What is PCOS?
Polycystic ovary syndrome (PCOS) is a common condition. If you experience symptoms of polycystic ovary syndrome (PCOS), they'll usually become apparent in your late teens or early 20s. Not everyone with PCOS will have all of the symptoms, and each symptom can vary from mild to severe.

Common symptoms of PCOS include:
irregular periods or no periods at all
difficulty getting pregnant (because of irregular ovulation or failure to ovulate)
excessive hair growth (hirsutism) – usually on the face, chest, back or buttocks
weight gain
thinning hair and hair loss from the head
oily skin or acne
The exact cause of PCOS is not known. Most experts think that several factors, including genetics, play a role. A high level of androgens is another. Androgens are sometimes called "male hormones," although everyone has androgens.
Polycystic ovaries. Your ovaries become enlarged and contain many fluid-filled sacs (follicles) that surround the eggs. But despite the name, you do not actually have cysts if you have PCOS.
PCOS can lead to fertility problems
PCOS is one of the most common causes of infertility. Many discover they have PCOS when they're trying to get pregnant and are unsuccessful. As you already know, during each menstrual cycle, the ovaries release an egg into the uterus. A person with PCOS often fails to ovulate or ovulate infrequently, which means they have irregular or absent periods and find it difficult to get pregnant.