| However, one-fifth saw
a decline in sperm quality. Greening, an obstetrician and
endrocrinologist at Sydney IVF, an Australian company that carries out
assisted reproduction, said the
improvements were "substantial and statistically highly significant."
Daily ejaculation not only boosted sperm quality for most of
the men, it also helped sperm motility -- another big factor in successful
fertilisation -- even though volumes of semen declined, he
said.
Greening presented his findings at a conference in Amsterdam
of the European Society of Human Reproduction and Embryology (ESHRE),
which provided details in a press release.
The research did not investigate whether the improvement in
sperm quality led to better pregnancy rates. But previous work has shown that
sperm that is less damaged and more mobile has a better chance
of leading to a healthy baby.
"These results may mean that men player a greater role in
fertility than previously suspected, and that ejaculatory frequency is important for
improving sperm quality," said Greening.
Why this is so is unclear.
Greening said he suspected that the longer sperm stays in the
testicular ducts, the greater its exposure to rogue oxygen molecules that
damage cells.
His advice to couples would be to have sex, or to ejaculate,
daily in the runup to ovulation or to sperm donation for in-vitro fertilisation
(IVF).
"The optimal number of days of ejaculation might be more or
less seven days, but a week seems manageable and favourable," he said.
"It seems safe to conclude that couples with relatively
normal semen parameters should have sex daily for up to a week before ovulation
date."
Courtesy of
http://asia.news.yahoo.com
|
