Toyboys a bonus for late motherhood
Older women who want to start a family may be better off taking a younger lover, claim fertility researchers
More mature women who want to start a family should find themselves a toyboy, research suggests. A fertility treatment study found that women with younger lovers fared far better than those with partners of the same age or older. Experts who examined 20,000 cycles of fertility treatment said sperm from younger men appeared to “invigorate” eggs from older women, who were less likely to conceive when paired with a man of their own age.
‘The eggs are in a way invigorated by the sperm of younger men’
WOMEN should find themselves a toy boy if they want to start a family, research suggests.
A study of almost 20,000 cycles of fertility treatment found that women with younger lovers fared far better than those with partners of the same age or older.
Experts said sperm from younger men appeared to “invigorate” eggs from older women, who were less likely to conceive when paired with those their own age.
It has long been known that female fertility declines with age, but the situation is less clear with men. Charlie Chaplin fathered a child at 73, while Robert De Niro and Pablo Picasso did so at 68 and Clint Eastwood had his seventh child at 67.
The findings, presented at the European Society of Human Reproduction and Embryology (ESHRE) in Geneva, Switzerland, showed that female age still had the biggest impact on live birth rates. But for younger women, the age of men was a significant factor.
The study, led by Harvard Medical School, tracked live birth rates among couples undergoing fertility treatment between 2000 and 2014.
Women aged 35 to 40 had significant benefits from having a male partner below the age of 30, the study found. There was a 30 per cent relative improvement in cumulative incidence of live birth, compared with those paired with partners the same age.
The women with younger lovers had success rates of 70 per cent, compared with 54 per cent when partners were in the same age bracket.
Cumulative live birth rate refers to the chances of a live birth after one or more cycles of IVF treatment. And women under 30 with male partners aged 40 to 42 were 46 per cent less likely to have a child than those with partners aged 30 to 35.
The effect lessened as women got older and for those over 40, the age of the male partner made no difference to the chances of success – showing the dominant detrimental effect of female age and decreasing egg quality. Previous research has shown that for natural conceptions, increasing male age is associated with reduced pregnancy rates, greater time to pregnancy, and a higher risk of miscarriage. While women are born with their full complement of eggs, men continue to generate sperm as they age, with a rising risk of genetic errors that can affect fertility. Dr Gillian Lockwood, a fertility expert and an executive director of fertility clinic company IVI UK, said: “The age of the woman is a critical factor but this shows you can overcome this to some extent with a younger man. It seems that the older eggs are in a way invigorated by the sperm of younger men.” Dr Allan Pacey, professor of andrology at Sheffield University, said: “We’ve known there are risks from older fathers, with increased risks of autism and schizophrenia, and that is why we have a cutoff for sperm donors. “But this is going beyond that, suggesting there are advantages to bagging yourself a younger man, a toy boy. “I don’t think there is any suggestion here that the younger the better, but it is certainly showing women gain some advantages from having a partner who is younger than them.”
Dr Laura Dodge, the lead researcher from Beth Israel Deaconess Medical Centre in Boston, said: “Our study found an independent effect of male age on the cumulative incidence of live birth. Where we see significant decreases in the cumulative incidence of live birth is among women with male partners in the older age bands.” The scientists analysed data on 7,753 couples seen at a Boston fertility clinic between 2000 and 2014.
Dr Dodge said there was little that men could do to counteract the effect of age on their sperm.
“Most preconception advice for men focuses on semen quality, though studies suggest that this likely cannot fully ameliorate the effects of male reproductive ageing,” she said. “So in the absence of clear evidence of the mechanisms, the best preconception advice we can offer is to maintain a healthy lifestyle.”
Nick Macklon, professor of obstetrics and gynaecology from the University of Southampton, said the findings from the study might encourage both men and women “to get a move on”.
“This information provides new insights and reminds us that it takes two to tango. It’s not just down to the age of the woman,” he said.