Around three babies are born to women over 50 every week, more than double the number five years ago, according to latest figures.
There were 154 babies born to mothers in their 50s in 2012, a rise of a third in a year, the Daily Mail said in a report.
The figure was more than double the 69 births to over-50s in 2008, and around three-and-a-half times the 44 babies born to the over-50s in 2000.
The steep increase in the number of older mothers was revealed by health ministers in response to a parliamentary question, the Mail said.
Health experts warned that having a baby when you are older increases the chances of complications, with a greater chance of miscarriage and the development of genetic abnormalities with the child.
There is also extra pressure on the NHS because of the need for increased care for older mothers and their children.
More women are also having children when they are over 40, the Mail said − 29,994 in 2012 compared with 26,419 in 2008, a rise of 13% − with one of 25 becoming mothers in their 40s.
Around 20% of babies are born to mothers of 35 and over, the highest proportion since 1938, while the numbers of women having children when they are under 25 has plummeted, down to 23% in 2012 from around 50% in the early 1970s.
“Older mothers are more likely to have increased rates of miscarriage and ectopic pregnancies”
Louise Silverton, director for midwifery at the Royal College of Midwives, highlighted that the increasing number of older women having babies tended to have more complications than younger mothers.
She said: “This is more pronounced as women have babies at increasingly greater ages.
“Older mothers are more likely to have increased rates of miscarriage and ectopic pregnancies and genetic problems in the child and other issues such high blood pressure, diabetes and problems with the placenta,” Ms Silverton told the Mail..
She warned that greater numbers of midwives were needed to cope with more women delaying motherhood.
Advances in fertility treatment have allowed women to delay having children.