Educational guide

Study links low oxytocin levels to symptoms of polycystic ovary syndrome

In a recent systematic review published in Current Issues in Molecular Biology, researchers from Portugal examined and discussed the role of oxytocin (OT) in polycystic ovary syndrome (PCOS), its association with PCOS symptoms, and the effect of OT administrat

Written by Peptide Therapy Guide Editorial TeamPublished September 2, 2026

For education only

This guide cannot diagnose a condition or recommend a personal treatment plan. Discuss medical questions with a qualified professional.

They found that PCOS is associated with reduced serum OT levels, and alterations in OT levels are linked to fertility issues and body weight, suggesting a potential role of OT dysfunction in the development of PCOS.

Background

PCOS is a complex and prevalent endocrine disorder in women of reproductive age that affects their quality of life. It is characterized by polycystic ovaries, androgen excess, and ovulatory dysfunction, often leading to infertility and various metabolic, reproductive, and psychological issues.

PCOS is linked to high levels of androgen and abnormal LH/FSH (luteinizing hormone/ follicle-stimulating hormone) ratios, contributing to anovulatory infertility and increased risks during pregnancy.

Biochemically, OT is a nine-amino acid-long peptide involved in cognitive, emotional, and reproductive functions. While it is generated in the hypothalamus and secreted by the posterior pituitary gland, OT receptors (OXTR) are found in various body parts, including the ovaries and prostate gland.

OT is vital for various reproductive and behavioral functions in humans, including pregnancy, parturition, breastfeeding, bonding, prosocial behavior, decision-making, physical activity, and orgasm.

Previous studies suggest that OT levels are lower in women with PCOS, potentially impacting mood and weight. Animal studies indicate OT deficiency can potentially lead to obesity, and OT administration may reduce weight and enhance muscle tone.

Despite these findings, the exact role of OT in PCOS remains unclear. In the present systematic review, researchers aimed to clarify OT's role in PCOS by examining all the relevant animal and human studies.

Specifically, it focused on (i) identifying potential alterations in basal plasma OT levels in PCOS, (ii) understanding how changes in OT levels might relate to PCOS symptoms, and (iii) investigating the effects of OT administration on PCOS.

About the study

Databases, including PubMed, Scopus, and Web of Science, were thoroughly searched to identify relevant studies. The review involved eight studies, including experimental studies, randomized clinical trials, clinical pilot studies, case-control studies, and population genetics studies.

Five of the included studies were conducted on humans (n = 609 women), while three were conducted on animals. It excluded studies on other endocrine diseases, male studies, reviews, and meta-analyses.

Results and discussion

Cohen’s kappa value was found to be 0.742, indicating significant agreement between the two individual reviewers. The human studies primarily explored the relationship between OT administration and fertility.

Two clinical trials found that intranasal OT did not improve fertility in PCOS patients, possibly due to inadequate dosing or administration methods.

These studies did not measure blood or salivary OT levels. One study found lower OT levels in PCOS patients compared to non-PCOS controls and linked these lower levels to hormonal imbalances in the hypothalamic-pituitary–ovarian (HPO) axis.

A case-control study also associated higher OT levels with improved pregnancy rates in PCOS women. One genetic study examined the gene polymorphisms in OXTR in PCOS patients and found five variants linked to PCOS, suggesting a genetic influence on OXTR expression.

The animal studies used rat models to assess the effects of OT on metabolic disorders and uterine function. One study found that OT administration regulated uterine contractions in PCOS rats, while another reported that acute OT administration could reduce body weight and food intake in PCOS rats.

Chronic OT administration was found to decrease food intake and body weight in both PCOS and control rats. Another study found that OT administration reduced body weight, visceral fat, and adipocyte size in a dihydrotestosterone (DHT)-induced rat PCOS model.

Overall, these findings suggest that OT may influence the metabolic and reproductive functions in PCOS, but further research is warranted to understand its therapeutic potential.

Further, the review highlighted gaps in the current research in the field, such as the need for studies assessing the impact of OT on prosocial behavior, couple relationships, and sexual satisfaction in PCOS.

Different dosage regimens and patterns of OT administration were also found to be insufficiently studied, highlighting the need for further research.

Conclusion

In conclusion, the present review comprehensively examined the studies exploring the effect of OT levels or OT administration on PCOS. Most studies emphasized OT's role in fertility issues, with only one study linking higher OT levels to increased pregnancy rates.

Consistently, basal OT levels were found to be reduced in PCOS women, suggesting that low OT, alongside low FSH levels, contributes to anovulation in PCOS.

