Women who have children in their mid-twenties live the longest, a study suggests.
Prior research linked becoming a mother in their thirties with longevity, with experts theorising that childbirth might speed up the ageing process.
But now researchers from the University of Seoul in South Korea have claimed the sweet spot may be between 24 or 25 after studying 4,000 women.
They found those who had a baby before or after then had an up to 5 per cent higher risk of dying from any cause within 18 years.
The trend was ‘U’ shaped, meaning the risk was greater the further away from the age of 24 or 25 they were when they gave birth.
Very young mothers tend to be from deprived areas which puts them at higher risk of a host of mental and physical illnesses, the researchers said.
They speculated that the toll of childrearing and childbirth may be tougher for older mothers.
Much like South Korea, both the UK and US have seen the age at which women have their first child steadily increase in recent decades.
South Korean researchers found that women who had their first baby when they were between the age of 24-25 had the least chance of dying over the next 18 years compared to mothers who had children earlier or later in life
What are some of the risks of having a baby later in life?
The number of older mothers has soared in recent decades, as more women concentrate on their career and start families later.
But doctors tend to warn women not to leave it too late to have children. They stress that with age fertility drops and their risk of complications, including stillbirths, increases.
Experts estimate women in their late forties have as little as a one in 20 chance of becoming pregnant because of their lower supply of eggs, which are less capable of being fertilised.
The British Fertility Society previously warned celebrities who have children in their 40s are giving women false hope about late motherhood.
Chairman Adam Balen said celebrities who paraded ‘miracle babies’ will often have used IVF or donor eggs, both of which can cost thousands of pounds.
Because they do not make this public, their fans fail to realise the fertility issues and health problems that may result.
Demand for donor eggs, one of the most common methods for older women to have a baby, have soared in recent years.
Other options include IVF, if the woman still has some of her own eggs, or even intrauterine insemination – when sperm is directly placed into the uterus using a catheter.
Fertility drugs and surgery are two other possibilities.
The average age of a first-time mother in Britain is now 29. In the US, the Center for Disease Control says the average age of a first-time mother was 26 in 2014.
In the latest study, published in the journal Maturitas, scientists looked at data from 4,044 women in two regions of South Korea, Ansan and Anseong.
They compared 1,498 women who gave birth to their first child between the age of 20 and 23, 1,033 mothers who had their first child at 24-25, and 1,513 women who had their firstborn between the ages of 26 and 36.
Researchers then used Government health records to follow up with women 18 years later.
A total of 243 women died over the course of the study, with over half of those in the younger mother demographic and a third in the older.
The researchers analysed deaths from both cardiovascular diseases, like heart attacks and strokes, as well as all causes of death.
They found survival rates for cardiovascular disease was 97.3 per cent for younger mothers, 99.6 per cent for women in their mid-twenties and 98.7 per cent for older mothers 18 years after the birth of their first child.
Looking at all causes of death, survival rates were 91.1 per cent for younger mother, 96.4 per cent for women in their mid-twenties, and 95.2 per cent for older mothers in the 18 year study period.
Professor Sangshin Park, an expert in epidemiology at the University of Seoul, said younger mothers having poorer health outcomes could be due to socio-economic reasons.
‘In general, young people from disadvantaged backgrounds were at higher risk of having children in their teens,’ he said.
He added that previous research had also linked earlier young first-time mothers to an increase chance of obesity and depression both of which are known to impact life expectancy.
In terms of the health impact on older mothers, Professor Park said other research had indicated older women have more trouble recovering from the physical effects of pregnancy.
‘Elderly mothers have more difficulty recovering from pregnancy and childbirth than younger mothers, and their muscles may not be able to function as before’ he said.
He added that older mothers may struggle to exercise and maintain good health while juggling both a career and a child.
‘Busy daily routines could also lead to a lack of exercise and obesity, and working and child-rearing stress may raise mother’s blood pressure,’ he said.
The authors acknowledged that their study has several limitations, one being they only examined data from two regions of South Korea and that further research should look at broader populations.
They also said they were unable to analyse data from first time mothers under the age 20 and over the age of 35 due to the small number of women in these sample sizes.
Additionally, they said Government data did not record the women’s smoking status before their first child meaning this was a factor that could have influenced the results.
Concluding, researchers said more work was needed to further explore whether women’s timing of childbirth poses a risk to their health outcomes and lifespan.
Various reasons have been given for the rise in the average age of first time mothers in the UK and US.
Some have attributed the trend to women wanting to have an established career before having motherhood.
Others have blamed the rising cost of living and property prices on couples are putting off having children until they are older and more financially secure.