Torwen:
Nutrition Podcast. My name is Torwen Eerkins, and I’m joined by my co-host, Aidan Muir. And today’s episode will focus specifically on nutrients for female fertility. We’re going to cover key nutrients, some secondary players, and then wrap up with a few practical recommendations.
Before we start, I want to make a quick disclaimer. Fertility is, of course, multifactorial. There is no single nutrient, supplement, or food that will be the difference between getting pregnant and not. Genetics, age, hormonal health, body composition, stress, and your partner’s health all play a big role, too.
Aidan:
And even within nutrition, we’re only going to focus on nutrients for this one. We wanted to get comprehensive coverage of that one specific section. This can be a massive topic, and there is so much we could say. We’re talking through the lens of improving the odds of getting pregnant.
We’re also talking through the lens of having a healthy baby, or improving those odds as well. One area we’re focused on is what we call the 90-day preconception window. Obviously, 90 days is an arbitrary line drawn in the sand somewhere. But it is a target that roughly matches the life cycle of both eggs and sperm.
Many nutrients play important roles during this window. That does not mean there is nothing that can be done before that helps. But that is a really important window. There is other dietary stuff, as I said. There is energy availability, macronutrient balance, alcohol, and a bunch of things. But we’re just going to focus on nutrients here.
Torwen:
Absolutely. So let’s get straight into it. Let’s start with folate. Folate is probably the most well-known in this space. It is also one of the most well-established interventions in reproductive health generally. Most people have probably heard that they should take folic acid when trying to get pregnant.
And there is pretty strong evidence behind it. It is primarily for neural tube defect prevention, including conditions like spina bifida. The evidence here is really solid. It also supports DNA synthesis and cell division. These are critical during those early stages of pregnancy. That makes it ideal to start preconception. The standard recommendation here is around 400 micrograms of folic acid daily. Sometimes, it pushes a little higher, one to three months before conception.
Aidan:
So folate is the food form. Folic acid is a synthetic supplement form. There is concern about the MTHFR gene variant, but there is a lot to unpack here. Firstly, before I go through this, have we done a podcast on that? Or what that Leah?
Torwen:
Probably Leah.
Aidan:
Okay. There is also a blog post on the website that goes into detail. If you really want an in-depth dive into that, we have heaps there. But I will do a summary here. This is a really important part of speaking about folic acid. Unpacking the first bit, about 40 to 60% of people carry a variant on that MTHFR gene. If this was an issue at that scale, the standard advice would not be regular folic acid.
We have a lot of research, as you said, Torwen, showing improvements overall with people taking folic acid. So we know there are positives there across the board. But there are cases where it is arguably more of a concern. For example, people having two variants, or two copies of the same variant. Even more specifically, it may matter if there is a build-up of homocysteine as well. So, if there is a concern, there is another alternative option.
That is methylfolate instead of regular folic acid supplementation, which can get around this. But it is worth noting that most larger conservative fertility organisations still strongly prefer folic acid. That is outside of very niche cases, largely due to the wealth of research we have. I still feel like it is worth a mention. There are heaps of deep diving that can be done there. But as a general broad overview, folic acid is the standard recommendation in most cases.
Torwen:
For sure. Not supplementing with folic acid due to MTHFR concerns is probably a much larger risk than supplementing.
Aidan:
There is one more thing I’ll say on that as well. The obvious thing you could think is, “Well, if I have the money and budget, what is wrong with methylfolate?” The simple answer right now is that we have heaps of research on one thing. We do not have heaps of research on this. It might be completely fine. We are just not at the same evidence base yet.
Torwen:
Absolutely. Moving on to the next one then, iron. Iron is another important fertility nutrient. It supports thyroid function, red blood cell production, and healthy cell replication. Women of reproductive age are at a consistently higher risk of iron deficiency. This is due to monthly blood loss with their period.
So it is super important to get your ferritin levels tested. That is your iron stores. This helps to see how much iron you have and whether supplementation will help. A specific 2025 study from a fertility clinic in Helsinki followed 292 women with infertility and iron deficiency. They received IV iron infusion, and it made a big difference. Live birth rates improved quite meaningfully following that treatment of their iron deficiency. It clearly supports fertility outcomes.
Aidan:
Yeah, so from a fertility perspective, it seems to help, which is great. Another angle is although we’re not talking about pregnancy, we are talking about prior to that. I think it is doubly important to have good ferritin stores at baseline. That is because iron needs get so much higher during pregnancy. Typically, 30 micrograms per litre of ferritin is considered the normal cut-off to avoid deficiency. Another safer target is being at least 50.
The next one we’re going to talk about is omega-3. Omega-3 has evidence for helping with ovulation and regular cycles for those with PCOS. That is relevant here as well. When looking at research on IVF, improved IVF outcomes are found in those with higher omega-3 status. There is also a lot of evidence for it helping the baby as well. Beyond just fertility, it can reduce the risk of preterm births by around 11% for 37 weeks.
It can reduce the risk by about 42% for 34 weeks. So it is a big improvement there. It helps with brain development as well. There are a few other pregnancy risks and post-pregnancy risks as well. It can reduce the risk of pre-eclampsia. It can also reduce the risk of postpartum depression. So I think it makes sense to start at a good baseline prior to pregnancy as well.
Torwen:
Not even to mention that omega-3s are also well documented for their anti-inflammatory effects. This is relevant if you do have conditions like PCOS and endometriosis. If you’re wanting to get pregnant, it can help with improving that low-grade chronic inflammation.
This is why an omega-3-rich diet makes a big difference too. Specifically, recommendations for pregnancy are 200 to 300 milligrams of DHA omega-3. If you’re eating oily fish two to three times a week, you’re likely meeting this from your diet. That includes salmon, sardines, mackerel, and anchovies. But if not, you’ll often see that it is added into prenatal supplements as well.