Additionally, potential molecular mechanisms involving altered OXTRs and genetic variants in PCOS were discussed. These insights are crucial for potentially developing targeted treatments and improving the quality of life for women with PCOS in the future.

Cera N. et al., (2024) The Role of Oxytocin in Polycystic Ovary Syndrome: A Systematic Review. Current Issues in Molecular Biology,. doi:https://doi.org/10.3390/cimb46060313. https://www.mdpi.com/1467-3045/46/6/313

Connected reading

Helpful context for this guide

Source-derived material selected through this article’s indexed topics.

Related questions

01What is oxytocin, and what is it used for?

Oxytocin used as medication is a synthetic form of the natural human hormone oxytocin produced by the hypothalamus region in the brain and secreted into the bloodstream by the pituitary gland. Oxytocin is used to induce or improve uterine contractions during delivery and to prevent uncontrolled bleeding (hemorrhage) after the delivery. Oxytocin may also be used to eliminate the uterine contents after a spontaneous or induced termination of pregnancy. Oxytocin is naturally secreted by the body to produce uterine contractions during childbirth, and synthetic oxytocin works likewise. Oxytocin works on positive feedback. The release of oxytocin causes uterine contractions, which in turn, cause more oxytocin to be released, increasing the intensity and frequency of contractions, enabling a vaginal delivery. Oxytocin binds to oxytocin receptors in the uterine muscle wall (myometrium) and stimulates contraction by increasing influx of calcium ions in the uterine muscle cells. Oxytocin receptor concentration normally increases during pregnancy, with levels peaking at term when labor starts. The response to oxytocin varies between individuals depending on the concentration of oxytocin receptors in the uterus. Oxytocin also causes contraction of the myoepithelial cells in the breasts, which helps eject the milk out. The baby’s attempt to suck sends positive feedback, which in turn stimulates oxytocin release and milk output. Oxytocin also has antidiuretic and vasodilatory effects, increasing fluid balance and improving blood flow. In the brain, oxytocin acts as a neurotransmitter and plays an important role in human behaviors including romantic attachment, sexual arousal, trust, mother-child and other relationship bonding. Oxytocin is approved for use in induction of labor in pregnant women at term or near term in certain circumstances:

Source: www.medicinenet.com ↗

02Are Humans Naturally Monogamous?

Current evidence suggests that humans possess a biological capacity to form stable emotional bonds, but neither biology nor culture alone determines relationship patterns. Instead, evidence suggests that human monogamy emerges through interactions among biological predispositions, social norms, cultural expectations, economic circumstances, and historical context. Rather than representing either an inherent human characteristic or a purely cultural invention, monogamy is increasingly understood as one of several flexible relationship strategies shaped by both biology and the environment. This article was translated from El Médico Interactivo , part of the Medscape Professional Network.

Source: www.medscape.com ↗

Research context

Read sources and limitations before applying a claim.

Human & Animal Studies

Human Studies Oxytocin is among the most extensively studied peptide hormones in medicine. Human studies have evaluated oxytocin for: Labor induction Labor augmentation Postpartum hemorrhage Breastfeeding physiology Schizophrenia Social cognition Chronic pain Obesity Eating disorders Obstetric studies have firmly established the efficacy of oxytocin for labor induction and postpartum hemorrhage management, leading to FDA approval. Research involving intranasal oxytocin for psychiatric and neurologic disorders has demonstrated mixed results, with some studies showing improvements in social cognition or emotional processing while others have found limited or inconsistent benefit. Additional large randomized trials are ongoing. Animal & Preclinical Studies Animal studies have demonstrated that oxytocin: Regulates maternal behavior Promotes pair bonding Modulates stress responses Influences social recognition Regulates appetite Alters pain perception Supports wound healing Influences cardiovascular function Modulates immune responses These findings have provided the biologic rationale for investigating oxytocin in numerous human diseases beyond its established obstetric uses.

Source: r2medicalclinic.com ↗

Practical and safety references

These excerpts are educational, not personalised medical instructions.

Dosage reference

Dosages

Oxytocin is administered under medical supervision, with dosages tailored to specific clinical needs and patient conditions. For labor induction, Oxytocin is typically given intravenously using an infusion pump, starting at a low rate of 0.5 to 2 milliunits per minute, gradually increased by 1 to 2 milliunits per minute every 30 to 60 minutes until effective contractions are achieved. The total dose rarely exceeds 20 milliunits per minute to avoid overstimulation of the uterus. In biohacking circles, there are reports that Oxytocin is used in the range of 30-80mcg as needed, via injections and intranasal spray.

Source: exploring-peptides.com ↗

About the author

Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

View all articles →