How N-acetylcysteine (NAC) can help with polycystic ovarian syndrome (PCOS)

PCOS symbol


N-acetylcysteine (NAC) is a molecule few people have even heard of, but is incredibly valuable when it comes to natural health support. It is in fact an altered and more stable form of the amino acid cysteine. Cysteine itself is present in most high protein foods such as meat, fish and dairy products. Vegans get most of their cysteine from plant sources such as granola and oat flakes, as well as vegetables like broccoli, red pepper and onion.
As a supplement, the more stable NAC is both safe and inexpensive, and has been commercially available for a long time. It’s also generally well-tolerated.
Its importance stems from the fact that it is a precursor for endogenous glutathione biosynthesis. The body converts NAC to cysteine, which is then converted to glutathione. Glutathione is one of the body’s main antioxidants, helping to reduce free radical damage and playing a role in detoxification. Not surprisingly, NAC has been shown to support general health in many respects, ranging from heart to mental health issues. While its benefits have been explored for many realms of health, studies on its role in fertility in general and polycystic ovarian syndrome (PCOS), which is a major reason for female subfertility, specifically, are rather recent.

NAC and fertility

A number of studies have demonstrated the benefits of NAC supplementation for fertility in both men and women. In men, NAC has been shown to improve sperm quality in subfertile men. In women, research has revealed significant benefits for endometriosis patients and patients suffering from recurrent pregnancy loss.


Interestingly, general research on NAC has revealed a role in insulin sensitivity. The terms insulin sensitivity and its opposite insulin resistance describe the way body cells respond to our blood sugar hormone insulin. Due to the fact that insulin not only regulates blood sugar levels, but also certain aspects of our endocrine system, scientists were soon wondering whether it might be an interesting natural treatment option for patients with PCOS as well.

NAC ameliorates metabolic and endocrine characteristics of women with polycystic ovary syndrome (PCOS)

Researchers did not have to wonder for long: In a randomized double-blind clinical trial on 94 women with diagnosis of PCOS without additional complications, oral treatment with NAC for 24 weeks resulted in significant improvements of metabolic parameters. Specifically, lipid profile and fasting blood sugar (FBS) as well as fasting blood insulin was much improved after treatment.
In a meta-analysis of 18 studies, including 2,185 participants, NAC significantly reduced total testosterone levels and increased FSH levels.

NAC improves ovulation

Frequent symptoms of polycystic ovarian syndrome include irregular or missing ovulations. Current medication to improve this are often accompanied by side effects and do not work for every woman.
Analysis of eight studies with a total of 910 women with PCOS showed that treatment of PCOS patients with NAC could significantly improve ovulation as compared to placebo. In addition to that, higher odds of having a live birth and getting pregnant in the first place were recorded.

NAC improves oocyte quality

These latter observations may find their explanation in the results of a rather recent study which found that NAC treatments of PCOS patients can improve egg quality. This is particularly important if you are going through IVF treatments or are trying to get pregnant when you are older than 35. In the study of women suffering from PCOS, the group who received a NAC supplement saw a decrease in the amount of abnormal ovarian cells and a significant increase in embryo quality .

Supplementing NAC

NAC is widely available as an oral dietary supplement and is relatively inexpensive.
If you are currently taking an antidepressant or undergoing cancer treatment, be sure to discuss the use of NAC with your physician, as it may interact with some antidepressants and chemotherapy. Other than that, it is virtually free of side effects when taken in moderate dosages of no more than a few hundred mg daily.
In combination with other micronutrients important for PCOS patients, NAC is available as part of Fertilovit F PCOS. This is a formula designed to dietetically support women with PCOS who are planning for pregnancy.


Amin AF, Shaaban OM, Bediawy MA. N-acetyl cysteine for treatment of recurrent unexplained pregnancy loss. Reprod Biomed Online. 2008 Nov;17(5):722-6.

Amini L, Tehranian N, Movahedin M, Ramezani Tehrani F, Ziaee S. Antioxidants and management of polycystic ovary syndrome in Iran: A systematic review of clinical trials. Iran J Reprod Med. 2015 Jan;13(1):1-8.

