14 DAY TRIAL // Even in these modern days, when the lifespan of humans surpasses an all time record, women over 40 are generally believed too old to have babies, yet somehow there is no mention of the limit age men become less fertile at. If 40 looked like a rather young age to stop having children, a new study now shows that men older than 35 have significantly less chances of becoming fathers. The study involved 12,200 couples with fertility problems.
Additionally, the fertility rate in men drops even more as they surpass the age of 40, the study says, regardless of whether the conception was natural or done through artificial insemination. This implies that the most likely cause for the effect is the DNA damage of sperm cells.
Between January 2002 and December 2006, more than 12,000 couples visited the Eylau Center for Assisted Reproduction in Paris, in the hope that they would find a solution to their fertility problems. The women underwent intrauterine inseminations since they had no problems with their fertility, while the men's sperm was examined for quality, size, shape and ability to swim, in order to reveal the cause triggering the fertility problems.
While women over 35 appeared to follow the general guideline and had a higher chance of miscarriage and lower pregnancy rate, the real shocker came when the researchers realized that males in their mid 30s or older were most likely to be the cause of miscarriage, compared to the younger men. Also, it seems that the chance of a successful pregnancy drops significantly when the man is more than 40 years old and there's a probability rate of only 10 percent of the treatment resulting in a pregnancy.
"This research has important implications for couples wanting to start a family," said Dr. Stephanie Belloc of the European Society of Human Reproduction and Embryology.
In a conference in Barcelona, Dr. Belloc said that such couples should undergo intrauterine inseminations, although in case of DNA damaged sperm an ICSI technique is indicated.
"These methods, although not in themselves a guarantee of success, may help couples where the man is older to achieve a pregnancy more quickly, and also reduce the risk of miscarriage. There is growing evidence from a number of studies to show that men are not totally immune from reproductive aging," Dr. Belloc added.
"Previous studies of couples trying to conceive naturally or undergoing IVF have shown that men over the age of about 40 are less fertile than younger men. Moreover, if they do achieve a pregnancy their partners are more likely to miscarry. This study reinforces the message that men aren't excused from reproductive aging," said Dr. Allan Pacey of the Sheffield University.