By Bonnie James
EXCESSIVE cigarette smoking may have a major role in altering sperm quality, thereby adversely affecting male reproductive health, a study conducted by Qatar University in collaboration with Hamad Medical Corporation has indicated.
Seminal parameters such as sperm concentration, total sperm count and forward motility, and sperm morphology, which refer to the size and shape of the sperm, were changed due to heavy smoking, it was revealed.
The objective of the study was to evaluate any possible abnormalities or deterioration of the sperm head, mid-piece and tail in heavy smokers and non-smokers using both scanning and transmission electron microscopes.
“A significant reduction in seminal volume, sperm concentration and percentage of motile spermatozoa were detected in smokers,” Nahla Afifi, a researcher at QU’s Environmental Studies Center, explains in a paper published in ‘Alrkiat’, the ESC’s bulletin.
Examination through scanning electron microscope indicated a significant increase in the number of head, mid-piece and tail abnormalities in sperm samples from heavy smokers.
Changes in the ultrastructure of the head, mid-piece and arrangement of axonemal microtubules were higher in smokers compared to non-smokers.
The American Council on Science and Health (ACSH) had mentioned in a paper some years ago that sperm malformation may contribute to the occurrence of spontaneous abortion and birth defects.
Afifi has pointed out earlier studies which indicate that cigarette smoking affects reproductive health in both men and women more than the consumption of caffeine or alcohol.
“Recent interest in the effects of smoking on male reproduction has apparently increased as it was reported that sperm counts had dropped by about 50% world wide between 1938 and 1991,” she observed.
There is a growing realisation that male reproductive health could be impaired by a small but increasing number of environmental and occupational exposures.
“Scientists suggest that it may be due to the direct effect of both biological and toxicological reasons on spermatogenesis and the hormones related to it,” Afifi maintains.
According to ACSH it has been documented that cigarette smoke contains 4,000 chemical compounds, including over 60 carcinogens.
Several chemicals found in the semen of cigarette smokers are components of cigarette smoke or are metabolic by-products of such components.
Some of these chemicals — nicotine, for instance — are found at higher concentrations in semen than in blood.
World Health Organisation’s statistics published last year had said that almost 1bn men and 250mn women smoke.
About 35% of men and 22% of women in developed countries and 50% of men and 9% of women in developing countries smoke tobacco.
The rates of tobacco consumption are high when it comes to the Eastern Mediterranean Region with the rates of smoking in most of the countries reaching up to 50% among men and around 10% among women.
“The situation among youth of both sexes is even more serious,” Afifi observes.
The scenario in Yemen and Lebanon is the extreme, with 29% of women in Yemen and 33.7% of youth aged between 15 and 19 in Lebanon using tobacco, adds the researcher.
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