Infertility: What Is It? And How Much Does Age Really Matter?
Written by Jess Kasriel, Fertility Nutritional Therapist / Practitioner
If you're trying to conceive and it isn't happening as quickly as you'd hoped, it's completely understandable to start asking questions.
Could something be wrong? Is my age affecting my fertility? Should I be doing more? Should I have my hormones tested? Is there something I'm missing?
And once you start Googling, it can feel like the list of things you should be doing gets longer and longer.
Infertility can feel incredibly isolating, but you're certainly not alone. The World Health Organization estimates that around 1 in 6 people worldwide experience infertility during their lifetime. Infertility can affect women, men, or both partners, and sometimes no clear cause is identified.
That is a huge number.
And yet fertility and reproductive health can still be surprisingly difficult to talk about.
Periods, ovulation, painful or irregular cycles, miscarriage, sperm health, fertility testing and struggling to conceive can all feel like very private subjects.
I believe we need to change that.
Because understanding your fertility doesn't have to mean becoming obsessed with it. And supporting your health doesn't have to mean adding another 20 things to your to-do list.
It can simply mean understanding your body, getting the right information and working out what is actually relevant to you.
What is infertility?
The World Health Organization defines infertility as a disease of the reproductive system where pregnancy has not been achieved after 12 months or more of regular unprotected sexual intercourse. Infertility can be primary or secondary and may be caused by male factors, female factors, a combination of both, or remain unexplained.
Primary infertility generally refers to someone who has never achieved a pregnancy.
Secondary infertility refers to difficulty achieving a pregnancy after a previous pregnancy.
It's important to remember that the 12-month definition is a clinical definition. It doesn't mean you have to sit back and do nothing for a year before paying attention to your health or asking questions.
If you have concerns about your fertility, it's reasonable to speak with your GP or fertility specialist, particularly if you have irregular or absent periods, a known fertility condition, previous pelvic surgery or other factors that may affect fertility.
And alongside appropriate medical care, there are areas of your nutrition, lifestyle and wellbeing that may be worth looking at too.
What causes infertility?
There isn't one single cause of infertility.
Female infertility can be associated with a number of factors, including:
Ovulation problems, including those associated with conditions such as PCOS
Problems affecting the fallopian tubes
Endometriosis
Fibroids or other uterine factors
Age-related changes in fertility
Certain hormonal or endocrine conditions
Previous pelvic surgery or infection
Some genetic factors
Lifestyle factors such as smoking, alcohol intake and weight
Sometimes, no clear cause is identified
Male factors can also play an important role, including sperm production, sperm movement and sperm quality.
In fact, infertility can involve male factors, female factors, both partners, or remain unexplained.
This is why I don't believe fertility should automatically be framed as a woman's problem.
Fertility is a shared journey.
If you're struggling to conceive, both partners may need appropriate assessment and support.
So, how much does age really matter?
This is one of the questions I hear most often.
And the honest answer is: yes, age is an important factor in female fertility — but it isn't the whole story.
Female fertility generally declines with age, with age being an important predictor of the chance of conceiving naturally and through fertility treatment. This is largely related to changes in both the number and quality of the eggs remaining in the ovaries.
However, there is also considerable individual variation.
Two women of the same age can have very different reproductive histories, health circumstances and fertility journeys.
So while age matters, your age is not your fertility story.
And this is where I think it's important to move away from fear.
If you're in your 30s or 40s and trying to conceive, you may have already seen headlines telling you that your biological clock is ticking.
That kind of messaging can create huge amounts of anxiety.
My approach is different.
I want you to have the information you need to make informed decisions about your fertility — without feeling that you need to panic or do everything perfectly.
What about AMH and ovarian reserve testing?
You may have heard of AMH (anti-Müllerian hormone) testing.
AMH is one of the markers used to assess ovarian reserve — essentially, the remaining pool of follicles in the ovaries.
AMH can be useful information in certain fertility and IVF settings, particularly when clinicians are assessing how the ovaries may respond to stimulation.
But this is where things can get confusing.
AMH is not a simple fertility test.
Current guidance from the American Society for Reproductive Medicine states that ovarian-reserve markers such as AMH are poor predictors of reproductive potential when considered independently of age. A lower AMH result does not automatically mean that you cannot conceive naturally.
