PMOS (PCOS): New Name, Symptoms and Treatment

What is PMOS (polycystic ovary syndrome)?

Long known as polycystic ovary syndrome (PCOS), this is the most common hormonal disorder in women of reproductive age, affecting about one in eight women. In May 2026 a global consensus report published in The Lancet set its new name: Polyendocrine Metabolic Ovarian Syndrome (PMOS).

In PMOS the hormonal balance between the brain, ovaries, pancreas (insulin) and fat tissue is disturbed. Ovulation becomes irregular, male hormones (androgens) rise relatively, and the body may respond less well to insulin. Genetic predisposition plays an important role. Weight gain can worsen symptoms, but PMOS also occurs in women of normal weight.

Why was PCOS renamed PMOS?

The new name is the result of a multistep consensus process involving 56 academic, clinical and patient organisations and surveys and workshops with patients and health professionals from every world region. The main reasons are:

"Cyst" is misleading: the structures seen on ultrasound are not true cysts but small follicles (egg sacs) whose development has stalled. There is no increase in abnormal ovarian cysts, and some women with the diagnosis do not have this ultrasound appearance at all.
It is not limited to the ovary: the old name obscured metabolic features such as insulin resistance, diabetes and cardiovascular risk factors, contributing to delayed diagnosis and fragmented care.
It is a multisystem condition: "polyendocrine" refers to several hormone systems, "metabolic" to insulin and fat metabolism, and "ovarian" to ovulation and reproduction. Skin (acne, excess hair, hair loss) and mental health (anxiety, depression, body image) are also involved.

A transition period with education and alignment of health systems is planned. During this time you will see both PCOS and PMOS in reports and resources; they describe the same condition. The name change does not change the condition itself: diagnosis and treatment continue to follow the 2023 International Evidence-based PCOS Guideline.

Symptoms

Symptoms vary widely and not every woman has all of them.

Irregular periods: cycles longer than 35 days, fewer than 8 periods a year, or no periods
Signs of excess androgens: excess facial, chest and abdominal hair (hirsutism), acne, oily skin and scalp hair thinning
Metabolic signs: tendency to gain weight, difficulty losing weight, dark skin patches on the neck and armpits (acanthosis nigricans)
Fertility: difficulty conceiving because of irregular ovulation
Mental health and quality of life: anxiety, low mood, body-image concerns and a tendency to eating disorders
Sleep: snoring and sleep apnoea, particularly with excess weight

How is PMOS (PCOS) diagnosed?

In adults, diagnosis follows the Rotterdam criteria as updated by the international guideline. At least two of the following three are required:

Ovulatory dysfunction: irregular, infrequent or absent periods
Excess androgens: clinical signs such as excess hair and acne, or a high blood testosterone level
Polycystic ovarian morphology or high AMH: 20 or more small follicles in one ovary or an ovarian volume of 10 mL or more on transvaginal ultrasound. Under the 2023 guideline, a high blood AMH (anti-Müllerian hormone) can be used instead of ultrasound in adults.

If a woman has both irregular cycles and excess androgens, ultrasound or AMH is not needed. In adolescents both irregular cycles and excess androgens are required; ultrasound and AMH are not recommended within 8 years of the first period, because many follicles can be normal at this age.

Conditions that can mimic PMOS must be excluded, with tests such as thyroid hormones, prolactin and 17-hydroxyprogesterone for adrenal causes. Rapidly progressive virilisation calls for investigation of androgen-secreting tumours.

Long-term metabolic and general health risks

Insulin resistance, which can occur even at normal weight, raises several long-term risks:

Impaired glucose tolerance, type 2 diabetes and gestational diabetes
High cholesterol and triglycerides, high blood pressure
More cardiovascular risk factors
Thickening of the uterine lining (endometrial hyperplasia) and a higher risk of endometrial cancer when periods are absent for long periods
Obstructive sleep apnoea and fatty liver
Depression and anxiety

Guidelines therefore recommend assessing glycaemic status at diagnosis and every 1-3 years depending on risk (preferably with an oral glucose tolerance test), checking lipids, measuring blood pressure yearly and monitoring weight. Mood and eating behaviour should also be asked about.

Prof. Dr. İkbal Kaygusuz is a co-author of numerous international publications on cardiovascular risk markers in PCOS (pentraxin 3, hepcidin, ADMA), the effect of treatment on these markers and the links between PCOS and other systems.

