanger SJ, Johnson R, Jarnicki AG, McCluskey A, John JC, Hansbro PM, McLaughlin EA.Hum Reprod. 2014 Sep 30. pii: deu235.
6Characteristics of women who continue smoking during pregnancy: a cross-sectional study of pregnant women and new mothers in 15 European countries.Smedberg J, Lupattelli A, Mårdby AC, Nordeng H.BMC Pregnancy Childbirth 2014 Jun 25;14:213.