Your Fertility Questions, Answered by Hertility’s Clinical Team

In our recent webinar, we unpacked the science behind fertility, explaining how hormones regulate ovulation, why timing matters, and how ovarian reserve naturally changes with age. We explored evidence-based ways to optimise egg and sperm health through nutrition, sleep, stress management, and reducing exposure to endocrine disruptors.

But as always, the most important part of the session was your questions. Many of them couldn’t be answered fully in the time we had live. So we’re starting something new.

Welcome to the Hertility Expert Q&A series,  a new post-webinar blog series where our clinical and research team answer your most pressing women’s health questions in depth.

This edition covers the questions submitted during our fertility science webinar, including:

• What’s the difference between folic acid and methylfolate?
• What are the best nutrition and supplement strategies for managing PCOS?
• How soon can you try again after a miscarriage?
• Should men stop alcohol and nicotine when trying to conceive?
• Can diet improve AMH levels?

This edition’s questions were answered by Emily Moreton, Clinical Services Manager at Hertility, fertility nurse, and registered nutritionist specialising in reproductive health. Emily holds a Master’s degree in Clinical Nutrition and Public Health from UCL and is a trained nutrition counsellor. Her work focuses on health-promoting behaviours, empowering individuals to improve their relationship with food, movement, and their body without restrictive dieting.

​​Her clinical expertise supports individuals in optimising fertility, managing PCOS and hormonal symptoms, maintaining a healthy pregnancy, and navigating menopause with confidence.

We’ve rounded up every answer here so nothing gets lost in your inbox.

Folic acid vs methylfolate: what’s the difference and which should you take?

If you’re trying to conceive, you’ve likely been told that folic acid is non-negotiable. But then you see supplements advertising “methylfolate” or “5-MTHF” and suddenly the choice feels far less straightforward. Here’s what you actually need to know.

The basics first. Folate is the natural form of vitamin B9 found in food. Folic acid is the synthetic version used in most prenatal supplements and fortified foods. Methylfolate, also known as 5-methyltetrahydrofolate (5-MTHF)  is the biologically active form your body ultimately uses. When you take folic acid, your body converts it into methylfolate through a series of enzymatic steps. For most people, this happens efficiently.

The official recommendation is . 400mcg of folic acid for all women from three months before conception through the first 12 weeks of pregnancy to reduce the risk of neural tube defects (NTDs) like spinal bifida. This recommendation is backed by major health bodies including the NHS and CDC, and is supported by decades of large-scale clinical trial data. Folic acid is currently the only form of folate clinically proven in human trials to significantly reduce NTD risk.

So why does methylfolate exist as an alternative? Some people carry variations in a gene called MTHFR, which can reduce how effectively the body converts folic acid into its active form. For those individuals, methylfolate may raise blood folate levels more efficiently because it bypasses this conversion step entirely.

The catch is that methylfolate has not been put through the same rigorous, large-scale trials as folic acid for NTD prevention and at this point, it would be unethical to design such a trial, because it would require withholding a known protective intervention from pregnant women. 

Which is better absorbed: Folic Acid or Methylfolate?

Folic acid is actually very well absorbed, and crucially it is the form used in the large clinical trials that proved it prevents neural tube defects like spina bifida. That is why public health bodies, including the NHS, recommend 400 micrograms of folic acid daily before conception and during the first trimester.

However, this dose needs to be increased to 5 milligrams daily (prescription-only in the UK) in certain higher-risk situations.

When is a higher 5mg dose of Folic Acid recommended?

A higher 5mg dose (prescription-only in the UK) may be recommended if you:

• Have previously had a pregnancy affected by a neural tube defect
• Have diabetes
• Have epilepsy and take anti-epileptic medication
• Carry certain genetic variants affecting folate metabolism
• Have a haematological condition such as Sickle Cell Disease or Thalassaemia
• Are taking medications that interfere with folate metabolism

When might methylfolate be worth considering? 

