Men whose fathers smoked at the time of pregnancy had half as many sperm as men whose fathers did not smoke, according to findings recently published in PLoS One.
A second study, in Advances in Nutrition, found certain supplements provided a beneficial effect on sperm.
“Since paternal and maternal tobacco smoking often coincide, it is difficult to discriminate whether effects are mediated paternally or maternally when using questionnaire- or register-based studies. Therefore, getting an objective measure of the maternal nicotine exposure level during pregnancy might help disentangling the impact of paternally and maternally derived exposure,” Jonatan Axelsson, specialist physician in occupational and environmental medicine at Lund University in Sweden, and colleagues wrote in the first study.
Researchers obtained semen samples, paternal smoking history and maternal semen samples from 104 men living in Sweden aged 17 to 20 years.
Researchers obtained semen samples, paternal smoking history and maternal serum samples from 104 men living in Sweden aged 17 to 20 years.
Axelsson and colleagues found the men whose fathers smoked had 51% (P = .003) lower total sperm count than the men whose fathers did not smoke. Further, men whose fathers smoked had 41% (P = .02) lower sperm concentration.
Axelsson told Healio Family Medicine the findings, when combined with other research, may provide the impetus for men who smoke to quit.
“Other studies have also indicated that paternal smoking has been associated with shorter reproductive lifespans in daughters and some childhood cancers,” he said. “Men who might become fathers [should] start a smoke-free life.”
Dietary supplements’ impact
In the second study, Albert Salas-Huetos, PhD, of the urology, andrology and IVF unit at the University of Utah and colleagues wrote that “data strongly suggest a significant decline in male reproductive health, with crucial implications for human reproduction and perpetuation of the species. Research aimed at revealing the causes and implications of this decline is therefore urgently needed.”
Researchers analyzed 28 studies involving 2,900 men aged 18 to 52 years to ascertain the impact of certain supplements on sperm.
They analyzed 28 studies involving 2,900 men aged 18 to 52 years to ascertain the impact of certain supplements on sperm. Findings included:
- 5 mg of folic acid supplements daily in healthy but subfertile patients improved sperm morphology;
- 0.72 g of docosahexaenoic acid and 1.12 g daily of eicosapentaenoic acid significantly improved total sperm count and concentration, sperm motility and morphology;
- 66 to 500 mg of zinc daily for 3 to 6 months improved sperm motility and concentration;
- 200 to 300 mg of CoQ10 daily for 3 to 6 months improved morphology, sperm concentration and total motility and sperm count; and
- 100 µg of selenium daily for 3 months improved sperm motility and increased chances of conception.
Despite the findings, Salas-Huetos cautioned it is premature to suggest supplements are a viable treatment option for the 15% of the worldwide population that is infertile.
“More randomized clinical trials with larger samples and clear inclusion/exclusion criteria are needed in future to test how these types of supplements affect not only sperm parameters but also fecundability. For these reasons, we cannot do any strong recommendation to the general population or primary care physicians,” he said in an interview. – by Janel Miller
Disclosures : Healio Family Medicine was unable to determine authors’ relevant financial disclosures prior to publication.