Researchers at Rotterdam’s Erasmus teaching hospital have been working out when is the best age for couples to start having children, and say 23 is the best age for a woman to become a mother if she aims for a family of three.

The international research has just been published in academic journal Human Reproduction and uses computer modelling to determine the best success rates, depending on desired family size.

‘Couples are waiting longer to start a family and many people would like to know what their chances are so they can better plan their education and career,’ research leader Dik Habbema said in Thursday’s Volkskrant.

The research shows couples who want to be 90% sure of having at least three children, should aim for their first child when the woman is 23. ‘If they want fewer children, they can start a lot later,’ Habbema said.

Fertility peak

The many couples who start having children at a later age and go on to have at least three children are lucky, he said. ‘They are on the right side of their fertility peak when they start, but you don’t know that in advance.’

The research shows just 50% of women who wait until they are 41 to get pregnant will be able to have a child without medical intervention. In addition, just 50% of women who start a family at the age of 35 will be able to have three children naturally. For two children, the latest starting age is 31.

The average age a Dutch woman gives birth for the first time is around 29, according to figures from the national statistics office CBS.