The updated 2026 NICE fertility guidance similarly recommends using maternal age as an initial predictor of the overall chance of spontaneous conception, rather than treating ovarian-reserve testing as a standalone measure of fertility.
So if you've had an AMH test and received a result that has left you worried, please don't interpret that number in isolation.
Your fertility is much more complex than one blood test.
A fertility assessment may consider your age, menstrual cycle, ovulation, medical history, previous pregnancies, partner's sperm health and other individual factors alongside any relevant testing.
What can you actually do to support your fertility?
This is the part I really care about.
Because while there are some things we cannot control — including our chronological age — there are many aspects of our health that we can pay attention to.
Your nutrition and lifestyle don't provide a magic solution to infertility, and they cannot guarantee pregnancy.
But they can form an important part of your overall health and wellbeing while you're trying to conceive.
Depending on your individual circumstances, areas worth exploring may include:
🌿 Nutrition — Are you eating enough? Are you getting a varied, nutrient-dense diet? Are there nutritional gaps worth addressing?
🥑 Blood sugar and metabolic health — Particularly if you have symptoms or a diagnosis associated with insulin resistance or PCOS.
🩸 Nutrient status — Are there deficiencies or nutritional concerns that would be useful to discuss with your GP or healthcare professional?
🌙 Sleep and recovery — Are you constantly running on empty?
🧘♀️ Stress and nervous-system wellbeing — Not because stress is the cause of infertility, but because living through fertility struggles can be incredibly demanding.
🚶♀️ Movement — Finding an approach to exercise that supports your health without pushing your body into exhaustion.
🍷 Alcohol, smoking and caffeine — Looking honestly at your current habits and what changes may be appropriate for you.
💛 Emotional wellbeing — Giving yourself support rather than turning fertility into another area where you feel you are failing.
And importantly, none of this needs to become another fertility checklist.
You don't have to do everything perfectly
This is something I really want women to hear.
When you're trying to conceive, it can become very easy to fall into the mindset of:
Am I eating the right foods?
Am I taking the right supplements?
Am I exercising too much?
Am I exercising enough?
Should I stop drinking coffee?
Should I test my hormones?
What if I've left it too late?
Before you know it, trying to conceive has become another full-time job.
It shouldn't have to feel that way.
Supporting your fertility isn't about finding the perfect diet, taking every supplement or controlling every variable.
It's about understanding your body and identifying the areas that may genuinely be worth focusing on.
That's where personalised support can be so valuable.
What does this mean for you?
If you're trying to conceive and feeling overwhelmed by everything you're being told you should be doing, you don't necessarily need more information.
You may simply need someone to help you make sense of it.
As a Fertility Nutritional Therapist / Practitioner based in Finchley, North London, I work with women who want to understand their fertility, cut through the noise and create a more personalised approach to their health.
My work combines fertility education, nutrition, lifestyle support, healing, Reiki and mind-body practices.
The aim isn't to promise you a particular fertility outcome.
It's to help you feel more informed, supported and empowered as you navigate your own journey — alongside appropriate medical care where needed.
Want some personalised clarity?
If you're struggling to conceive and wondering what actually matters for you, my Fertility Clarity Session is a focused 60-minute 1:1 session designed to help you step out of the overwhelm and identify practical next steps.
We'll look at your fertility journey, your circumstances and your priorities rather than giving you another generic fertility checklist.
You can leave with greater clarity, personalised guidance and a clearer idea of what to focus on next.
Fertility Clarity Session — 60 minutes | £222
I also offer:
Fertility Reset £1,111 (payment plan available) — a 6-week personalised 1:1 programme to help you understand your body, uncover your fertility foundations and create a clear path forward.
Fertility Rebalance £2,250 (payment plan available)— a 3-month deeply personalised 1:1 programme for women who want ongoing support, accountability and deeper work throughout their fertility journey.
Jess x
References
World Health Organization (WHO) — Infertility: definition, causes and global prevalence.
NHS — Causes of infertility.
NICE (2026) — Fertility problems: assessment and treatment.
American Society for Reproductive Medicine (ASRM) — Testing and interpreting measures of ovarian reserve.
American Society for Reproductive Medicine (ASRM) — Fertility evaluation of infertile women.
