Fertility isn’t something most of us plan to think about early. For many people, it only comes into focus when pregnancy doesn’t happen as expected. But in the UK, around 1 in 6 people, and 1 in 7 couples, experience fertility problems at some point, which makes this far more common than many realise.
Thinking about fertility earlier isn’t about assuming there will be a problem. It’s about understanding how fertility changes over time, what can affect it, and when it might be sensible to check where you stand.
- Lifestyle and fertility
- When to get tested
- What fertility tests show
- Age and treatment limits
- Moving forward
Fertility and age: what actually changes?
For women, fertility is closely linked to eggs.
You’re born with all the eggs you’ll ever have. Over time, both the number and quality of those eggs decline. This happens gradually through your twenties and early thirties, then more noticeably from around age 35. Because only one egg is released each month, fewer eggs can mean it takes longer to conceive. Changes in egg quality can also increase the risk of miscarriage, often linked to chromosomal changes in the egg.
The average age of menopause in the UK is around 51, but fertility declines well before this. Ovulation often becomes less predictable years earlier, even while periods are still regular. Menopause itself isn’t a reliable indicator of fertility potential.
Men’s fertility changes more slowly, but age still plays a role. Sperm quality, including movement and DNA integrity, can decline over time. Male factors contribute to around half of fertility issues, either alone or alongside female factors.
Lifestyle factors that can affect fertility earlier than expected
Age matters, but it doesn’t act alone. Everyday habits can influence fertility, sometimes more than people expect.
Vaping and smoking
Vaping is often seen as a safer alternative to smoking, but nicotine still affects blood flow and hormone regulation — both of which matter for fertility.
In women, smoking is known to affect both the quantity and quality of eggs. People who smoke tend to reach menopause around five years earlier than non-smokers, which reflects a faster decline in ovarian reserve. Changes in egg quality can also increase the risk of miscarriage.
In men, nicotine exposure is linked to a lower sperm count and reduced motility, meaning sperm may be fewer in number and less able to swim effectively.
Research into vaping is still ongoing, but current evidence suggests it isn’t neutral when it comes to fertility. While it may reduce exposure to some of the harmful chemicals found in cigarettes, nicotine itself can still have an impact on reproductive health.
Anabolic steroids and testosterone use
Anabolic steroids and testosterone supplements can significantly suppress sperm production, sometimes to the point where no sperm are produced at all. Recovery isn’t always guaranteed and, when it does happen, it can take many months after stopping. This often comes as a surprise, particularly for people who feel physically fit and otherwise healthy.
If you’re experiencing low testosterone levels, it’s worth knowing that there are ways to support testosterone without suppressing sperm production. These options depend on the cause and your individual circumstances, so it’s important to speak to your GP or a fertility specialist before starting or continuing any hormone treatment.
Alcohol
Regular alcohol intake can affect ovulation and sperm quality. It’s not about cutting everything out, but frequent drinking can compound age-related changes.
Read our 7 top tips on how to boost your fertility
Weight changes
Hormone balance is sensitive to body weight.
- Higher body weight can disrupt ovulation and reduce sperm quality
- Very low body weight can stop ovulation altogether
This isn’t about perfection, but extremes can have an impact.
Read more about how weight can affect fertility
Sleep and long-term stress
Poor sleep and ongoing stress don’t directly cause infertility, but they can interfere with hormone signalling over time, especially when combined with age-related changes.
Learn more about how stress can affect fertility
When should you consider checking your fertility?
There’s no single “right” moment, but there are situations where checking earlier can be helpful rather than reactive.
You may want to consider fertility testing if:
- You’re over 30 and not planning to try for a few years
- You’ve been trying to conceive without success
- Your periods are very irregular, very painful, or have stopped
- You’ve used anabolic steroids or testosterone in the past
- You vape, smoke, or have done for several years
- You’ve had pelvic surgery, cancer treatment, or known infections
- You want clear information now, rather than assumptions later
Guidance from the NHS and regulation by the Human Fertilisation and Embryology Authority support early investigation where there are risk factors. Waiting isn’t always a neutral option, particularly as fertility changes with age.
What tests should you have?
At Care Fertility, fertility testing is carried out before your consultation with a fertility expert. This means results are ready to be reviewed and explained during the appointment, allowing for informed, practical discussions.
Our pre-treatment bundle includes:
For women
- Blood tests to measure hormone levels, including Anti-Müllerian Hormone (AMH), Full blood count (FBC), Blood glucose (HbA1c), Thyroid stimulating hormone (TSH, and vitamin D, which gives an indication of ovarian reserve and overall health
- An ultrasound scan to assess the ovaries, uterus, and antral follicle count
For men
- A semen analysis looking at sperm count, movement (motility), and shape (morphology)
These tests don’t predict the future, but they do provide a clear snapshot of fertility now.
Age limits and IVF in the UK
It’s also important to understand the practical limits around treatment, as these can affect planning more than people expect. At Care Fertility, we follow clear age limits around treatment to make sure care is safe and responsible.
Our treatment age limits are:
Using your own eggs
Egg collection must take place before your 46th birthday, and any resulting pregnancy must be delivered before your 50th birthday.
Using donor eggs or previously frozen embryos
Treatment can continue later, but pregnancy must still be delivered before your 50th birthday.
These limits are set by Care Fertility in line with our clinical governance and licensing requirements. They apply regardless of how healthy or fit someone feels.
Knowing this earlier can help with planning. For some people, it brings timelines forward. For others, it opens up conversations about options such as egg freezing, when eggs are younger and more likely to respond well to treatment.
Fertility information isn’t a commitment
Thinking about fertility doesn’t mean committing to treatment. It doesn’t mean IVF is inevitable. For many people, it starts and ends with understanding their body a bit better.
Having clear information earlier can make later decisions feel measured rather than rushed. And with 1 in 6 people affected by fertility issues in the UK, asking these questions isn’t pessimistic or dramatic, it’s practical.