It may be appropriate in cases of known MTHFR variants, recurrent pregnancy loss, recurrent implantation failure, or where a previous pregnancy was affected by a neural tube defect despite folic acid supplementation. Hertility’s in-house clinical team or registered nutritionists and dieticians if you’d like some advice but ultimately it should be up to the individual to make an informed decision. A large number of fertility supplements now use methylfolate rather than folic acid and that shift isn’t without reason.

The reality is that experts are divided. Folic acid remains the gold standard in public health guidelines because it’s backed by decades of clinical trial data. Methylfolate is a promising and increasingly popular alternative, but it doesn’t yet carry the same evidence base for preventing neural tube defects in large-scale trials.

 Which foods are richest in folate? Supplementation is important, but dietary sources matter too. Good sources include spinach, kale, Brussels sprouts, broccoli, beans and lentils, eggs, oranges, fortified breakfast cereals, nuts and seeds, and wholegrains. Because folate is water-soluble and lost during cooking, steaming or microwaving vegetables rather than boiling helps preserve it.

The bottom line: for most women, folic acid remains the evidence-backed standard. If you have reason to believe methylfolate may be more appropriate for you, whether due to a genetic variant or a history of pregnancy complications, speak with your GP or Hertility’s clinical team before switching.

---

What is the best nutrition approach for PCOS and improving ovulation?

PCOS is one of the most common hormonal conditions affecting women of reproductive age and one of the most common causes of irregular ovulation. Search online for the “best diet for PCOS fertility”  or “how to improve ovulation naturally with PCOS,”  and you’ll be met with extremes: cut carbs, go keto, eliminate gluten, try fasting. The evidence doesn’t support most of it.

There is no single recommended PCOS diet. The goal of nutrition in PCOS is not restriction, it’s choosing foods that stabilise blood sugar and reduce inflammation, consistently, over time.

Understanding the link between PCOS and insulin. At its core, PCOS is often linked to insulin resistance. When insulin levels stay elevated, the ovaries produce more androgens such as testosterone, which can interfere with follicle development and regular ovulation. Managing insulin through diet is therefore one of the most evidence-based nutritional targets in PCOS.

A Mediterranean-style eating pattern is the approach with the strongest evidence base for PCOS, linked to improved ovarian health and reduced disease severity. It’s not a rigid set of rules; it’s a way of eating built around variety, quality fats, fibre, and protein.

Building a balanced plate. Rather than cutting out food groups, the goal is to build meals that keep blood glucose steady. That means including protein, healthy fats, and quality carbohydrates at every meal,what we call the golden trio.

On carbohydrates specifically: there is no strong evidence that cutting gluten or going very low-carb manages PCOS better than a balanced diet. What matters is the quality of carbohydrates. Choose low glycaemic index options, oats, pulses, beans, wholegrains  over white bread, white rice, and sugary cereals. High-fibre carbohydrates slow glucose absorption and support the gut microbiome. Aim for 30 different plant-based foods per week. Avoid ketogenic or very low-carb diets; they are difficult to sustain and can create deficiencies in folate, iron, and zinc.

On protein: it’s essential for hormone production and appetite regulation, and may help reduce androgens and increase SHBG (sex hormone binding globulin), which is often low in people with PCOS. Vary your sources: lean meat, eggs, dairy, and plant-based proteins like tofu, soy, and legumes. Pairing quality protein with low-GI carbohydrates is the most effective combination for improving insulin sensitivity.

On fats: prioritise unsaturated fats from extra virgin olive oil, avocado, nuts (especially walnuts and almonds), and seeds. Omega-3 fatty acids from oily fish like salmon, trout, mackerel, sardines  can reduce inflammation and improve insulin resistance. Aim for one to two portions per week, or consider a supplement if intake is low.

What about the common myths? There is no clinical evidence that eliminating dairy or gluten improves PCOS. Contrary to some persistent online claims, while minimising added sugar is sensible, being rigid about it to the point of stress is counterproductive.

