The perfect age to have a baby (according to data)

baby decade
baby decade

It’s the million-dollar question to which there is no right answer: when is the best time to have a baby? More women are choosing to have children in their late 30s or 40s, or not at all. After years of scaremongering headlines about the mid-30s “fertility cliff”, advances in medical treatment mean later motherhood is an option for many. In England and Wales, there are now twice as many women giving birth over the age of 40 as there are teenage mothers. Overall, birth rates have hit a 20-year low in the UK, mirroring a long-term decline in the number of births across the developed world.

The average age of a first-time mother in the UK reached 30.9 years in 2021. It would not be surprising if it rose further, as would-be mothers must balance the biological imperative of fertility with countless other factors: career prospects, housing, and the fact that many women feel they have been priced out of motherhood (not least because of the crippling cost of childcare).

Financial pressure in particular looms large – one survey from Censuswide earlier this year among adults aged 18-35 found that just under two-thirds of respondents cite finances as the number one factor in delaying or deciding not to have children. A report from the US National Bureau of Economic Research, looking at Danish population data, found that having children creates a 20 per cent gender pay gap for women in the long term. So what is the ‘best’ decade to have a baby?


Although fewer women are choosing to have children in their 20s, those who do have biology on their side. Research shows that women trying to conceive under the age of 30 have an 85 per cent chance of doing so within one year; this declines to 44 per cent by age 40.

It is an inconvenient truth that “the peak of fertility for women is around the mid-20s”, says Cesar Diaz-Garcia, a consultant in reproductive medicine at the London Fertility Clinic in Portland Hospital. “When it comes to fertility with IVF treatments, we start to see worse results after [a woman is in her] mid-30s. The genetic quality of the eggs starts to be compromised, which means they are more likely to carry chromosomal abnormalities.”

Perhaps surprisingly, public opinion is still skewed in favour of mothers in their late 20s, too. A 2021 YouGov survey found that the majority of the public think the “ideal” age for a woman to become a mother is 28, despite this being more than two years younger than the national average; 81 per cent thought that over 46 is “too old” to become a mother, but respondents were more lenient on older fathers.

However, taking time out in your mid to late 20s can have a knock-on effect on your career and long-term income. A landmark Danish study found that younger mothers fare worse financially: women who were 31 or older when they had their first baby had a higher lifetime income than women who had a baby before the age of 31. The study found that having children before the age of 25 had a particularly negative impact, reducing a woman’s lifetime earnings by two years’ worth.

The study was on both college-educated and non-college educated women and found this effect across the board: “both college and non-college women, compared to childless women, are associated with lower income of more than twice their respective average annual income when [having their first child under the age of 25]”.

Data from the Institute of Fiscal Studies shows that 12 years after their first child was born, British women are paid on average 33 per cent less than men of the same age – the logic follows that the earlier you start, the earlier the wages chasm starts to widen.

Lynda Hamilton Parker, 45, from Fife, Scotland, was 20 when she had her first child in April 1999.

“When I fell pregnant, I was actually still a student. I graduated when my daughter was just six months old,” she says. “Your career definitely does take a back seat. There’s no doubt about that. I’ve been freelance for the last 15 years as a writer and publisher; I’ve realised that’s the only way I can get it to work for [my children].”

Initially, Parker struggled financially and had to leave her job as a graduate PR assistant and move home with her parents to care for her daughter. “I just had really little support,” she says. “My parents were very unsupportive of my relationship with my daughter’s father. We split several times and got back together, eventually splitting for good when our daughter was around two.

“I lacked emotional support and felt incredibly lonely. My dad didn’t acknowledge that I was pregnant until I was around six months and really starting to show.

“I suppose I felt embarrassed and slightly ashamed. I later went on to develop post-natal depression. My mum wanted me to pay for her to look after my daughter so that caused arguments and my partner didn’t help out financially. I had very little money of my own and wanted to save for a flat.

“I felt like I couldn’t make my own decisions and was trapped. I ended up at my mum and dad’s until [my daughter] was one. I then rented a series of flats until I could afford to buy my own. I ended up working full-time in retail so I could afford a mortgage. My daughter went to a private nursery.”

“But I obviously have no regrets. The biggest pro for me is that I now have a fantastic friend who is my 24-year-old daughter… we have a really special bond.”

Lynda Hamilton Parker
Lynda Hamilton Parker was 20 when she had her first child in 1999

Polly*, 34, from south London, who had the first of her two children aged 28, agrees. “Now I think that I had a child in my 20s, it does sound very young, but at the time you never see it.

“I feel as though in your mid-20s and onwards, you’re [often] on the cusp of making quite a big jump in your career. When I went on maternity leave for my first child, my friends made really big leaps up to kind of more senior managerial levels… within that period where I’ve gone off and had a child,” she says.

However, she says, what you might lose out on in terms of early career progression you gain in energy to spend time with your children when they are young.

“I’ve got friends who became mothers at different ages – we’re all envious of when the other had a child. Two of my friends had a child in their 40s and 50s: I look at both of them and think, ‘You had your careers established, you have money to be able to enjoy things more.’

“But they say: ‘When I see you with your kids, I’m jealous that you have been so much younger.’

“My friend that had a child in her 50s said she is just so tired, and just doesn’t have the same energy levels and resources that she had when she was younger. Whereas my other friend had a child in her 40s and she had complications in her pregnancy… she found it much harder to get pregnant. She thought that if she tried younger she would’ve been able to get pregnant more quickly and it would have given her more choice.”


There has been a clear shift to more women having their first child in their 30s, and there are good reasons why, including the likelihood of a higher salary, more stable career and a more established relationship.

