Women who wait until their mid-to-late 30s to have a baby are significantly less likely to fall pregnant naturally, an international fertility expert has warned.

According to Dr Louis Keith, professor emeritus of obstetrics and gynaecology at Northwestern University in Chicago, women waiting to have babies is now a global issue'.

"From Sri Lanka to Ireland to the US, age is a worldwide issue. The longer you wait, the more chance you will require help to have a baby," he told Irishhealth.com.

He noted that the situation 20 years ago was ‘very different', with women more likely to have babies at a younger age.

Dr Keith, who has worked as an obstetrician and gynaecologist since the 1960s, insisted that despite the problems associated with waiting to have children, ‘it is a woman's right to decide when she is ready'.

However, he emphasised that women who are 35 or older will face more problems, as their ability to ovulate and the number of eggs they have naturally decline.

"At this age, time is running out and it will become more difficult to conceive naturally," he warned.

He added that while there are no specific risks associated with men who wait to have children, ‘as men age, their ability and desire to have sex may decline', which could affect the chances of conception.

Dr Keith was in Dublin to discuss the issues of conception, pregnancy and fertility.

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