Semaglutide and PCOS: early findings from the RESTORE fertility trial

PCOS - polycystic ovary syndrome - affects an estimated 8-13% of women of reproductive age and is the most common cause of infertility from failure to ovulate. Its metabolic and reproductive complications are deeply intertwined: insulin resistance drives androgen excess, androgen excess disrupts ovulation, and excess weight amplifies both. The standard treatment options have long forced women into an uncomfortable choice - address the metabolic problem or address the reproductive problem, but rarely both at once. A proof-of-concept analysis from the RESTORE clinical trial, published in Fertility and Sterility on June 9, 2026, suggests injectable semaglutide may be capable of addressing both simultaneously.

TL;DR

Early data from the University of Colorado's RESTORE trial found that women with PCOS or PMOS who achieved at least 10% body weight loss on semaglutide showed faster-than-expected restoration of ovulation. The study is a proof-of-concept analysis - not a definitive trial - and larger studies are needed. The trial is still enrolling participants aged 12-35.

PCOS, PMOS, and the metabolic-reproductive loop

PCOS is being increasingly reconceptualised as PMOS - polyendocrine metabolic ovarian syndrome - to better reflect the metabolic nature of the disorder. The name change captures something important: for most women with this condition, the ovarian dysfunction is downstream of metabolic disruption, not the primary problem.

The cycle works like this. Insulin resistance - present in 65-70% of women with PCOS regardless of weight - causes the pancreas to overproduce insulin. High insulin directly stimulates the ovaries to produce excess androgens, particularly testosterone. Androgen excess disrupts the hormonal signalling required for normal follicle development and ovulation. Weight gain, which is both a cause and consequence of insulin resistance in PCOS, amplifies all three pathways simultaneously.

Existing treatments address individual parts of this loop. Metformin reduces insulin resistance but modestly. Hormonal contraceptives suppress androgens but prevent pregnancy. Lifestyle interventions can address all three pathways but are difficult to sustain at the caloric deficit required for meaningful change. The frustrating gap, as Dr Melanie Cree of the University of Colorado put it, is that "women with PMOS frequently face a frustrating choice between treatments that target reproductive symptoms and those that address metabolic health."

What the RESTORE trial found

The RESTORE clinical trial, led by Dr Cree and based at the University of Colorado Anschutz Medical Campus, is testing injectable semaglutide in participants aged 12-35 with PCOS or PMOS and obesity. The trial is ongoing and still enrolling; the June 9, 2026 publication in Fertility and Sterility presents a proof-of-concept analysis from early participants.

The key finding: participants who achieved at least 10% body weight loss on semaglutide showed improvements in ovulation and reproductive function that appeared earlier than the research team expected based on prior weight loss data. The medication was "incredibly promising when someone responds with 10% weight loss," according to Dr Cree.

The study addresses a significant clinical gap: as Dr Cree noted, "although GLP-1 medications have transformed obesity treatment, there remains a significant need for rigorous data examining how these therapies affect fertility." The existing GLP-1 trial data was collected in populations where pregnancy was actively excluded - meaning women of reproductive age who might actually benefit from fertility improvements have been systematically absent from the trial evidence base.

The 10% weight loss threshold

The 10% body weight loss threshold is not arbitrary. It corresponds to a well-established inflection point in PCOS research. Earlier studies consistently showed that 5-10% weight loss produced modest but inconsistent hormonal improvements, while sustained loss of 10% or more was associated with reliable reductions in testosterone levels, improvements in menstrual regularity, and restoration of ovulation in a significant proportion of women.

What the RESTORE data suggests is that semaglutide-mediated weight loss - when it reaches that 10% threshold - may trigger reproductive improvements faster than comparable weight loss achieved through diet alone. This could reflect GLP-1-specific effects on insulin signalling, on androgen production pathways, or on hypothalamic-pituitary signalling that governs ovulation - all of which are active areas of research.

GLP-1 medications and PCOS: the broader evidence picture

The RESTORE findings sit within a growing body of earlier research. A meta-analysis published in PMC (PMC12297736) examining semaglutide plus metformin in PCOS reported a 60% pregnancy rate in the combination group, substantially higher than metformin alone. Separate observational studies have documented improved menstrual regularity, reduced androgen levels, and higher ovulation rates in GLP-1 users with PCOS compared to matched controls.