Movement matters too. Strength training in particular is the unsung hero of PCOS management. Muscle tissue improves insulin sensitivity in ways diet alone cannot. Two to three resistance sessions per week, alongside daily movement, can meaningfully improve ovulation patterns over time.

When lifestyle isn’t enough. If your cycles are consistently longer than 35 days, or you’re going months without ovulating, lifestyle changes may need to be paired with medical support. Letrozole is now considered first-line ovulation induction treatment in many guidelines. If you have significant insulin resistance, metformin may also be appropriate. These are decisions to make with your doctor, not in addition to or instead of seeking care.

Before making major dietary changes, particularly if you have diabetes, thyroid conditions or a history of disordered eating, speak with your GP or Hertility’s in-house nutrition team to ensure your plan is safe and personalised.

---

What are the best supplements for managing PCOS?

PCOS isn’t a single condition. For some women, insulin resistance is the main driver. For others, high androgen levels, inflammation, or disrupted ovulation are more central. The right supplement approach depends on what’s actually happening in your body, which is why blanket recommendations rarely serve women with PCOS well.

Myo-inositol has the strongest evidence base of any supplement in PCOS. It improves insulin signalling at a cellular level, which can lower circulating insulin, reduce androgen levels, and improve ovulation, particularly in women with insulin resistance, which is common in PCOS even at a healthy weight. If you’re already taking metformin or other glucose-lowering medication, discuss inositol with your GP or Hertility clinician before starting.

Vitamin D is another common and important gap. Deficiency is significantly more prevalent in women with PCOS and is associated with poorer ovulation and increased insulin resistance. In the UK, the recommendation is to supplement with 10 micrograms (400 IU) of vitamin D daily, particularly in winter. Some people benefit from supplementing year-round, and your GP can test your levels to determine whether a higher dose is needed.

Omega-3 fatty acids are useful in PCOS, particularly where triglycerides are elevated or inflammatory markers are raised. They may support metabolic health and reduce inflammation. Dietary sources like oily fish should come first, with supplements added where intake is consistently low.

CoQ10 is sometimes recommended for women concerned about egg quality, particularly those over 35 or undergoing fertility treatment. It supports mitochondrial function, which is crucial for egg maturation and embryo development. Supplementation for 12 weeks in people with PCOS has also been shown to have beneficial effects on glucose metabolism and cholesterol levels.

NAC (N-acetylcysteine) has been studied for its effects on insulin sensitivity and ovulation in PCOS. Some research suggests it may improve ovulation rates, including in women resistant to certain fertility medications. It should be used thoughtfully, as it can interact with other treatments and isn’t appropriate for everyone.

The important caveat: supplements work best when they’re targeted to your actual profile. The most effective plan reflects your hormone results, metabolic markers, age, and reproductive goals. Before starting any supplement, speak with your GP or Hertility’s

---

How long should you wait to try again after miscarriage, and how can you support your cycle in the meantime?

After a pregnancy loss, two questions tend to surface at once: when is it safe to try again, and am I ready? They’re both valid, and the answers are different.

Physically, the body often recovers sooner than you might be ready. Ovulation can return as early as two to four weeks after an early miscarriage, and most women will have a period within four to six weeks. NHS guidance reflects the current evidence: after an uncomplicated early loss, there is usually no medical need to delay trying again once you feel ready. Conceiving in the months following a miscarriage does not appear to increase the risk of another loss.

You may be advised to wait if there were complications like heavy bleeding, infection, surgical management such as ERPC  or if the loss occurred later in pregnancy. In those situations, your doctor will guide you on timing.

Supporting recovery in the meantime. There isn’t a way to “reset” your cycle, but you can support recovery gently. Continue folic acid. If the bleeding was heavy, check iron levels with your GP. Prioritise sleep, eat regularly, and return gradually to exercise rather than pushing hard. If your period hasn’t returned after eight weeks, or if cycles become very irregular, speak with your doctor to rule out retained tissue or hormonal imbalances such as thyroid dysfunction or elevated prolactin.

