Fertility declines after 35, researchers remind women

A leading reproductive biologist has warned against delaying motherhood beyond 35 years old, highlighting the risks of age-related infertility.

Mary Herbert, professor of reproductive biology at the Institute for Ageing and Health, Newcastle University, has said that she fears not enough people understand that female fertility begins to decline more rapidly during the mid-30s.

'What we can say for sure is that reproductive technologies do not do much to buy time', she told an audience at the British Science Festival in Newcastle. 'Perhaps the most important message to give is that the best cure of all is to have your babies before this clock strikes 12'.

Recent figures show that the percentage of mothers giving birth for the first time between 35 and 39-years-old had risen from 6.8 percent in 1986 to 17 percent in 2008, the Independent reported. The researchers from Newcastle University suggested the rise was down to women placing priority on career-climbing and saving money, ahead of starting a family.

'From talking to young women, it's about getting my career established, but in a sense I find that misguided because there is no career that gets less busy as you go on', Professor Herbert said. The cost of childcare is also seen as a deterrent factor in having children.

The UK's Science Media Centre called a public press conference ahead of the British Science Festival, at which Professor Herbert and colleagues spoke about their concern that the public health message about ageing eggs is not getting through to women, at a time when the number of over 40s attending fertility clinics is reportedly increasing.

Some people were unaware of the risks of having children in later life, such as an increased risk factor for stillbirth and Down's syndrome, and that being able to conceive can become more difficult, the researchers said.

Professor Herbert said women 'should think of family planning not just in the context of preventing pregnancy but also think of it in the context of having your babies at a time when you still have your reproductive fitness'.

Judith Rankin, professor of maternal and perinatal epidemiology at Newcastle University, also spoke at the event. 'From a public health perspective, when we look at the whole population, [the] message has to be that if you're 35 or over, your likelihood of pregnancy is greatly reduced', she said.

'I think it's better to think about it [in your 20s], and have that thought process informed by all possibilities, she added.

Natika Halil of the Family Planning Association, said: 'Conversations about planning a family are important as is accurate information about contraceptive choice'. However, Halil added that, 'women are mindful of their fertility and any discussion should be done without scaremongering'.

'Fertility doesn't disappear after 35 and doesn't stop overnight', she said.