Navigating the world of fertility supplements can feel overwhelming. With so many options available, it’s often difficult to distinguish between marketing hype and evidence-based nutritional therapy. One supplement that consistently appears in fertility discussions is myo-inositol. Recommended for its potential to enhance egg quality and improve reproductive outcomes, it’s worth taking a closer look at the science behind this powerful nutrient.

This guide will break down what myo-inositol is, how it works, who might benefit from it, and what you should consider before adding it to your routine.

What is myo-inositol?

Myo-inositol, often referred to simply as inositol, is a type of sugar alcohol that is structurally similar to B-vitamins. It is a crucial component of cell membranes and plays a significant role in cell signalling, which is essential for numerous biological processes, including follicular development and reproduction. In addition, inositols can have insulin-like properties, meaning they could help improve insulin sensitivity (notable, for example, for people with PCOS).

The science: how does myo-inositol support fertility?

The effectiveness of myo-inositol in fertility therapy is directly linked to its presence and function within the ovarian environment. Research shows that when myo-inositol is found in the follicular fluid, (the fluid that surrounds and nourishes the developing egg), it has a positive impact on fertility markers [1].

Key mechanisms include:

Improved egg development: Myo-inositol in the follicular fluid is associated with better overall oocyte (egg) development [1].
Enhanced egg quality: Its presence is a key factor in supporting the quality of the mature egg, which is critical for successful fertilisation and embryo development [1].
Higher fertilisation rates: Studies suggest that adequate levels of myo-inositol in the follicular fluid are linked to improved fertilisation rates, a crucial step on the path to pregnancy [1].
Reduced amount of stimulation drugs: evidence suggest that myo-inositol’s working could help reduce the amount of drugs required for stimulation and the risk of ovarian hyperstimulation syndrome [2].

Furthermore, myo-inositol is often used in combination with other supplements during assisted reproductive technology (ART) cycles. Research has shown that a supplement regimen including myo-inositol can improve oocyte quality in women who previously had poor outcomes in in vitro fertilisation (IVF) cycles [3]. Another study highlighted the positive effects on oocyte quality and pregnancy outcomes when myo-inositol was combined with melatonin and folic acid during IVF [4].

Who Can Benefit from Myo-Inositol?

Based on the scientific evidence, myo-inositol supplementation may be particularly beneficial for:

Women seeking to improve egg quality: For anyone looking to support their reproductive health, myo-inositol can play a role in fostering a healthy follicular environment to support egg development [1].
Women undergoing IVF: It is frequently recommended for women undergoing ART, especially those with a history of poor oocyte quality in previous cycles [5].
Women with polycystic ovary syndrome (PCOS): While the provided sources focus on its general impact on egg quality, myo-inositol is one of the most well-researched supplements for women with PCOS. It is known to help improve insulin sensitivity, regulate menstrual cycles, and promote ovulation in this population [6].
Male infertility: It may improve sperm quality and overall male fertility [7].

What to expect and other considerations

If you are considering myo-inositol, it's important to understand the practical aspects of supplementation.

Dosage: The dose most frequently used in research studies is between 2,000 and 4,000 mg per day. It is typically sold in powder or capsule form [1].
Combination with Other Supplements: As the research indicates, myo-inositol is often part of a broader fertility-support protocol that may include folate and other antioxidants. This synergistic approach can offer more comprehensive support for reproductive health [4,5]
Consult a Healthcare Professional: Before beginning any new supplement regimen, especially when trying to conceive, it is essential to speak with your doctor or a qualified healthcare provider. They can help you determine if myo-inositol is right for your specific situation and recommend an appropriate dosage and protocol.

The takeaway

Myo-inositol is more than just another supplement; it is a research-backed tool that can meaningfully support female fertility by improving the very environment in which eggs develop. Its role in enhancing oocyte quality and fertilisation rates makes it a valuable consideration for women on their conception journey, particularly those undergoing IVF or managing conditions like PCOS.

By understanding the science and working with a trusted healthcare provider, you can determine if myo-inositol is a fitting addition to your nutritional strategy for achieving your fertility goals.

Just remember, there is no magic supplement or food that will magically help you get pregnant. Our health is influenced by a huge variety of factors, some in and some out of our control. If you want to dive deeper and discuss actions you can take to improve your health and fertility, don’t hesitate to book in for a consultation for one-on-one support.

References

[1] Russo, M., Forte, G., Montanino Oliva, M., Laganà, A. S., & Unfer, V. (2021). Melatonin and Myo-Inositol: Supporting Reproduction from the Oocyte to Birth. International journal of molecular sciences, 22(16), 8433. https://doi.org/10.3390/ijms22168433

[2] Laganà, A. S., Vitagliano, A., Noventa, M., Ambrosini, G., & D'Anna, R. (2018). Myo-inositol supplementation reduces the amount of gonadotropins and length of ovarian stimulation in women undergoing IVF: a systematic review and meta-analysis of randomized controlled trials. Archives of gynecology and obstetrics, 298(4), 675–684. https://doi.org/10.1007/s00404-018-4861-y

[3] Zhang, J., Zhang, H., Zhou, W., Jiang, M., & Lin, X. (2025). Effect of myo-inositol supplementation in mixed ovarian response IVF cohort: a systematic review and meta-analysis. Frontiers in endocrinology, 16, 1520362. https://doi.org/10.3389/fendo.2025.1520362

[4] Rizzo, P., Raffone, E., & Benedetto, V. (2010). Effect of the treatment with myo-inositol plus folic acid plus melatonin in comparison with a treatment with myo-inositol plus folic acid on oocyte quality and pregnancy outcome in IVF cycles. A prospective, clinical trial. European Review for Medical and Pharmacological Sciences, 14(6), 555–561.

[5] Unfer, V., Raffone, E., Rizzo, P., & Buffo, S. (2011). Effect of a supplementation with myo-inositol plus melatonin on oocyte quality in women who failed to conceive in previous in vitro fertilization cycles for poor oocyte quality: A prospective, longitudinal, cohort study. Gynecological Endocrinology, 27(11), 857–861. https://doi.org/10.3109/09513590.2011.564687

[6] Merviel, P., James, P., Bouée, S. et al. Impact of myo-inositol treatment in women with polycystic ovary syndrome in assisted reproductive technologies. Reprod Health 18, 13 (2021). https://doi.org/10.1186/s12978-021-01073-3

[7] Vazquez-Levin, M. H., & Verón, G. L. (2020). Myo-inositol in health and disease: its impact on semen parameters and male fertility. Andrology, 8(2), 277–298. https://doi.org/10.1111/andr.12718

Should you take myo-inositol when trying to conceive?