The average age of first time mothers has been increasing for decades: in 1990, it was 27.7, now it is 30.9. Births to women in their 30s now eclipse every other age group. According to ONS data, in 2021 there were 75,602 babies born to mothers aged 20-24 and 163,223 to those aged 25-29, but 216,738 to mothers aged 30-34 and 124,942 to women aged 35-39.

There is some evidence to suggest that financially, your early 30s are the sweet spot – and the chance of becoming pregnant is still high.

A woman aged 30 has only a slightly lower chance of becoming pregnant than in their late 20s: a 75 per cent chance within one year at age 30 and then a 66 per cent chance at 35. This then drops more rapidly between 35 and 40 as the number of eggs and their quality declines.

New Telegraph Money analysis has found that women having children in their 40s are likely to retire with less in their pensions than younger mothers. It found that a woman who takes a two-year break to have a child at 30 before returning to work part-time at 32 and full-time at 40, will retire with £11,000 more in their pension than a woman who gives birth at 40 while earning £6,000 more.

“The more you can put in early on, the more chance of investment growth over time. There is an argument to say, max out on your pension before you have kids, and then it doesn’t matter so much if you miss out on the later years because you already have loads in,” says Rebecca O’Connor, director of public affairs at online pension provider PensionBee. “If you haven’t done that, then the earlier you have kids the better because you get back to work quicker, you get back into the zone of career progression and salary raises quicker, and you can take advantage of that and shovel it into your pension pot.”

O’Connor, 42, had her first child aged 30, and said “it helped having those [early] years of looking after the children out of the way” in her early 30s.

“My kids still need me, but I can now focus more on my career. Another issue worth thinking about is the support you may need to raise children – if you are counting on grandparents to help look after your kids, then their age makes a difference too… the older you are, the older your parents and parents-in-law are and the harder it is to rely on them for support. So then you’re looking at paid-for childcare.”

Rebecca O’Connor had her first child at 30
Rebecca O’Connor had her first child at 30

Psychotherapist Anna Mathur, author of Mind Over Mother: Every mum’s guide to worry and anxiety in the first years, says the 30s are seen as a good decade to have children simply because it is likely your peers will be doing it then.

“Socially, I think a lot of people tend to have babies around the same time as their friends,” she says.

There are many valid reasons why women might delay motherhood, including “wanting to establish your career, seeing people in your workplace go on maternity leave and then not come back in the way they hoped or expected to”, she adds. “When you have children it can really adjust what your priorities are – you can think, ‘I’m fearful of this impacting my career’, but then when you have a baby your priorities shift.”


The number of women becoming first-time mothers in their 40s has increased in recent years: one in 25 births in the UK is to a woman aged 40-plus.

Data from the Centers for Disease Control and Prevention (CDC) in America shows that while birth rates for women under 40 are in decline, those for women in their early 40s have increased by three per cent every year since 1982.

The birth rate for those aged 45-49 also rose three per cent between 2017 and 2018.

Emma Rose, 42, from Somerset, has no regrets about waiting until she was 40 to have her first child. She got married in 2015 and her son was born in 2021. “I wanted to feel like I’d done what I wanted before I had a child – I got to travel quite a lot as part of my job; I never wanted to feel like I would resent having the child,” she says. “And there’s being able to buy a house, and making sure we were settled from that point of view. A lot of our friends have children who are in senior school or finishing GCSEs. [But] from a personal life perspective, I have no regrets about having had him later.”

Emma Rose has no regrets about waiting until she was 40 to have her first child
Emma Rose has no regrets about waiting until she was 40 to have her first child

The downside, of course, is that the chance of conceiving naturally is significantly lower in your 40s than the decade prior: some experts put the chance of becoming pregnant naturally in your 40s at 5 per cent each month.

The British Fertility Society says the maximum age a woman should start trying for a baby, if they want to be 90 per cent certain they will have at least one child without IVF, is 32 – although this does not make having a child in your 40s an impossibility by any means.


In 2021, Naomi Campbell made headlines for becoming a mother aged 50. She did not share details of the birth, but had previously spoken of her desire to have a child through surrogacy, adoption or IVF. It is rare to become a mother in your 50s, but Campbell is not alone: ONS data shows that the number of live births in women aged 50-54 has quadrupled from 53 in 2001 to 218 in 2016.

However, the chances of conceiving naturally aged 50-plus are exceedingly slim, and even with IVF the chance of getting pregnant without donor eggs is around one per cent.

But it is by no means impossible, as Kelly Clarke proves – she was 50 when she gave birth to her daughter, Lyla-Rae, in March 2021.

“It was during lockdown [that] I made the decision, and I thought, I’ve got to do it now,” says Clarke.

It was undoubtedly a challenge that involved travelling abroad for IVF to Athens, but Clarke says there are advantages to becoming a first-time mother in your early 50s, including the life experience and financial freedom gained by having longer to prepare.

“For me, I was cabin crew for 23 years and I partied hard, I travelled the world, I did my sport. I’m financially secure with no mortgage, and I think now I’m ready. It’s given me the life experience I need to bring her up,” she says.

Kelly Clarke was 50 when she gave birth to her daughter
Kelly Clarke was 50 when she gave birth to her daughter

So when is the perfect decade to have a baby? Going by the data, it’s your 30s… and more specifically, aged 31, if you want to hit the biology vs financial stability sweet spot.

But if you miss it, take heart in the fact that Mathur argues against waiting for the “right” time.

“We know that financially there are things that are very wise to think about… but people sometimes find it takes longer than they imagine to get pregnant.”