Aidan:
Now, talking about vitamin D as a common theme amongst a lot of our podcasts. Vitamin D is associated with a lot of things. Going back to PCOS, it is estimated that around 67 to 85% of women with PCOS have low vitamin D. Before I go on a tangent, the tangent was that this has recently been updated to PMOS. There is about a three-year transition period before that is officially done. So I’ll have to make a decision on what I call it.
But I’m going to go with PMOS for now. Outside of PMOS, for fertility specifically, the most compelling mechanistic evidence is implantation. Vitamin D regulates the genes that control the implantation window. When vitamin D is lower, on average, the uterine lining is thinner. There are also lower implantation rates. In IVF populations, a meta-analysis found that people with high vitamin D had around 33% higher odds of pregnancy.
Similar to a lot of other areas, there are a lot of associations. It is more so than comparing two groups directly. That would mean getting a group of people with low vitamin D. Then you would supplement them versus placebo and see what happens. But given what we know, I do not think it makes sense to do heaps of that research. You would identify people who are low in vitamin D and choose not to address that. I think it makes sense to just address that.
Torwen:
Yep. Vitamin D deficiency is something that is extremely common. It is also quite easy to fix. So, specifically for fertility-focused research, they suggest pushing your serum vitamin D above 100 nanomoles per litre. This is tested by the 25-hydroxy vitamin D test. That might be beneficial. So if you’re deficient, supplementing with 1000 to 2000 units of vitamin D3 is common.
Aidan:
We’re going to talk about other nutrients now. We won’t go as in-depth on these ones. That is because the evidence base is quite large for those other ones. But I’m going to start with B12. High folate with low B12 can cause issues with homocysteine. We have already touched on this a little bit with that methylfolate thing. So staying on top of that matters even more. The combo of low B12 also contributes with folate. Sorry, it also contributes to issues or risk with fertility and miscarriages as well.
Torwen:
For sure. It is especially more important if you’re following a plant-based diet. Next one is vitamin C. Vitamin C is a very potent antioxidant. It also plays a practical role in iron absorption. If you’re not eating lots of colourful fruit and veg, it makes sense to supplement with a bit of vitamin C too.
Aidan:
Yeah, and it is super easy to get that one as well. So easy. Choline. Choline also works alongside folate for neural tube development. It also helps with brain development. I think this is an area where the evidence seems to have outpaced what is in products. Heaps of prenatals still have low or no choline. But the evidence does seem to show that statistically, it helps quite a bit.
Torwen:
For sure. Selenium is another one that supports thyroid function. We know it is important, given that the thyroid plays a role in hormone regulation. Of course, it also plays a role in fertility. Brazil nuts are a super concentrated dietary source. One or two a day is typically sufficient to meet requirements.
Aidan:
I looked into some stats because I was curious. It looks like about 10% of women on fertility journeys have subclinical hypothyroidism. Two to four percent have diagnosed hypothyroidism. So this would be quite relevant for them. Selenium deficiency is quite rare in Australia. But what we would call suboptimal levels is pretty common. So there is a decent percentage of people where that is still relevant.
Zinc plays a role in most steps of reproduction. In the prep for this podcast, I was going to come up with the specifics. But it just got incredibly long. So, most steps of reproduction. Low zinc is also associated with irregular cycles, poor egg quality, and increased miscarriage risk.
Torwen:
For sure. CoQ10 is another one that we had on our list. I have only seen it get more attention in terms of older women trying to conceive. The reason behind this is that CoQ10 is involved in mitochondrial energy production within eggs. This specific function declines with age. So we still do need a bit more evidence in general population studies. But potentially, this is something you would consider if you were a bit more mature and trying to get pregnant.
Aidan:
And in the research, they are using dosages of 400 to 600 milligrams per day. That is a bit higher than the standard supplement dosage. In terms of when it is used, it is usually used throughout that entire 90-day window as well. Now we’re going to talk about some practical recommendations here.
I’m going to start in terms of my practical recommendations. The first one is I’d recommend a good quality diet in general. Obviously, there is heaps of non-nutrient, dietary pattern type stuff that does matter. But from a nutrient perspective, I really encourage a good quality diet to cover your bases.
I also, in almost all cases, will recommend supplementing on top of that. I personally will go with a prenatal for most people that covers the majority of these nutrients. Then I would add things that cover the gaps. For example, most prenatals won’t have good amounts of omega-3. So I’d consider adding that as well. I’d also consider CoQ10 in relevant cases too.
Torwen:
I’m with you on that. My next practical recommendation, and this will be something you do if you work with a dietitian. Getting that baseline blood work done. Check your ferritin levels, vitamin D, B12, and all that sort of thing. This makes sure we can address any deficiencies along with supplementing for that baseline.
Aidan:
We had a section on misconceptions. Did you have misconceptions?
Torwen:
Not many.
Aidan:
All I had was the opposite of what I just said. One common misconception is that eating well means supplements won’t be needed. The reason I’d say that is a misconception is that it is sometimes hard to get enough of those things. For example, the logistics of getting enough iron are really hard, particularly once pregnancy starts.
It is also hard to get to a good baseline prior to that as well. Folate is also hard to get to those numbers too. There are many numbers that people will fall short of. That is unless they are actively tracking every single step of the process.
Torwen:
My only other little misconception was around specific conditions. If you have PCOS, endometriosis, hypothyroidism, or a history of miscarriage, check with a GP or dietitian. This is where a more personalised approach might be warranted for you.
Aidan:
Cool. Well, we’ll wrap up there. This has been episode 260. Hopefully some of this has been helpful in some way, shape, or form. But as always, if you haven’t already, please leave a rating or a review. We would massively appreciate that.