Is there a ‘best age’ to get pregnant with PMOS? A fertility specialist explains

If you have PMOS, you may have questions about what your diagnosis means for your fertility – particularly when it comes to your biological clock. Does having a ‘higher’ ovarian reserve mean you have longer to have a baby? Is there a ‘best age’ to get pregnant with PMOS? And if your periods are irregular, should you start trying sooner?

The condition, previously known as polycystic ovary syndrome (PCOS), has been proposed a new name – polyendocrine metabolic ovarian syndrome, or PMOS – to better reflect the fact that this is about much more than the ovaries. It can involve hormonal, metabolic and reproductive factors, and it can affect women in very different ways. 

At Clínica Tambre, our long-time go-to clinic in Spain, fertility specialists support patients navigating PMOS and conception plans on a daily basis. With nearly 50 years of experience in assisted reproduction, Tambre takes a personalised approach to fertility, looking at the individual factors that may be influencing a patient’s chances of conceiving.

For this guide, we spoke to Dr. Abraham Zavala, Scientific Director of Clínica Tambre, about what PMOS means for fertility, whether age matters, how to improve your chances of conception and when it makes sense to seek specialist help. 

Dr. Zavala was appointed Scientific Director of Tambre and its Foundation in July 2026, bringing a focus on clinical experience, scientific rigour and personalised reproductive medicine. 

Is there a ‘best age’ to get pregnant with PMOS?

There is no single “best age” to get pregnant with PMOS, as fertility depends on several individual factors. However, age remains an important part of the reproductive picture.

“Women with PMOS often have a high ovarian reserve, but this does not protect against the age-related decline in egg quality that affects all women,” explains Dr. Zavala.

“For this reason, when circumstances allow, trying to conceive before the age of 35 is generally associated with better reproductive outcomes.”

PMOS can also affect fertility through irregular or absent ovulation and, in some women, through metabolic factors such as insulin resistance. This is why the most appropriate timing should always be considered individually, taking into account age, ovulation, hormonal and metabolic health – and any other fertility factors that may be present.

The key message is that having PMOS does not mean a woman cannot become pregnant, but it is advisable not to assume that a higher ovarian reserve cancels out the effect of age on fertility.

That distinction is particularly important because ovarian reserve and egg quality are not the same thing. A woman can have a relatively high ovarian reserve – meaning she has a larger number of follicles – while still experiencing the natural age-related changes in egg quality.

So, there isn’t a one-size-fits-all answer. But age should form part of the conversation, alongside your individual reproductive and metabolic health.

Does PMOS affect fertility more as you get older?

“Not necessarily,” says Dr. Zavala.

“PMOS does not simply become more severe with age, and some women may even experience changes in their ovulatory pattern over time.”

However, natural age-related decline in egg quality still applies to women with PMOS. This means that, even if ovarian reserve is relatively high, age can still have an important influence on the chances of conception.

“So, rather than saying that PMOS itself affects fertility more as a woman gets older, it is more accurate to say that the effects of the condition and the effects of reproductive ageing can overlap.”

This is an important distinction.

For some women, PMOS may make it harder to conceive because they do not ovulate regularly. As age increases, there is an additional consideration: the quality of the eggs naturally declines.

A high ovarian reserve can therefore be reassuring in one respect, but it shouldn’t be interpreted as a way of stopping or reversing reproductive ageing.

Can you get pregnant naturally with PMOS?

Yes.

Having PMOS does not mean that you will automatically need fertility treatment.

“Many women with PMOS can become pregnant naturally, particularly if they are ovulating, even if their cycles are not always completely predictable,” says Dr. Zavala.

The difficulty for some women is that irregular or absent periods can mean that ovulation is also irregular or absent. This can make it more difficult to know when you are fertile and can reduce the number of opportunities to conceive.

If you have relatively regular cycles and no other known fertility factors, there’s no reason why you cannot try to conceive naturally.

However, if your periods are very irregular or absent, it may be worth seeking medical advice rather than simply waiting and hoping that pregnancy happens. On this point, the EMJ recently headlined with a super-interesting survey covering why women with PMOS encounter so much delay in getting support with fertility, following diagnosis. 

