Cigarette Smoking
Cigarette smoking has been shown to significantly affect semen
quality. Regular smoking causes a 23% decrease in sperm
density (concentration) and a 13% decrease in motility (when
averages are taken from nine separate studies). To a lesser extent,
smoking causes toxicity to the seminal plasma (the fluid ejaculated
with the sperm). Sperm from non-smokers were adversely affected (had
significantly decreased viability) when placed in the seminal plasma
(hormonal) of smokers.
Smoking affects the hypothalamic-pituitary-gonatropin axis, most
commonly affecting levels of estradiol and estrone (estrogens, which
are hormones found in higher concentrations in women). The Leydig
Cells, which are in the testes and produce testosterone, may have
secretory dysfunction. Most worrisome is that there is evidence that
suggests that paternal smoking may also be associated with
congenital abnormalities and childhood cancer, though the relative
risk in most studies is less than two.Exercise
Moderate amounts of exercise can only be helpful. However,
long-distance runners (men who run more than 100 miles per week) and
distance cyclers (men who ride more than 50 miles per week) have
decreased spermatogenesis. These activities should be moderated when
a sub-fertile man is attempting conception. |
