Having children ages women's DNA by 11 years, new research suggests.
Giving birth shortens women's telomeres by around 4.2 per cent, a study found.
Telomeres ‘cap’ the end of DNA strands, with longer lengths being associated with slower aging, longer lifespans and improved overall health.
Such an extent of telomere shortening is greater than the effects of smoking or obesity demonstrated in previous studies.
Study author Dr Anna Pollack from George Mason University, Virginia, said: 'We were surprised to find such a striking result. It is equivalent to around 11 years of accelerated cellular ageing.'
Researchers believe this may be due to the stress of raising children, particularly in countries without mandatory maternity leave, such as the US.
They stress, however, more research into the link between motherhood and genetic ageing is required, with Dr Pollack adding: 'We’re not saying "don’t have children".
Having children ages women's DNA by 11 years, new research suggests (stock)
Bicarbonate of soda helps women avoid Caesarean-sections, research suggested in January 2017.
When dissolved in water, the kitchen staple enables between 17 and 20 per cent of women having slow or difficult labours to give birth naturally, without harming their babies, a study found.
Speaking on the BBC's Today show, study author Professor Susan Wray from the University of Liverpool explained bicarb neutralises acids in the uterus, which increases women's likelihood of giving birth vaginally.
The bicarbonate used is the standard type available in supermarkets.
Around one-in-four births in the UK and one-in-three in the US are carried out via c-section.
Although usually safe, the procedure can cause blood clots, excessive bleeding and womb infections.
The researchers, which included scientists