A fertility assessment can help establish whether irregular ovulation is the main difficulty or whether there are other factors that should also be investigated.

And if you’re using an app or cycle tracker to identify your fertile window, remember that predicting ovulation can be more difficult when cycles are irregular. In that situation, understanding whether you are actually ovulating may be more useful than relying solely on predicted fertile days.

How can you improve your chances?

“The best approach is to identify what is affecting fertility in each individual case and address those factors specifically,” says Dr. Zavala.

For some women with PMOS, lifestyle changes can help improve insulin sensitivity, support more regular cycles and encourage ovulation.

“A balanced diet, regular physical activity and weight loss, when medically indicated, may all form part of this approach.”

It’s worth stressing that this is not about trying to reach a particular body size before you can safely try for a baby. Rather, where there are metabolic factors such as insulin resistance or weight-related health concerns, addressing them may form part of a broader fertility plan.

If ovulation remains irregular or absent, medication can be used to stimulate ovulation.

“In other cases, particularly when there are additional fertility factors or simpler treatments have not been successful, assisted reproduction such as IVF may be considered.”

The important point, Dr. Zavala says, is that treatment should be tailored to the individual rather than following a single approach for everyone with PMOS.

There may be a relatively straightforward explanation for why pregnancy isn’t happening – such as irregular ovulation – but the only way to know is to assess the individual situation.

What really works (and what’s a myth)?

If you’re searching online for fertility advice, it can be difficult to separate evidence-based advice from the latest supplement, diet or hack.

According to Dr. Zavala, the first thing to understand is that irregular ovulation is something that can be treated.

“If a woman is not ovulating regularly, that is something we can actually treat. We have effective medication to induce ovulation, and if that is not enough, there are further fertility treatments available depending on the individual case.”

One myth to be cautious about is the idea that having a high ovarian reserve means fertility is automatically ‘good’.

“Women with PMOS often have many follicles, but that does not necessarily mean they are ovulating regularly or that age no longer matters.”

Dr. Zavala also highlights the distinction between a high AMH – which can be seen in PMOS – and spontaneous fertility. A high AMH may indicate a high number of available follicles, but it does not necessarily mean that a woman is ovulating regularly.

He recommends caution around anything promising a quick cure.

“PMOS is a complex condition, so the most useful thing is to understand what is actually preventing pregnancy in that particular woman and treat that, rather than trying every supplement or fertility trend you come across.”

When should someone with PMOS see a fertility specialist?

When to seek help depends on your age, your menstrual cycle and your wider fertility picture.

“If a woman with PMOS is under 35, has fairly regular cycles and no other known fertility issues, it is usually reasonable to try for up to 12 months before seeking specialist advice,” says Dr. Zavala.

“From the age of 35, we would normally recommend looking into things sooner, after around six months.”

But there is an important caveat.

“If periods are very irregular or absent, I would not necessarily suggest waiting that long, because it may mean ovulation is not happening regularly.”

Earlier assessment may also be advisable if there are other known fertility factors.

A fertility assessment can help establish whether irregular ovulation is the main difficulty or whether other factors should also be investigated, allowing treatment to be adapted accordingly.

What about women with PMOS who aren’t ready to have a baby yet?

A PMOS diagnosis doesn’t mean that a young woman needs fertility treatment simply because she might want children in the future.

But understanding your reproductive health can be useful.

“For younger women who are not yet trying for a baby, having PMOS does not mean they need fertility treatment,” says Dr. Zavala.

“But if they are thinking about their future fertility, it can still be useful to understand how regularly they ovulate and whether there are any hormonal or metabolic factors that may be relevant later on.”

This can be particularly valuable if periods are very irregular or absent.

I’m in my 20s and have PMOS – what should I do?

Dr. Zavala has three priorities for a woman in her 20s who has been diagnosed with PMOS and is thinking about future conception.

1. Understand your cycle

“First, I would want her to understand her cycle properly – whether she is ovulating regularly and how predictable her periods really are.”

You don’t need to turn your cycle into a full-time project, but knowing whether you are ovulating regularly can give you useful information about your reproductive health.

2. Look at your metabolic health

“Second, I would look at her metabolic health. If there is insulin resistance, excess weight or another metabolic issue, addressing that before pregnancy can make a real difference.”