Badawy A, State O, Abdelgawad S. N-Acetyl cysteine and clomiphene citrate for induction of ovulation in polycystic ovary syndrome: a cross-over trial. Acta Obstet Gynecol Scand. 2007;86(2):218-22.

Bashan N, Kovsan J, Kachko I, Ovadia H, Rudich A.Positive and negative regulation of insulin signaling by reactive oxygen and nitrogen species. Physiol Rev. 2009 Jan;89(1):27-71. doi: 10.1152/physrev.00014.2008.

Cheraghi E, Mehranjani MS, Shariatzadeh MA, Esfahani MH, Ebrahimi Z. N-Acetylcysteine improves oocyte and embryo quality in polycystic ovary syndrome patients undergoing intracytoplasmic sperm injection: an alternative to metformin. Reprod Fertil Dev. 2016 Apr;28(6):723-31. doi: 10.1071/RD14182.

Cheraghi E, Soleimani Mehranjani M, Shariatzadeh SMA, Nasr Esfahani MH, Alani B. N-Acetylcysteine Compared to Metformin, Improves The Expression Profile of Growth Differentiation Factor-9 and Receptor Tyrosine Kinase c-Kit in The Oocytes of Patients with Polycystic Ovarian Syndrome. Int J Fertil Steril. 2018 Jan;11(4):270-278. doi: 10.22074/ijfs.2018.5142. Epub 2017 Oct 12.

Ciftci H, Verit A, Savas M, Yeni E, Erel O. Effects of N-acetylcysteine on semen parameters and oxidative/antioxidant status. Urology. 2009 Jul;74(1):73-6. doi: 10.1016/j.urology.2009.02.034. Epub 2009 May 9.

Javanmanesh F, Kashanian M, Rahimi M, Sheikhansari N. A comparison between the effects of metformin and N-acetyl cysteine (NAC) on some metabolic and endocrine characteristics of women with polycystic ovary syndrome. Gynecol Endocrinol. 2016;32(4):285-9. doi: 10.3109/09513590.2015.1115974. Epub 2015 Dec 10.

Mokhtari V, Afsharian P, Shahhoseini M, Kalantar SM, Moini A. A Review on Various Uses of N-Acetyl Cysteine. Cell J. 2017 Apr-Jun;19(1):11-17. Epub 2016 Dec 21.

Nemati M, Nemati S, Taheri AM, Heidari B. Comparison of metformin and N-acetyl cysteine, as an adjuvant to clomiphene citrate, in clomiphene-resistant women with polycystic ovary syndrome. J Gynecol Obstet Hum Reprod. 2017 Sep;46(7):579-585. doi: 10.1016/j.jogoh.2017.07.004. Epub 2017 Jul 8.

Porpora MG, Brunelli R, Costa G, Imperiale L, Krasnowska EK, Lundeberg T, Nofroni I, Piccioni MG, Pittaluga E, Ticino A, Parasassi T. A promise in the treatment of endometriosis: an observational cohort study on ovarian endometrioma reduction by N-acetylcysteine. Evid Based Complement Alternat Med. 2013;2013:240702. doi: 10.1155/2013/240702. Epub 2013 May 7.

Shahveghar Asl Z, Parastouei K, Eskandari E. The effects of N-acetylcysteine on ovulation and sex hormones profile in women with polycystic ovary syndrome: A systematic review and meta-analysis. Br J Nutr. 2023 Jan 4:1-28. doi: 10.1017/S0007114522003270. Epub ahead of print. PMID: 36597797.

Thakker D, Raval A, Patel I, Walia R. N-acetylcysteine for polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled clinical trials. Obstet Gynecol Int. 2015;2015:817849. doi: 10.1155/2015/817849. Epub 2015 Jan 8.

About the author

Dr. rer. nat. Birgit Wogatzky

For many years now, biologist and nutritionist Dr Birgit Wogatzky, has been focusing on the special needs of fertility patients. For the readers of this blog, she sums up interesting novel information and developments from current research projects regarding lifestyle and nutrition of fertility patients.

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