Premature Ovarian Insufficiency (POI): Causes, Diagnosis and Fertility Options

Premature ovarian insufficiency

POI means the ovaries stop working normally before age 40. It is more common than previously thought — recent data indicate a prevalence of around 3.5%, higher than the roughly 1% quoted in older sources.

It is not the same as early menopause. Ovarian function in POI can fluctuate, and pregnancy occurs in a small proportion of women, so it should not be described as an absolute end to fertility.

Diagnosis is faster than it used to be

Only one elevated FSH above 25 IU is required for diagnosis, alongside irregular or absent periods.

This changed in the 2025 guideline. Previously two raised measurements were required. If you have been told you must wait several weeks for a repeat before anything can happen, that reflects superseded guidance — and the change was made specifically to enable rapid diagnosis and prompt treatment.

Where results are inconclusive, a repeat FSH and/or AMH may be needed. AMH may help confirm the diagnosis where FSH is unclear, but it should not be used as the primary diagnostic test, and it is not recommended for predicting POI.

Why speed matters

POI without hormone therapy is associated with reduced life expectancy, largely through cardiovascular disease. That is a strong recommendation in the guideline, and it is the reason delayed diagnosis is not a neutral inconvenience.

Testing to find a cause

Chromosomal analysis — recommended for all women with non-iatrogenic POI. Strong recommendation.

FMR1 premutation (fragile X) testing — recommended for all women with non-iatrogenic POI. Strong recommendation.

One practical detail that matters: FMR1 testing must be requested as a specific test. Multigene panels and next-generation sequencing do not detect the FMR1 premutation. If you have had "genetic testing" and fragile X was not specifically requested, it has probably not been done.

21-hydroxylase autoantibodies — screening recommended in POI of unknown cause. Strong. A positive result means referral to an endocrinologist for adrenal function testing, because autoimmune POI carries a risk of adrenal insufficiency. If negative, no re-testing is needed later unless symptoms develop.

TSH — measured at diagnosis, repeated every five years or if symptoms arise. Strong.

Two tests not recommended: anti-ovarian antibodies should not be used to diagnose autoimmune POI (strong), and thyroid peroxidase antibody screening is not routinely recommended, because positive TPO antibodies are common in the general population.

Your age should not be used to restrict access to genetic testing.

An exact cause may not be found

The guideline asks clinicians to tell women plainly about the limitations of current knowledge and testing, and that a cause may never be identified. That is a normal outcome, not a failure of investigation.

Hormone therapy

Hormone therapy is recommended until the usual age of menopause, for primary prevention — to reduce morbidity and mortality — whether or not you have oestrogen deficiency symptoms. Strong recommendation.

This is the point most often misunderstood. HT in POI is not symptom relief you can decline if you feel well. It replaces hormones your body would otherwise be producing, and the reason for taking it is bone and cardiovascular protection over decades.

If HT has been framed to you as optional because you have no hot flushes, that is worth revisiting.

Your relatives

Female relatives — sisters, daughters — are at increased risk of POI themselves. Strong recommendation that they be counselled about this.

They should be told the signs and symptoms and advised to seek medical advice promptly if these occur, and that there are no established methods for predicting or preventing POI. Some may wish to consider family planning or fertility preservation.

Where an FMR1 premutation or other genetic cause is found, relatives should be offered genetic counselling and testing.

Fertility

Donor eggs offer good success rates, since outcomes track the donor's age.

For your own eggs, response to stimulation is typically poor. ESHRE (2026) recommends against gonadotropin doses above 300 IU in predicted low responders, and against DHEA, growth hormone and testosterone as adjuvants.

Support

The guideline recommends that the diagnosis is conveyed compassionately, with personalised information and time for questions, and that women are referred to appropriate support groups and mental health care. Women with lived experience of POI informed these recommendations.

If your diagnosis was delivered briefly and without follow-up, that falls short of what the guideline describes.