Lifestyle: the foundation of care

Healthy eating and regular physical activity are recommended for all women with PMOS, regardless of weight. In women with excess weight, losing even 5-10% of body weight can clearly improve cycles, ovulation and metabolic values.

No specific diet has been shown to be superior; a sustainable, balanced and individual eating pattern is key.
At least 150 minutes of moderate or 75 minutes of vigorous activity a week, plus muscle-strengthening on two days, is recommended.
Less sitting, good sleep and stress management also help.

Treatment

Treatment is tailored to symptoms, age, metabolic status and fertility wishes.

Cycle control and protecting the uterine lining

For women not seeking pregnancy, the combined pill regulates cycles, protects the uterine lining and reduces androgen-related symptoms. When the pill is unsuitable, periodic progestogen or a hormonal intrauterine device can protect the lining.

Excess hair, acne and hair loss

At least 6 months is usually needed to judge the pill's effect on hair growth. Laser and other hair-removal methods support treatment. If the response is insufficient, anti-androgens can be added together with effective contraception; they must not be used in pregnancy. Dermatology input is sought when needed.

Metabolic treatment

Metformin may be added for marked insulin resistance, weight management or impaired glucose tolerance. In suitable adults, anti-obesity medications may be considered; they must be stopped before trying to conceive. Evidence for supplements such as inositol is limited.

Mental health support

Appropriate psychological support is part of care for women with anxiety, depression or eating disorder symptoms.

PMOS and conception: ovulation induction

The main reason for difficulty conceiving is irregular ovulation. Before treatment the couple is assessed together: the partner's semen analysis, tubal patency when needed, and optimisation of weight, blood sugar and blood pressure.

Letrozole: the first-line medication for inducing ovulation. Clomiphene citrate, alone or with metformin, is an alternative.
Gonadotropin injections: second-line for women who do not respond to tablets, started at a low dose with close ultrasound monitoring to reduce the risk of multiple pregnancy.
Laparoscopic ovarian drilling: a second-line option in selected women, especially when laparoscopy is needed for another reason.
Insemination and IVF: planned when ovulation treatment has not led to pregnancy or another fertility factor is present.

PMOS and IVF

Because the ovaries contain many follicles, they may respond strongly to medication, raising the risk of ovarian hyperstimulation syndrome (OHSS). An antagonist protocol, careful dosing, a GnRH agonist trigger when appropriate and freezing embryos for transfer in a later cycle reduce this risk. Metformin may also help in some protocols.

PMOS and pregnancy

Gestational diabetes, gestational hypertension, pre-eclampsia and preterm birth are more common. Optimising weight and blood sugar before pregnancy, taking folic acid and earlier glucose screening in pregnancy are recommended.

When should you see a doctor?

Your cycles are longer than 35 days, you have fewer than 8 periods a year, or no period for more than three months
You notice excess hair growth, persistent acne or hair thinning
You have unexplained weight gain or raised blood sugar
You have very heavy or prolonged bleeding after long gaps
You have not conceived after one year (six months if 35 or over) of regular intercourse; women with very irregular cycles should be assessed sooner

Frequently Asked Questions

Are PCOS and PMOS the same condition?

Yes. PMOS (Polyendocrine Metabolic Ovarian Syndrome) is the new name, set in 2026, for polycystic ovary syndrome (PCOS). The condition, diagnostic criteria and treatments are the same; the new name reflects its hormonal, metabolic and reproductive features more accurately. Both names are used during the transition period.

Can I have PMOS without ovarian cysts?

Yes. The structures on ultrasound are small follicles, not true cysts, and this appearance is not required for diagnosis. Irregular cycles plus excess androgens are enough.

Can women with PMOS get pregnant?

Yes. Most conceive with ovulation treatment such as letrozole; gonadotropins, insemination and IVF are further options. Optimising weight and blood sugar beforehand is recommended.

Can slim women have PMOS?

Yes. PMOS occurs in women of normal weight and slim women, and insulin resistance can be present regardless of weight, so metabolic checks are recommended for all.

Does PMOS go away?

It is a lifelong tendency, but symptoms can be largely controlled with lifestyle changes and treatment. Regular health checks remain important after menopause because of metabolic risks.

Sources

The information on this website is for general information only and does not replace a medical consultation.

Infertility and IVF4 min read

PMOS (Polycystic Ovary Syndrome – PCOS): The New Name, Symptoms and Treatment