How PCOS Is Diagnosed

Each woman’s experience of polycystic ovary syndrome (PCOS) is unique because no two women have the exact same symptoms. The current diagnostic criteria for PCOS involves meeting at least two of the following three conditions:

1. Irregular or absent periods
2. Biological or physical signs of hyperandrogenism (high androgen level) without another medical cause
3. A string of small follicles (cysts) on an ultrasound examination

These guidelines, referred to as the Rotterdam Criteria, are the ones most commonly used by endocrinologists in the United States and abroad.

The doctor will want to do a complete physical and pelvic exam and look for physical signs of high androgens and things like testosterone-induced hair growth (specifically on the face, lower abdomen, back, and chest). Other signs may include acne, skin tags, male pattern baldness, and acanthosis nigricans (darkened thick skin on the neck, thighs, armpits or vulva).

When a woman has infrequent, absent, or irregular periods (eight or fewer cycles per year), it is a sign that ovulation may not be occurring and could indicate PCOS.

To better confirm PCOs as the cause, the doctor will rule out other conditions in which irregular menstruation common, such as thyroid disease, hyperprolactinemia, Cushing's syndrome, and congenital adrenal hyperplasia.

The doctor will ask you about any unusual symptoms you may have noticed, so make sure to mention any of your concerns.

Writing a list before you go may help you remember important points to ask about. This may include specific facts and figures about the frequency of periods, when they occurred, what happened when you had them, and what other symptoms you had between periods. This can help your doctor determine if you are ovulating.

A transvaginal ultrasound may or not be performed to rule out PCOS. In a transvaginal ultrasound probe is placed inside the vagina, which allows the physician to examine the reproductive organs and look for abnormalities. The thickness of the endometrium can be measured.

Often times these follicles are called "cysts". There are many women who have cystic-appearing ovaries without symptoms of hyperandrogenism, and many women who have been diagnosed with PCOS who do not have classically cystic ovaries. Some doctors find the use of transvaginal ultrasound in adolescents unnecessary. 

Blood work will most likely be taken. Besides hormonal testing, like for testosterone, other sex hormones should be checked such as follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin. Your doctor may test for other associated conditions like high cholesterol and insulin resistance.

A newer blood test, which evaluates the anti-Mullerian hormone (AMH) in women, is now being used by some physicians as a diagnostic tool as well.

An endometrial biopsy can be performed to determine if your endometrial tissue is in the correct phase or to test for endometrial cancer. This risk of endometrial cancer increases with the number of and length of time between missed periods.

The biopsy can be done in your doctor’s office and is relatively painless, although you may experience minimal cramping during the procedure. A small amount of tissue is removed from your uterus through a thin catheter placed into through the cervix and into the uterus. This tissue is then analyzed in the context of your cycle and examined for cancer cells.

A Word From Verywell

While this may all seem overwhelming, remember that you are not alone. As the most common endocrine disorder among women of childbearing age, there are many women with PCOS who have been through this. Reach out to a support group and the people who care about you. Following your doctor's advice and learning about your disease is the best way to manage it.