Stem Cell Therapy for Female Infertility

What This Article Covers

"Female infertility" covers many distinct problems, but stem cell research has concentrated on two very different fronts: repairing a damaged uterine lining (as in Asherman's syndrome and thin endometrium) and trying to restore egg-producing function in ovaries affected by diminished ovarian reserve. This article explains what stem cells are being tested for, what the actual published evidence shows for each use, and why one of these applications is producing genuinely encouraging early data while the other is being sold commercially well ahead of the science.

Overview

No stem cell therapy is FDA-approved for treating female infertility of any kind. That said, research groups — most notably a team led by Amparo Santamaria and colleagues in Valencia, Spain — have run real clinical trials using a patient's own bone marrow stem cells to regenerate scarred or thin endometrial tissue, with results published in peer-reviewed journals including Human Reproduction and, most recently, Nature Communications. A separate and much less settled line of work explores whether stem cell injections into the ovaries can "activate" dormant follicles in women with diminished ovarian reserve — an approach frequently marketed by fertility clinics as "ovarian rejuvenation," despite far thinner evidence.

How It's Thought to Work

For uterine applications, doctors mobilize a patient's own bone marrow-derived stem cells (specifically CD133-positive cells, a marker found on early progenitor cells) using a growth factor injection, collect them from the blood, and deliver them directly into the uterine cavity via catheter. The theory is that these cells secrete growth factors and signaling molecules that promote new blood vessel formation and tissue regeneration in endometrium that has been scarred by adhesions or is too thin to support embryo implantation. For ovarian applications, the proposed mechanism is different and far more speculative: proponents suggest that stem cell-enriched injections into ovarian tissue might "wake up" follicles that are dormant but not yet depleted. There is no credible evidence that stem cells create new eggs in humans, and this distinction matters — it separates a biologically plausible repair mechanism from a claim that remains unproven.

What the Evidence Shows

The endometrial research is the more mature story. A 2016 pilot cohort study by Santamaria and colleagues in Human Reproduction first showed that CD133+ bone marrow stem cell infusions could increase endometrial thickness in women with severe, treatment-resistant Asherman's syndrome. That early work has now been followed by a formal Phase 1/2 trial, published in Nature Communications (2025), in which 20 women with moderate-to-severe, treatment-refractory Asherman's syndrome received the therapy. The results are notable: mean endometrial thickness rose from 3.80 mm to 5.29 mm, intrauterine adhesion scores dropped significantly, and 11 of the 20 women (55%) went on to become pregnant, with 6 (30%) delivering healthy babies — in a population that had already failed standard hysteroscopic surgery. No serious treatment-related adverse events were reported. It's a small, single-arm trial without a control group, so it isn't proof the therapy works better than watchful waiting or repeat surgery — but for women who had run out of standard options, this is a real, published signal worth taking seriously.

The ovarian side of the picture is murkier. A 2025 study in the journal Aging (the "Stem Cell Regenera" study, also from the Santamaria/IVI Clinics group) followed 145 women aged 26–44 with poor ovarian response who underwent stem cell mobilization and intraovarian injection of stem-cell-factor-enriched platelet-rich plasma. About 70% showed signs of "oocyte activation" (follicle growth or hormonal changes), roughly 7% conceived spontaneously, and 14% conceived via IVF afterward. But this was a retrospective, uncontrolled, real-world case series — not a randomized trial — and the authors themselves call for larger controlled studies before conclusions can be drawn. The FDA has separately warned consumers about clinics marketing unapproved stem cell products, and reproductive medicine commentators have flagged the added concern that ovarian tissue is cancer-prone, making unregulated intraovarian injections a genuine safety question, not just an efficacy one.

Who Might Be a Candidate

• Women with moderate-to-severe Asherman's syndrome (intrauterine adhesions) that has not resolved with standard hysteroscopic adhesiolysis
• Women with persistently thin endometrium that has not responded to hormonal therapy and is preventing embryo transfer
• Patients being evaluated within a formal clinical trial for endometrial stem cell therapy, ideally at an academic reproductive medicine center
• Women considering ovarian "rejuvenation" injections should treat this as experimental and unproven, not a validated fertility treatment
• Not a fit: anyone seeking a guaranteed pregnancy outcome, or being offered ovarian stem cell injections outside a registered clinical trial with informed consent about the experimental nature of the treatment

Bottom Line

Stem cell therapy for Asherman's syndrome and thin endometrium is a legitimate, actively researched area with a small but real published trial showing meaningful pregnancy and live birth rates in women who had exhausted other options — encouraging, though still early and unconfirmed by larger controlled studies. Stem cell "ovarian rejuvenation," by contrast, remains commercially marketed well ahead of the evidence: the underlying mechanism is unproven in humans, the best available data comes from an uncontrolled case series, and no version of this therapy is FDA-approved. Patients considering either option should seek care through registered clinical trials rather than clinics selling these treatments as established fertility solutions.