An Evidence-Based Guide to Supporting Your Fertility

The purpose of preconception care is to give your body the best foundations for a healthy pregnancy. I have written a lot about preconception care in the past few years! Information about what this should look like, what to eat, and how long to commit to it can be found here, and what nutrients to focus on, prenatal supplements, pathology testing, and nervous system considerations here. I do suggest reading these before diving into this blog. Here we will explore six evidence-backed supplements that can support your reproductive health journey - CoEnzymeQ10 (CoQ10), Fish oil (EPA/DHA,) N-Acetyl Cysteine (NAC), melatonin, inositol, and Nicotinamide Riboside Chloride (NRC).

CoQ10: Protecting Eggs and Mitochondrial Energy

CoQ10, or Coenzyme Q10, is an antioxidant that keeps your cells fuelled with energy. This is crucial for your oocytes, which depend on healthy functioning mitochondria to thrive. As we age, oxidative stress can diminish egg quality, making it harder to conceive. CoQ10 helps shield eggs from damage, and research suggests it can improve ovarian response and pregnancy outcomes.

The evidence is robust! A 2018 study in Human Reproduction found that women taking 200 to 600 mg of CoQ10 daily before IVF had better egg quality and higher pregnancy rates. A 2017 study in the Journal of Assisted Reproduction and Genetics showed that 600 mg daily boosted the number of mature eggs retrieved in women over 35 during fertility treatments. And in 2020, Reproductive Biology and Endocrinology reported that 400 mg daily reduced oxidative stress in follicular fluid, supporting healthier eggs.

To supplement you want to make sure that the form is ubiquinol, dosing from 200 - 600mg daily. The exact amount necessary for you will depend on your individual needs and circumstances (which goes for all supplements in this article - sorry to sound like a broken record here)! Start at least 3 months before trying to conceive, freezing eggs/embryos, or IVF to give it time to work. CoQ10 is a key consideration if you’re over 35 or feel your egg quality needs specific support.

Fish Oil: Easing Inflammation and Supporting Implantation

Fish oil delivers omega-3 fatty acids - EPA and DHA - which are fantastic for reducing inflammation. It also improves blood flow to your reproductive organs, which can mean a healthier uterine lining and better chances of implantation. Plus, omega-3s are vital for your bub’s brain development, making it essential during preconception!

Studies back this up. A 2020 paper in Fertility & Sterility found that women taking 1000 mg of EPA and DHA daily had better embryo quality and implantation rates during IVF. In 2018, The Journal of Clinical Endocrinology & Metabolism showed that 1200 mg daily improved menstrual regularity and reduced inflammation in women with PCOS. And a 2019 study in Nutrients noted that 1000 mg daily cut inflammatory markers in women with endometriosis, creating a better environment for conception.

Aim for 1-2g of combined EPA and DHA daily, and choose a high-quality fish oil that has been third-party tested. Omega-3s are a non-negotiable part of all of my preconception protocols for clients. If you are vegan, I suggest supplementing with the microalgae schizochytrium sp.

NAC: An Antioxidant and Inflammation Ally

N-acetylcysteine, or NAC, is the precursor to the master antioxidant in our bodies, glutathione. NAC improves egg quality, can increase implantation and pregnancy rates, and has the ability to regulate ovulation by reducing insulin. This supplement is a standout if you have endometriosis, PCOS, or another inflammatory health condition.

A 2021 study in Reproductive Sciences found that 600 to 1800 mg daily reduced endometriosis-related pain and improved fertility outcomes. A 2015 paper in the European Journal of Obstetrics & Gynecology and Reproductive Biology showed that 1200 mg daily for 3 months supporting ovulation rates in women with PCOS, matching metformin’s effects. And in 2019, the Journal of Minimally Invasive Gynecology linked 600 mg daily to lower oxidative stress in endometriosis patients.

NAC dosing is very person-dependant, ranging from 600 - 1800 mg daily, best taken in split doses. My hot tip - this compound tastes pretty average, so opt for capsules or a flavoured option if you can!

