Stem Cells for PCOS: What a Clinical Trial Found About Fertility, Hormones, and Metabolic Health

A 2026 clinical trial tested stem cells in 40 women with PCOS, tracking effects on insulin resistance, hormones, and pregnancy rates over six months.

Could Stem Cells Help Women with PCOS?

If you have polycystic ovary syndrome — or know someone who does — you know how frustrating it can be to manage. Hormones all over the place, irregular periods, difficulty getting pregnant, and a metabolism that seems to work against you. Standard treatments help, but they don’t work for everyone.

That’s why a 2026 clinical trial from Indonesia caught attention in the medical research community. Researchers tested whether stem cells — specifically those derived from umbilical cord tissue — could improve metabolic health and reproductive outcomes in women with PCOS. Here’s what they found, in plain terms.

What Is PCOS, and Why Is It So Hard to Treat?

PCOS is one of the most common hormonal disorders in women of reproductive age. It involves a combination of irregular periods, elevated male hormones (which can cause acne and excess hair growth), and small fluid-filled sacs on the ovaries.

What makes PCOS particularly tricky is that it affects the whole body, not just the reproductive system. Between 40% and 70% of women with PCOS also have insulin resistance — meaning the body doesn’t respond properly to insulin. Over time, this raises the risk of type 2 diabetes, high blood pressure, and heart disease, while also making fertility problems worse.

The most commonly prescribed medication is metformin, which helps improve insulin sensitivity. But it doesn’t fully address the hormonal imbalance or the underlying inflammation that drives many PCOS symptoms. This gap in treatment is exactly what prompted researchers to explore stem cells as a potential alternative.

What Are UC-MSC Stem Cells, and How Might They Help?

Umbilical cord-derived mesenchymal stem cells — UC-MSCs for short — come from the tissue inside umbilical cords collected after birth. They are not embryonic stem cells, so they carry fewer ethical concerns and are generally well tolerated by the body.

What makes them scientifically interesting is their ability to reduce inflammation and send chemical signals that encourage healing and hormonal regulation. They also produce what researchers call a “secretome” — essentially a concentrated blend of growth factors and proteins that can influence how surrounding tissues behave, even without the stem cells themselves being present.

In animal studies, UC-MSCs showed early promise in improving hormonal balance and restoring ovarian function in PCOS models. The 2026 Indonesian trial was designed to find out whether those early results could translate to real patients.

How Was the Trial Conducted?

The study enrolled 40 women aged 20 to 40, all diagnosed with PCOS according to internationally recognized criteria. It took place at Gatot Soebroto Army Hospital in Jakarta, Indonesia, between 2022 and 2024, and the findings were published in February 2026 in the journal Gynecologic Oncology: Current Therapies and New Frontiers.

Participants were divided into four equal groups of ten and assigned to one of the following for 30 days, then monitored over six months:

• Metformin — the standard oral medication used in PCOS and diabetes management
• UC-MSC infusion — a single intravenous dose of umbilical cord stem cells
• Secretome nasal drops — the bioactive fluid produced by stem cells, delivered as drops into the nose daily for 30 days
• UC-MSC + Secretome combined — both the infusion and the nasal drops together

Researchers tracked key metabolic markers at months one, three, and six, including fasting blood sugar, insulin levels, a hormone called adiponectin, and C-peptide. They also monitored menstrual regularity, ovulation rates, and pregnancy outcomes throughout the observation period.

What Did the Results Show?

Metabolic Markers: A Mixed Picture

The metabolic findings were nuanced — and in some cases, surprising.

The UC-MSC-only group showed a notable increase in adiponectin by month six. Adiponectin is an important hormone that helps regulate insulin sensitivity and reduce inflammation. It is often abnormally low in women with PCOS, so an increase in this marker is considered a positive metabolic signal.

The secretome-only group, however, showed increases in fasting insulin, fasting blood sugar, and insulin resistance scores over time — an unexpected pattern. Researchers suggest this may be related to how the secretome’s complex mix of signalling molecules interacts with insulin pathways, but the exact mechanism is not yet understood. The intranasal delivery route also adds another layer of uncertainty that the study was not designed to fully resolve.

Metformin and UC-MSC monotherapy, by contrast, did not produce significant changes in fasting blood sugar or overall insulin resistance scores during the observation period.

Menstrual Regularity and Ovulation

Menstrual cycle improvement was highest in the metformin group at 80%, followed by the combined UC-MSC and secretome group at 70%. Ovulation rates told a slightly different story — the secretome-only group recorded the highest rate at 70%, followed by the UC-MSC group at 60%, while metformin and the combination group each came in at 50%.

Pregnancy Rates

The most discussed finding was the pregnancy rates recorded over the six-month period. The UC-MSC-only group reported the highest rate at 40%, with all confirmed pregnancies occurring after the six-month mark. The combined group followed at 30%, metformin at 20%, and the secretome-only group at 10%. Importantly, no serious side effects were reported in any group throughout the entire trial.

What Does This Mean for Women with PCOS?

It is important to be clear: this was a small exploratory study with just 10 women per group, and it was designed to generate questions and directions for future research — not to provide definitive treatment answers. The results are interesting, but they are not sufficient to change how PCOS is currently managed clinically.

What the study does offer is a starting point. It demonstrates that stem cell-based approaches in PCOS appear feasible, seem safe in the short term, and produce measurable biological changes worth exploring further. The higher pregnancy rates in the UC-MSC group are encouraging, but they need to be confirmed in larger, longer, and more rigorously designed trials before any firm conclusions can be drawn.

For now, metformin and other established treatments remain the recommended clinical standard. Women with PCOS should always work with qualified healthcare providers and avoid pursuing experimental stem cell therapies outside of properly approved clinical research settings.

The Bottom Line

A 2026 Indonesian clinical trial tested four approaches in 40 women with PCOS — metformin, UC-MSC stem cells, secretome drops, and a combination of the two. The stem cell group showed the highest pregnancy rate and a meaningful improvement in a key hormonal marker. The secretome-only group, however, produced some unexpected metabolic changes that researchers do not yet fully understand.

Science rarely moves in straight lines, and this study is best understood as a carefully designed early step in a developing field. With larger trials likely to follow, clearer answers about where stem cells fit in PCOS management may not be far away.