Women who have children after the age of 30 face a greater risk of their offspring developing cancer, scientists have discovered.
Those who were over 35 were more likely to have infants linked to an increased risk of leukaemia diagnoses – especially acute lymphoblastic leukemia (ALL) – as well as non-Hodgkin lymphoma.
For those between the age of 30 and 34, a link was found for Hodgkin lymphoma.
The association may be due to an increase in chromosomal mutations in older people, say the researchers.
The findings are worrying given that the age at which couples are having babies has been rising in recent years.
'We knew that parental age was a risk factor for childhood cancer,' study author Julia Heck, associate professor at the University of California, Los Angeles (UCLA) School of Public Health told Cure.
Children of older parents have a raised cancer risk due to chromosomal mutations (file photo)
'In most cases, older parents confer greater risk, but in some instances very young (teenage) parents may also have offspring with higher cancer rates. We wanted to explore this relationship in our population-based study.'
The number of women aged over 40 having babies has now overtaken those under 20 for the first time in almost 70 years, past research shows.
The fertility rate among older women has more than trebled since the early 80s.
Experts put the trend down to increasing numbers of women focusing on their careers and the spiralling cost of having children.
Women who leave it late to have children are at a much greater risk of severe complications, experts warn.
Those who become mothers over 44 were more than twice as likely to die or suffer a serious condition than those who gave birth in their 20s, a study found.
They were also more than ten times as likely to end up in intensive