Women warned of biological clock
13 September 2013 09:45
A women's chances of getting pregnant and having a healthy baby are reduced once their hit their mid-30s
Women planning to have a family have been urged not to delay it into their mid-30s.
Professor Mary Herbert, from the Institute for Ageing and Health at the University of Newcastle, said women should ideally have children before they are 35, as that is when the "clock strikes 12".
Prof Herbert, one of the country's leading experts in reproductive ageing, said when a woman hits her mid-30s, her eggs suffer natural chromosomal damage which fertility treatment cannot overcome.
Speaking at the British Science Festival alongside other fertility experts, she said: "What we can say for sure is that reproductive technologies do not do much to buy time.
"Perhaps the most important message to give is that the best cure of all is to have your babies before this clock strikes 12. I would be getting worried about my daughter if she hadn't had a child by 35."
When a woman is born, she has about two million eggs in her ovaries. These decrease over time, and as the woman gets older, the quality of her eggs is also reduced.
Damage to chromosomes - the DNA that contains genes - can result in infertility, stillbirth, or birth defects such as Down's syndrome.
Many women see freezing eggs as an option to ensure pregnancy when they are ready for it, but the experts warn even this process cannot guarantee success - and is very expensive.
Figures show that between 1986 and 2008, the average age at which a British woman had children increased from 27 to 29. Over the same period, the proportion of mothers aged 35 to 39 rose from 6.8% to 17%.
But pregnancy at all ages carries risks, and therefore anyone planning to travel while expecting is encouraged to take out
pregnancy travel insurance to help deal with any problems while away from home.
Prof Herbert also said that many women cite their career as a reason to delay pregnancy, but she challenged this idea. "In a sense I think that's misguided, because there's no career where it gets less busy as you go on," she added.
And she suggested the issue is something society as a whole should address, to better understand "what the barriers are to women having their children early".