Male Reproductive Problems May Contribute To Falling Fertility Rates

Reduced male fertility may be making it even harder for couples to conceive and be contributing to low birth rates in many countries, reveals a new European Science Foundation (ESF) report launched last week at the IPSEN meeting in Paris.

More than 10% of couples worldwide are infertile, contributing to the growing demand for assisted reproduction techniques such as in vitro fertilisation (IVF) for which Robert G. Edwards won the Nobel Prize in Medicine last month.

Sperm counts have dropped significantly in the last 50 years in developed countries. Today, at least one in five 18-25 year old men in Europe have semen quality in the subfertile range. Testosterone levels are also declining. This is mirrored by increasing testicular cancer in most industrialised countries and more developmental abnormalities such as undescended testes. All of these factors are linked to reduced fertility and may have common origins during foetal development.

"The important impact of men's reproductive health on a couple's fertility is often overlooked," said Professor Niels Skakkebæk from the University of Copenhagen, who co-authored the report. "Women postponing motherhood have reduced fertility, and we now see that poor sperm may be making it even harder to conceive. While poor sperm may be part of the reason more couples are using IVF it may also be making those therapies less successful."

Skakkebæk continues: "We need a common strategy in Europe to target research so we can address the poor state of men's reproductive health. That this decrease in male reproductive health has occurred in just a few decades suggests it's caused by environmental and lifestyle factors rather than genetics. So it is preventable if we correctly identify the causes."

In men some lifestyle factors such as obesity and smoking can affect sperm counts, but the effects are small. In contrast, if women smoke heavily in pregnancy, a much larger fall in sperm count is likely in their sons when they grow up. Testosterone levels naturally drop as men age, which may predispose men to cardiovascular and metabolic health problems that pose large financial and healthcare issues for national governments. Low sperm counts and low testosterone levels are both associated with increased risk of early death for men.

Red Meat May Hinder Fatherhood

A diet rich in steak and other red meat might hinder a man's chances of
conceiving a child, say Spanish researchers. According to their study
published in the journal 'Fertility and Sterility', a healthy
antioxidant-rich diet might be the key to sperm quality and motility. Men
who eat a lot of fruit and vegetables, in particular peppers, spinach and
citrus fruits, have higher quality and faster swimming sperm.
'A healthy diet is not only a good way of avoiding illness, but improves
the quality of semen' said Professor Jaime Mendiola, the leading researcher.
'We saw that, among couples with fertility problems coming to the
[fertility] clinics, men with good semen quality ate more vegetables and
fruit, which means more vitamins, folic acid and fibre, and fewer proteins
and fats.'
The study, undertaken at the University of Murcia in Spain, was prompted
by the gradual decline in sperm counts across Europe in the last few
decades. Male patients at two Spanish fertility clinics took part, and
scientists concentrated on the possibility that exposure to contaminants in
the workplace and diet might be reducing chances of successful conception.
They hypothesised that antioxidants could potentially improve sperm
concentration and motility by reducing or slowing the oxidation of other
molecules which harms sperm.
Sixty-one men with fertility problems were enrolled into the study, 30
of whom had problems specifically with sperm count. Interviews with the
participants showed that those with good sperm quality ate significantly
more fruit and vegetables than those whose diets were rich in meat and
full-fat dairy products.'People who eat more fruits and vegetables are ingesting more
antioxidants, and this is the important point' said Professor Mendiola. In
his next study, he will investigate whether there is a difference in sperm
count between men who get their antioxidants via food or from vitamin
supplements.