Melatonin: Sleep and Reduce Oxidative Damage

Melatonin is a hormone that your body produces naturally towards night time, with levels peaking around 3 - 5 hours after its onset. It is a potent antioxidant which can protect your eggs from oxidative damage, improving egg quality and IVF outcomes. I work alongside my clients healthcare teams, and have found in recent years that gynaecologists are using melatonin more and more as part of their prescribed treatment plan for IVF.

A 2017 study in the Journal of Ovarian Research found that 3 mg nightly during IVF cycles improved egg quality and conception rates. A 2014 paper in Gynecological Endocrinology showed 3 mg daily improved oocyte quality in women with past IVF struggles. And in 2020, Antioxidants reported that 2 mg nightly reduced oxidative stress in follicular fluid.

The studied dose tends to sit around 1 to 3 mg, 30 - 60 minutes before bed. If stress, poor sleep, or IVF are part of your journey, melatonin may be worth considering.

Inositol: Restoring Ovulation and Supporting Insulin

Inositol is brilliant for improving insulin sensitivity, regulating cycles, and supporting ovulation. It’s an essential compound for women with PCOS, who have elevated androgens and/or insulin levels. It supports egg quality while increases pregnancy outcomes.

A 2017 study in Gynecological Endocrinology found that 4 g daily improved ovulation and pregnancy rates in PCOS patients. In 2019, the International Journal of Endocrinology showed 2 g twice daily (with 400 mcg folic acid) resulted in regular cycles for 70% of PCOS women in 3 months. And a 2020 study in the European Review for Medical and Pharmacological Sciences showed that 4 g daily had strong insulin and ovulation benefits.

As you can see most studied doses are 4 g daily, I always prescribe inositol into split doses to mitigate gastrointestinal side effects. If you have irregular cycles, elevated androgens, or insulin resistance, inositol is a key compound for you to consider, regardless of whether you are TTC or not.

NRC: Energising Your Cells

Nicotinamide Riboside Chloride, or NRC, is a form of vitamin B3 that boosts NAD+, a coenzyme linked to cellular energy, DNA repair, and mitochondrial health. This is key for egg quality, which declines as we age, and can be further perpetuated by stress, energy output, and antioxidant availability.

It’s important to note that human studies are still emerging on NRC. At this stage we mostly have animal studies to analyse, but the research is promising. A 2016 animal study in Cell Metabolism showed NRC improved egg quality in ageing mice by raising NAD+ and mitochondrial function. A 2021 human study in Nature Communications found 500 mg daily increased NAD+ levels in healthy adults, suggesting potential fertility perks. And a 2019 study in Aging Cell saw older mice regain ovarian function with NRC.

NRC dosing sits from 250 - 500 mg daily. It’s worth considering if you’re low on energy or want to support egg health as you age. The current studies are strong and I’m excited to see what we find in human studies in the future!

Safety and Practical Tips

Before starting any supplement, check with your healthcare provider, especially if you’re TTC, on medication, or have a health condition like PCOS or endometriosis. Quality is important, opt for third-party tested products to ensure purity and avoid contaminants. Timing and dose also matters - you want to be taking most supplements after meals to improve absorption, and for melatonin you need to take this at night.

It’s important to recognise that the compounds discussed here are not a panacea for your fertility, they cannot do all of the heavy lifting for you if the right dietary and lifestyle habits are not in place. For more information about the foundational aspects of preconception care when TTC, please see my blogs on this topic - Part 1 and Part 2. If you’re undergoing fertility treatment, let your specialist know about any supplements you’re taking to ensure they align with your protocol.

Please leave any questions you have below. And if you are TTC, undergoing fertility treatment, or thinking about preconception care and would like individualised support - bookings and enquiries into working with me can be made here.

Author
Jaclyn Cave
BHSc (Nat), BComm (Soc)
Masters Women’s Health Medicine (UNSW - completing)

References

All, BlogsJaclyn CaveMarch 31, 2025Comment