June 30, 2009
Daily Sex Increases Sperm Quality, Odds Of Pregnancy
Having sex on a daily basis improves sperm quality in men, which can enhance their chances of conceiving a child, researchers reported on Tuesday.
Dr David Greening of Sydney IVF headed the new study of 118 men to show that daily ejaculation for seven days improves their sperm quality by reducing the amount of DNA damage.
Greening presented his findings to the 25th annual meeting of the European Society of Human Reproduction and Embryology in Amsterdam.
Prior to the study, researchers had debated whether or not it was necessary for men to abstain from ejaculation for a few days before attempting to conceive with their partner.
"All that we knew was that intercourse on the day of ovulation offered the highest chance of pregnancy, but we did not know what was the best advice for the period leading up to ovulation or egg retrieval for IVF," said Greening.
"I thought that frequent ejaculation might be a physiological mechanism to improve sperm DNA damage, while maintaining semen levels within the normal, fertile range."
Greening studied 118 men with higher than normal sperm DNA damage. Men were instructed to ejaculate each day for seven consecutive days.
Before the study began, the men's sperm had DNA damage ranging between 15 percent and 98 percent, based on the DNA fragmentation index.
On the seventh day of the study, Greening found that 96 men, or 81 percent, had an average 12 percent decrease in their sperm DNA damage. Meanwhile, 22 men, or 19 percent, had an average increase in damage of nearly 10 percent.
"Although the mean average was 26 percent which is in the 'fair' range for sperm quality, this included 18 percent of men whose sperm DNA damage increased as well as those whose DNA damage decreased. Amongst the men whose damage decreased, their average dropped by 12 percent to just under 23 percent DFI, which puts them in the 'good' range. Also, more men moved into the 'good' range and out of the 'poor' or 'fair' range. These changes were substantial and statistically highly significant," said Greening.
"In addition, we found that although frequent ejaculation decreased semen volume and sperm concentrations, it did not compromise sperm motility and, in fact, this rose slightly but significantly."
"Further research is required to see whether the improvement in these men's sperm quality translates into better pregnancy rates, but other, previous studies have shown the relationship between sperm DNA damage and pregnancy rates," Greening concluded.
"The optimal number of days of ejaculation might be more or less than seven days, but a week appears manageable and favorable."
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