The mechanism behind fertility improvement is most likely multi-pathway:

• Reduced insulin resistance → lower ovarian androgen production → improved follicle development
• Lower testosterone levels → more regular ovulatory cycles
• Weight loss → reduced leptin excess → normalised hypothalamic-pituitary-ovarian signalling
• Improved metabolic function → better endometrial receptivity for embryo implantation

Whether GLP-1 receptor agonism contributes directly beyond these metabolic effects - through GLP-1 receptors in the ovary or uterus - is not yet established in human studies.

Important limitations and what the research cannot yet tell us

The RESTORE findings are proof-of-concept, not definitive evidence. Several important questions remain open:

• The trial is still enrolling - full results from the complete RESTORE dataset have not yet been published
• Larger, longer-term randomised trials are needed to confirm durability of reproductive benefits
• The optimal duration of semaglutide treatment before conception has not been established
• What happens to hormonal and metabolic status after stopping semaglutide - and whether fertility benefits persist - is not yet known
• The trial includes participants as young as 12, and the safety and long-term effects of GLP-1 medications in adolescents with PCOS remain under investigation

Semaglutide is not approved for use during pregnancy. Women using GLP-1 medications who are attempting to conceive need careful medical guidance about when to stop the medication and what contraception, if any, to use during treatment.

Practical considerations for women with PCOS on GLP-1 medications

If you have PCOS or PMOS and are currently on a GLP-1 medication, or are considering one, these are the most important points based on current evidence:

• Discuss your fertility goals explicitly with both your GLP-1 prescriber and your gynaecologist or reproductive endocrinologist - the intersection of these two treatment areas requires coordinated care
• GLP-1 medications improve insulin sensitivity and can restore ovulation even if you have been irregular for years - this means unintended pregnancy is possible, including in women who previously believed they were infertile
• If you are actively trying to conceive, the current evidence suggests that sustained 10%+ weight loss on semaglutide is associated with meaningful reproductive improvements - but semaglutide must be stopped before conception
• Metformin continues to have an evidence base for PCOS management, and some evidence suggests combination with semaglutide may produce higher pregnancy rates than either alone

Nutrition for reproductive health on GLP-1 medications

The nutrients that support reproductive health - folate, iron, vitamin B12, zinc, and vitamin D - are the same nutrients most commonly depleted when food intake drops substantially on GLP-1 therapy. Folate deficiency is associated with impaired ovulation and, critically, neural tube defects if pregnancy occurs. Iron deficiency is common in women with PCOS due to heavy or irregular menstrual bleeding. Vitamin B12 and zinc both support the hormonal signalling systems that regulate reproductive function.

Women with PCOS on GLP-1 medications are at particular risk for these deficiencies because they often start with lower nutritional status due to irregular eating patterns associated with the condition, and then compound this with the reduced intake that GLP-1 therapy produces. GLP-1 Shield is formulated to address these specific gaps, providing targeted support for the nutritional foundations that reproductive health depends on.

Frequently asked questions

Can semaglutide help with PCOS fertility?

Early findings from the RESTORE trial suggest that women with PCOS who achieve at least 10% weight loss on semaglutide show faster-than-expected improvements in ovulation and reproductive function. This is promising proof-of-concept data, but the trial is ongoing and larger studies are needed before definitive conclusions can be drawn. GLP-1 medications are not currently approved or prescribed specifically for PCOS fertility treatment.

Can I get pregnant while taking Ozempic or Wegovy?

Yes - GLP-1 medications can restore ovulation in women with PCOS who were previously irregular, making unintended pregnancy possible even in women who believed they were infertile. Semaglutide is not approved for use during pregnancy and should be stopped before conception. Discuss contraception and pregnancy planning explicitly with your prescriber if you are of reproductive age and sexually active.

How much weight loss is needed to improve PCOS symptoms?

Research consistently shows that sustained weight loss of 10% or more of body weight produces reliable improvements in testosterone levels, menstrual regularity, and ovulation rates in women with PCOS. The RESTORE trial's early findings suggest semaglutide-mediated weight loss may trigger reproductive improvements at this threshold faster than diet-induced weight loss alone.

What nutrients do women with PCOS need on GLP-1 medications?

The most important nutrients for reproductive health are folate, iron, vitamin B12, zinc, and vitamin D - all of which can be depleted when food intake drops substantially on GLP-1 therapy. Women with PCOS are at particular risk because irregular eating patterns and heavy menstrual bleeding may have created pre-existing deficiencies before starting a GLP-1 medication. Blood testing before and during treatment is advisable.