If you’d like reassurance before trying again, a comprehensive hormone test can assess thyroid function, prolactin and ovarian reserve. Reviewing these results with a Hertility clinician can help identify any underlying issues that may need addressing and give you a clearer plan moving forward. Please note that at Hertility we suggest waiting to do a Hertility hormone test until your third cycle after a pregnancy loss before testing, to allow hormone levels to stabilise and results to be meaningful.

When to seek further investigation. If you have experienced two or more losses, or if the loss occurred later in pregnancy, NHS guidelines recommend further investigations. These may include blood tests for antiphospholipid syndrome, thyroid disease, or diabetes; imaging of the uterus to check for structural concerns; and in some cases genetic testing. While the idea of investigations can feel overwhelming, many people find that having answers or reassurance that everything looks normal helps them move forward with greater confidence.

The right time to try again is when you feel physically recovered and emotionally steady enough to sit with the uncertainty of early pregnancy. There is no universal answer. What matters is that you feel supported and informed, not rushed, and not left to navigate it alone.

---

Are there specific foods that can improve AMH levels?

AMH (anti-Müllerian hormone) is a marker of ovarian reserve, essentially, an indicator of how many eggs remain in the ovaries. It’s one of the most searched fertility metrics, and it generates a lot of anxiety. So before exploring what nutrition can and can’t do, one important point: AMH does not measure egg quality, and it does not predict natural conception month-to-month in women who are ovulating regularly. It is one marker among many, not a fertility score.

With that context in place, what does the evidence say about supporting ovarian reserve through diet and lifestyle?

We are born with a set number of eggs, and that number cannot be increased. However, there is emerging research suggesting that lifestyle and nutrition may influence the rate of AMH decline and support the hormonal environment in which eggs mature. The findings are promising but not yet definitive, and some are currently specific to certain populations. That said, the foods and habits associated with ovarian support are cornerstones of overall health anyway,so they’re worth prioritising regardless.

Dairy intake has been associated in some research with a slower natural rate of AMH decline over time. Omega-3 fatty acids may have beneficial effects on ovarian markers. Antioxidants are particularly relevant because oxidative stress is notably higher in women with premature ovarian insufficiency (POI). Foods rich in selenium and vitamin E (nuts, seeds, leafy greens), folate and vitamin C (citrus, berries, legumes) all contribute to reducing that oxidative burden.

On supplementation: higher folate intake, particularly from supplements has been positively associated with modestly higher ovarian reserve in some studies. Taking a high-quality prenatal multivitamin may also positively influence AMH levels. Selenium and vitamin E in supplement form have shown specific promise in supporting both AMH and antral follicle count in women with POI.

Lifestyle factors that matter: maintaining a BMI between 19 and 30, engaging in moderate exercise, reducing ultra-processed food intake to lower systemic inflammation, and minimising exposure to endocrine-disrupting chemicals (EDCs) — particularly phthalates found in synthetic fragrances and certain plastics — are all associated with better hormonal health.

The most important thing to know about a low AMH result is that it needs context. Hertility’s Advanced At-Home Hormone and Fertility Test can assess not just AMH but also cycling hormones, thyroid function, prolactin, and other markers that influence cycle regularity. Speaking with a Hertility clinician can help you understand what your AMH actually means for your situation, whether timing matters, whether fertility preservation is worth considering, and what steps, if any, are appropriate.

---

A note on getting personalised support

The questions above cover a wide range of situations, and the honest answer to most of them is that the right approach depends on your individual hormone profile, health history, reproductive goals, and stage of life. General guidance is a starting point, not a destination.

Before making significant dietary changes, particularly if you have diabetes, thyroid conditions, a history of disordered eating, or are taking medication, speak with your GP or Hertility’s in-house clinical team. Our registered nutritionists, dieticians, and gynaecologists can review your results and give you a plan that’s built around you, not a generalisation.

If you’d like to understand your hormonal health in more detail, Hertility’s Advanced At-Home Hormone and Fertility Test a starting point for clearer answers and better-informed decisions.