Polycystic ovary syndrome (PCOS) is a hormonal imbalance that occurs when your ovaries (the organ that produces and releases eggs) create excess hormones. If you have PCOS, your ovaries produce unusually high levels of hormones called androgens. This causes your reproductive hormones to become imbalanced. As a result, people with PCOS often have irregular menstrual cycles, missed periods and unpredictable ovulation. Small follicle cysts (fluid-filled sacs with immature eggs) may be visible on your ovaries on ultrasound due to lack of ovulation (anovulation). However, despite the name "polycystic," you don’t need to have cysts on your ovaries to have PCOS. The ovarian cysts aren’t dangerous or painful.

PCOS is one of the most common causes of female infertility. It can also increase your risk of other health conditions.

What age does PCOS start?

Females can get PCOS any time after puberty. Most people are diagnosed in their 20s or 30s when they’re trying to get pregnant. You may have a higher chance of getting PCOS if you have obesity or if other people in your biological family have PCOS.

What are the signs of polycystic ovary syndrome (PCOS)?

The most common signs and symptoms of PCOS include:

• Irregular periods: Abnormal menstruation involves missing periods or not having a period at all. It may also involve heavy bleeding during periods.
• Abnormal hair growth: You may grow excess facial hair or experience heavy hair growth on your arms, chest and abdomen (hirsutism). This affects up to 70% of people with PCOS.
• Acne: PCOS can cause acne, especially on your back, chest and face. This acne may continue past your teenage years and may be difficult to treat.
• Obesity: Between 40% and 80% of people with PCOS have obesity and have trouble maintaining a weight that’s healthy for them.
• Darkening of the skin: You may get patches of dark skin, especially in the folds of your neck, armpits, groin (between the legs) and under your breasts. This is known as acanthosis nigricans.
• Cysts: Many people with PCOS have ovaries that appear larger or with many follicles (egg sac cysts) on ultrasound.
• Skin tags: Skin tags are little flaps of extra skin. They’re often found in your armpits or on your neck.
• Thinning hair: People with PCOS may lose patches of hair on their head or start to bald.
• Infertility: PCOS is the most common cause of female infertility. Not ovulating regularly or frequently can result in not being able to conceive.