Sperm donors from men in their early to mid-40s increase a woman’s chance of pregnancy slightly, according to a new study that compared sperm quality of men in their 40s to men in their 20s or younger. The Newcastle Fertility Center's study to be presented at the Annual Meeting of the European Society of Human Reproduction and Embryology (ESHRE) in Germany tomorrow will question current UK guidelines that suggest men over 40 years old should not be accepted as sperm donors.

“Our study shows that we are good at selecting the right sperm donors with the right sperm quality – and that’s why we found no difference in live birth rate despite the increasing age of sperm donors,” said Dr. Meenakshi Choudhary, the study’s lead researcher from the Newcastle Fertility Centre at Life.

Researchers looked at 40,000 cycles of treatment that involved donor sperm between 1991 and 2012 from a database in UK fertility watchdog, the Human Fertilization and Embryology Authority (HFEA). Sperm donors who were between 40 to 45 years old had a 30.4 percent success rate compared to their 20-years-and-younger male counterparts, who had a 28.3 percent successful pregnancy rate using in vitro fertilization techniques.

Older donors also had the advantage with insemination techniques. The birth rate for donors 20 and younger was 9.7 percent, while donors 41 to 45 years old had a 12 percent successful birth rate.

‘The study shows success rates from donor sperm up to the age of 45 are unaffected by age, but it does not answer the question about the health of the children,” said Dr. Allan Pacey, a professor and chair of the British Fertility Society, who added that disorders connected to older sperm donors were “very small but detectable.”

Choudhary added that it’s really the quality of sperm that they’re focusing on and have found that age isn’t as much as a factor as they previously thought. This is the first study major study to investigate the effect of male age on fertility treatment.

“I think I would be worried about raising the age limit for sperm donors to 45 because of the possible effects on the health of children,” Pacey said.

Previously, scientific evidence has been shown that the sperm from older men is more likely to give birth to a child that develops autism or schizophrenia. The older age could account for 20 to 30 percent of neurological disorders and proves that a mother’s age is not the only one to take into consideration. The number of paternal gene mutations increases steadily by two mutations for every year older the father becomes.

“Advanced paternal age has also been associated with long-term disorders in offspring. But the available evidence is limited,” Choudhary said. “It’s sperm quality rather than male age that matters.”

Source: Choudhary M, Ghuman N, et al. Annual Meeting of the European Society of Human Reproduction and Embryology. 2014.