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Frequently Asked Questions about PCOS

Polycystic Ovary Syndrome (PCOS Twin Study)

Two young women smiling

What is PCOS?

PCOS occurs because of certain hormone imbalances. With PCOS, a woman's body secretes abnormally high levels of male hormones (androgens) and this counteracts her ovaries' ability to make enough of the female hormone (progesterone) needed for normal menstruation. Because of the low level of female hormones, women with PCOS typically have fewer periods than most women (called oligomenorrhea) and sometimes have no periods at all (called amenorrhea). Their periods can also be irregular with lengthy bleeding episodes, light or heavy flows, or frequent spotting.

Most but not all women with PCOS get small, pea-size cysts on their ovaries. The cysts are caused by follicles (fluid-filled sacs that contain an egg) that have matured in the ovary, but because of the abnormal hormone levels, were never released. In PCOS, one or both of the ovaries can also become enlarged, sometimes up to 1.5-3 times their normal size

What causes PCOS?

No one knows exactly what causes PCOS, which is why we are conducting this study. Genetics are thought to be a factor, but the environment may also play a part. Many women with PCOS have a weight problem, so researchers are looking at the connection between weight and PCOS.

What are the symptoms of PCOS?

There are numerous symptoms of PCOS. Some women may only have one or two and others may have them all. The symptoms include, but are not limited to:

  • Infrequent periods, no periods, and/or irregular bleeding
  • Inability to get pregnant
  • Acne
  • Excess hair growth on the face, chest, stomach, back, arms and legs
  • Male pattern baldness
  • Weight gain
  • Diabetes, and
  • Velvety, light brown-to-black markings on the skin around the neck and under the arms.

What happens when you have PCOS?

PCOS is associated with reproductive problems, such as infertility, miscarriages and preeclampsia. It may also be associated with gestational diabetes, Type-2 (adult-onset) diabetes and obesity. It may also cause cardiovascular problems, such as high cholesterol, high blood pressure and coronary artery disease. Finally, a woman with PCOS may have acne and abnormal hair growth.

How is PCOS diagnosed?

PCOS is diagnosed based on a history of irregular menstrual cycles and symptoms of excess androgens such as increased hair growth, acne or male-pattern scalp hair loss. Pelvic ultrasound can also be used to confirm the diagnosis of PCOS in a woman with irregular menstrual cycles and/or symptoms of excess androgens. Additional blood tests (cholesterol, triglycerides, and glucose) are important in evaluating for associated metabolic complications such as abnormal cholesterol or diabetes.

How is PCOS treated?

PCOS can not be cured, but the symptoms can be managed. If a woman does not plan to become pregnant, she can take birth control pills to regulate her periods, reduce male hormone levels in her blood, and clear her acne.

One medication to treat Type-2 diabetes, known as Metformin or Glucophage, affects the way insulin regulates glucose and decreases testosterone production. However, doctors discovered that when some women with PCOS take this drug, ovulation can return to normal and abnormal hair growth can slow down after a few months of use.

For women who have trouble with getting pregnant, fertility drugs can be given to stimulate ovulation.

Maintaining a healthy weight can also help women manage PCOS. Physical activity and a healthy diet will help the body lower glucose levels, use insulin more efficiently, and may restore normal periods.

What are the objectives of this study?

This study is Phase 2 of a multi-phase research study to identify the genetic and environmental factors involved in PCOS. The goal of Phase 2 is to identify a group of female twin pairs in which one or both twins have PCOS. The information collected during the study will be used to establish agreement rates for PCOS in identical and fraternal twins and to establish whether PCOS is an inherited syndrome.

What does this study involve?

One or both twins in a pair will be asked to undergo a blood test to determine the amount of testosterone in your body. The blood will be collected at your convenience by a home health agency nurse and sent to the Mayo Clinic for testing. Based on this result and the results from the earlier Mid-Atlantic Twin Registry (MATR) survey, both twins in a pair may be asked to undergo a medical exam for PCOS at Duke University Medical Center (DUMC) in Durham, NC. The evaluation, however, will be contingent upon whether your twin sister can be contacted about the study, and also agrees to participate by undergoing a similar evaluation.

For the medical evaluation, we hope that you will agree to travel to Durham, North Carolina for a 4-6 hour appointment at Duke University Medical Center. We will pay for all of your travel-related expenses for this visit. Once there, you will have a blood test to check your levels of various hormones, as well as the level of glucose. You will then be asked to drink a sugar drink then have your glucose level checked again via another blood test. Then a female study doctor will perform a physical exam, and a sonographer will perform a transvaginal ultrasound on you. If you can't travel to Duke for the evaluation, we are trying to initiate study centers at other locations in the future.

If your testosterone level is not elevated, you are not eligible to undergo the medical evaluation at this time. However, you might have another form of PCOS (an intermediate form) that doesn't involve having high testosterone levels. We hope to study this form of PCOS in the future, and if we do, we will contact you to ask you to undergo a medical evaluation at that time.

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Last Reviewed: November 04, 2008