Age is no bar to being a good mother and there is no reasonto prevent pensioners from becoming parents, researchers have found.
Women in their 50s and 60s who conceive after fertility treatment are just as capable of being good parents as women in their 30s and 40s, a study has shown.
The finding will bring hope to thousands of women who have delayed parenthood and seek help late in life to have a family.
Even though they run greater risks of complications during pregnancy and childbirth, once their children are born they are just as good at raising them.
It will also give a boost to research into egg freezing, which could allow career women in their 20s to store their eggs for future use in their 40s or 50s or even later.
If egg freezing becomes a practical possibility for the average woman it could fuel a boom in demand for fertility treatment from 40 and 50 year olds.
Researchers from the University of Southern California studied the mental and physical health of 150 women, a third of whom had become parents in their 50s after in-vitro fertilisation (IVF) with donor eggs.
They found there was no significant difference in the health or stress levels of the older women, compared with younger groups in their 40s and 30s, likely to reduce their parenting capacity.
All the women gave birth between 1992 and 2004 at the Women and Children's hospital in Los Angeles and were sent questionnaires, of which half were returned. On mental functioning, the over-50s were the only group who scored significantly higher than the national average.
The finding goes some way to answering critics, who have accused women who seek fertility treatment in their 50s and 60s of being selfish and ignoring the welfare of their children.
But the study was criticised by a British specialist who said it followed women with children up to the age of 12 and did not show how older mothers would cope in their 60s and 70s when their children reached the more challenging teenage years.
Patricia Rashbrook, from Lewes, east Sussex, who became Britain's oldest mother at the age of 62 last July, defended herself against charges that she would be 80 before her child left school by saying it was the "quality of parenting that matters, not age." The study lends support to her case.
Anne Steiner, who led the research to be presented to the American Society for Reproductive Medicine in New Orleans tomorrow, said: "The conclusion from this study, though it is limited and of small size, is that if we look from the perspective of stress and physical and mental functioning, it doesn't seem we can restrict parenting based on these reasons."
All the children in the study were "young kids" with the oldest aged 10 to 12. "[The study] tells us about the relationship between parents and young children but it can't tell us anything about what might happen when they become teenagers. But there is reason to say, in the absence of other data, that maybe we shouldn't jump to the conclusion that it's wrong for women to become mothers at this age."
Bill Ledger, professor of obstetrics at the University of Sheffield, said: "The problem I have is not what happens to mothers at 50 to 55. What worries me is what happens when their children are 18 and they are in their 70s and 80s. I am not in favour of banning things but I am concerned for the welfare of a child whose parents are as old as its peers' grandparents."
In Britain, there is no official upper age limit for fertility treatment but most IVF clinics decline to treat women over 45 because of the increased risks of pregnancy. For NHS treatment the age limit is 39 and many clinics impose lower limits.
However, latest official figures show more than 20 babies a year are born to women over 50 after private treatment at private British fertility clinics.
Patricia Rashbrook, a child psychiatrist, travelled to Eastern Europe for treatment by Professor Severino Antinori, the Italian fertility specialist who has courted controversy by pushing the age boundaries of motherhood.
The interim head of the UK Human Fertilisation and Embryology Authority, Lord Harries of Pentregarth, has given his support to would-be mothers in their 50s and 60s saying they should not be banned from becoming parents.Reuse content