This article was originally published on March 27, 2019, and updated on September 24, 2024.
All women’s periods are different: For women of reproductive age, your menstrual cycle may last anywhere from 24 to 35 days, and your period may take two to seven days, give or take a day or two.
But while your period may be different from your best friend’s, it should be basically the same each month for you. If you find that the timing of your period varies widely, talk to a doctor.
“I tell people, it can be normal to experience two weird periods a year,” says UNC Health OB-GYN Jacqueline Riely, MD, noting that you might experience occasional changes due to stress or travel. “The rest of the year, you should have normal cycles. If you’re having irregular periods or abnormal bleeding, that should be evaluated. ”
One cause of irregular periods is polycystic ovary syndrome, or PCOS, which is the most common hormonal disorder in women of reproductive age, affecting as much as 15 percent of the population.
Dr. Riely explains the symptoms and treatment options.
PCOS Symptoms and Diagnosis
Getting a PCOS diagnosis can be tricky. Signs and symptoms can vary widely and there’s no singular test to diagnose the condition. In past research, women regularly reported having to see multiple providers over months or years to get a diagnosis.
Dr. Riely says that when she’s considering a PCOS diagnosis, she uses what’s called the Rotterdam criteria, which suggest that a person should exhibit two of the following three symptoms:
- Irregular menstrual periods, including absent periods, unpredictable periods or periods that are too frequent.
- Signs of too much androgen, a male hormone, in the body, which include excess hair growth on the face or chest, hair loss on the head, acne, oily skin, patches of thick, dark skin, or thickness in neck circumference.
- More than 12 cysts (fluid-filled sacs) on the ovaries, as seen on an ultrasound.
Though the name polycystic ovary syndrome might indicate that multiple cysts should be enough to diagnose the condition, Dr. Riely says it’s normal for an ovulating woman to have cysts on the ovaries.
“If I were to perform a pelvic ultrasound on 10 women, probably four or five would have ovarian cysts, and only one or two would know,” she says. “If you have ovaries that are working and ovulating, it’s normal to have some cysts.”
It’s not clear what causes PCOS, but because it can run in families, there may be a genetic factor. What is known is that PCOS increases your risk for other health conditions, which is why it’s important to seek help for symptoms.
The Importance of a PCOS Diagnosis
If you have PCOS, you’re at a higher risk for diabetes and cardiovascular conditions. That’s because people with PCOS often have insulin resistance, in which the body doesn’t use glucose properly. Irregular periods can affect your ability to become pregnant. They can also increase your risk for uterine cancer; when you don’t shed your uterine lining each month via a period, the lining continues to thicken, and that growth can turn cancerous.
“It’s important to rule out other conditions that mimic PCOS, and then it’s important to optimize your health for the risk of these other diseases,” Dr. Riely says. “As a gynecologist, I want to protect your uterus, which means making sure your bleeding is regular, and monitor you closely for diabetes and cardiovascular issues.”
Dr. Riely says that about 80 percent of people who have PCOS also meet the criteria for obesity, but that there’s not a causal relationship between the two, meaning that obesity doesn’t cause PCOS or vice versa, and obesity is not used in diagnosing PCOS. Still, many people who lose weight experience PCOS symptom relief.
“Sometimes, even a 5-to-10-pound weight loss with diet and exercise makes a huge difference in regulating the menstrual cycle,” Dr. Riely says. “For some, weight loss might be all that’s needed.”
While Dr. Riely may refer a person with obesity and PCOS to a dietitian or medical weight loss clinic so that they can get education and support for healthy weight loss, she notes that patients shouldn’t be told they have to reach a certain BMI to begin other treatment.
Treating PCOS and Managing Fertility
PCOS treatment depends on your individual symptoms and fertility goals.
“It will be tailored to your needs and depends on your biggest concern at the moment—do you want to become pregnant, or do you not want to be pregnant?” Dr. Riely says. “Either way, all people with PCOS need treatment to keep them healthy.”
If you don’t desire pregnancy, combined hormonal birth control pills (with both estrogen and progestin) can regulate your menstrual cycle, protecting the lining of your uterus, while also helping with symptoms caused by excess androgen, such as acne or excess hair growth. Progestin-only options, such as a hormonal IUD, can help with irregular periods but may not help with the acne and excess hair growth.
For people with insulin resistance or diabetes, metformin, a drug used for diabetes, can regulate cycles and reduce symptoms.
Some people only find out they have PCOS when they struggle to become pregnant.
“PCOS is a common cause of infertility, but not everyone with PCOS will have infertility,” Dr. Riely says. “If you want to become pregnant, we can provide treatment with a medication that will help you ovulate. In my experience, a general OB-GYN can usually help a person with PCOS conceive, but we can also refer you to a fertility specialist if needed.”
Dr. Riely acknowledges that a PCOS diagnosis and its accompanying health risks can be overwhelming.
“Sometimes our bodies do unpredictable things, but this is manageable with support and resources,” she says. “It’s not a bad thing and there shouldn’t be any stigma associated with this diagnosis. We can help the body do what it’s supposed to do.”
If you’re experiencing irregular menstrual cycles or another concerning symptom, talk to your doctor. Need a doctor? Find one near you.