This is one of the reasons the proposed PMOS terminology is significant: it reflects the broader hormonal and metabolic nature of the condition rather than suggesting that it is simply an ovarian issue.

3. Don’t ignore very irregular periods

“And third, I would encourage her not to wait until she has been trying for a long time before asking for advice if her periods are very irregular or absent.”

Being in your 20s is reassuring in many ways, but PMOS can still affect ovulation. Understanding where you stand can help you make decisions about conception later, without creating unnecessary urgency now.

What about a woman in her 30s?

“In your 30s, I would be a little more proactive,” says Dr. Zavala.

“I would want to know whether you are ovulating regularly, whether there are any metabolic issues that need attention, and how long you plan to wait before trying to conceive.”

There is still very often good reproductive potential in this age group, but Dr. Zavala emphasises that women shouldn’t assume that having PMOS and a high ovarian reserve gives them unlimited time.

“If cycles are very irregular or pregnancy is becoming a priority, it makes sense to assess things earlier rather than simply waiting.”

This doesn’t mean that everyone with PMOS in their 30s needs to start fertility treatment immediately. It means understanding the factors that could affect your individual fertility can help you make decisions with more information.

For some women, that may mean trying naturally. For others, it may mean addressing ovulation or metabolic health first. And for some, depending on age and individual circumstances, fertility preservation may be something worth discussing.

And what about PMOS in your early 40s?

“In your early 40s, I would advise getting a fertility assessment quite early if pregnancy is the goal,” says Dr. Zavala.

“PMOS may mean that ovarian reserve is still relatively high, but that does not protect against the effect of age on egg quality. I would want to understand the full fertility picture, rather than focus only on the PMOS diagnosis.”

The aim isn’t to create anxiety, but to avoid losing time if there is something that needs to be addressed.

A high ovarian reserve can sometimes be reassuring to see on a fertility test, but it doesn’t tell the whole story. Age, ovulation, egg quality and other fertility factors all need to be considered together.

What if you’re diagnosed with PMOS at 39 or 40?

A diagnosis at 39 or 40 does not mean that pregnancy is no longer possible.

However, Dr. Zavala recommends looking at fertility sooner rather than later if pregnancy is the goal.

“Some women only discover they have PMOS when they start trying to conceive, particularly if their symptoms were mild or had never been investigated in detail.”

At 39 or 40, a specialist will want to understand whether ovulation is taking place and whether there are any other factors affecting fertility, while also taking age into account.

“The important thing is not to assume that a high ovarian reserve, which is common in PMOS, removes the effect of age on egg quality. It does not.”

Does PMOS increase the risk of miscarriage?

There is evidence suggesting that women with PMOS may have a higher risk of miscarriage, particularly in early pregnancy.

However, this does not mean that miscarriage is inevitable.

“The level of risk can vary considerably from one woman to another,” says Dr. Zavala. “Factors such as weight, insulin resistance and other metabolic issues may also play a role.”

For that reason, it is important to look at the overall health of the patient before and during pregnancy, rather than considering PMOS in isolation.

Most importantly, PMOS is not a diagnosis of infertility.

Three things to keep in mind

1. PMOS does not mean you can’t get pregnant.

Many women with PMOS can conceive naturally, particularly if they are ovulating. If ovulation is irregular or absent, there are treatments that can help.

2. A high ovarian reserve doesn’t cancel out age.

Women with PMOS often have a relatively high ovarian reserve, but this does not protect against the natural age-related decline in egg quality.

3. Don’t wait unnecessarily for help.

If you’re under 35, trying naturally for up to 12 months may be reasonable if your cycles are relatively regular and there are no other known fertility factors. 

From 35, assessment is generally recommended after around six months. But if your periods are very irregular or absent, it can make sense to seek advice earlier.

That’s where personalised fertility assessment comes in.

Clínica Tambre has almost 50 years of experience in assisted reproduction and takes an individualised approach to fertility care, assessing factors including ovulation, ovarian reserve, metabolic health and other potential causes of fertility difficulties.

And if you’re still getting your head around the terminology, our guide to PMOS meaning explains why the condition has been given a proposed new name – and what that change means for patients.

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