Ovarian Cancer Prevention (PDQ®)
What is prevention?
Cancerprevention is action taken to lower the chance of getting
cancer. By preventing cancer, the number of new cases of cancer
in a group or population is lowered. Hopefully, this will lower
the number of deaths caused by cancer.
To prevent new cancers from starting, scientists look at risk
factors and protective factors. Anything that increases your
chance of developing cancer is called a cancer risk factor;
anything that decreases your chance of developing cancer is
called a cancer protective factor.
Some risk factors for cancer can be avoided, but many cannot.
For example, both smoking and inheriting certain genes are
risk factors for some types of cancer, but only smoking can be
avoided. Regular exercise and a healthy diet may be protective
factors for some types of cancer. Avoiding risk factors and
increasing protective factors may lower your risk but it does
not mean that you will not get cancer.
Different ways to prevent cancer are being studied, including:
- Changing lifestyle or eating habits.
- Avoiding things known to cause cancer.
- Taking medicines to treat a precancerouscondition or to
keep cancer from starting.
General Information About Ovarian Cancer
Ovarian cancer is a disease in which malignant (cancer) cells
form in the ovaries.
The ovaries are a pair
of organs in the female reproductive
system. They are in the pelvis, one on each side of the
uterus (the hollow, pear-shaped
organ where a fetus grows). Each
ovary is about the size and shape of an almond. The ovaries make eggs and
female hormones (chemicals that
control the way certain cells or
organs work in the body).Anatomy of the female reproductive system. The organs in the female reproductive system include the uterus, ovaries, fallopian tubes, cervix, and vagina. The uterus has a muscular outer layer called the myometrium and an inner lining called the endometrium.
Ovarian cancer is the leading cause of death from cancer of the
female reproductive system.
Since 1992, the number of new cases of ovarian cancer has stayed about the same. The number of deaths from ovarian cancer has slightly decreased since 2002.
It is hard to find ovarian cancer early. Early ovarian cancer may not cause any symptoms. When symptoms do appear, ovarian cancer is often advanced.
See the following PDQ summaries for more information about ovarian cancer:
Ovarian Cancer Prevention
Avoiding risk factors and increasing protective factors may
help prevent cancer.
Avoiding cancerrisk factors may help prevent certain cancers. Risk factors include smoking, being overweight, and not getting enough exercise. Increasing protective factors such as quitting smoking, eating a healthy diet, and exercising may also help prevent some cancers. Talk to your doctor or other health care professional about how you might lower your risk of cancer.
The following risk factors may increase
the risk of ovarian cancer:
Family history of ovarian cancer
A woman whose mother or sister had ovarian cancer has an increased risk of ovarian cancer. A woman with two or more relatives with ovarian cancer also has an increased risk of ovarian cancer.
The risk of ovarian cancer is increased in women who have inherited certain changes in the following genes:
Hormone replacement therapy
The use of estrogen-only hormone replacement therapy (HRT) after menopause increases the risk of
ovarian cancer. The longer estrogen replacement therapy is used, the greater the risk may be. It is not clear whether the risk of ovarian cancer is increased with the use of HRT that has both estrogen and progestin.
The use of fertilitydrugs may be linked to an increased
risk of ovarian cancer.
The use of talc may increase the risk of ovarian cancer. Talcum powder dusted on the perineum (the area between the vagina and the anus) may reach the ovaries by entering the vagina.
Having too much body fat, especially during the teenage years, is linked to an increased risk of ovarian cancer. Being obese is linked to an increased risk of death from ovarian cancer.
Being taller than 5 feet 8 inches is linked to an increased risk of ovarian cancer.
The following protective factors may
decrease the risk of ovarian cancer:
The use of oral contraceptives (“the pill”) lowers ovarian
cancer risk. The longer oral contraceptives are used, the lower the risk may
be. The decrease in risk may last up to 25 years after a woman has stopped using oral
Taking oral contraceptives increases the risk of blood clots. This risk is higher in women who also smoke. There may be a slight increase in a woman’s risk of breast cancer during the time she is taking oral contraceptives. This risk decreases over time.
Pregnancy and breastfeeding
Pregnancy and breastfeeding are linked to a decreased risk of ovarian cancer. Ovulation stops or occurs less often in women who are pregnant or breastfeeding. Some experts believe that women who ovulate less often have a decreased risk of ovarian cancer.
Bilateral tubal ligation or hysterectomy
The risk of ovarian cancer is decreased in women who have a bilateraltubal ligation (surgery to close both fallopian tubes) or a hysterectomy (surgery to remove the uterus).
Some women who have a high risk of ovarian cancer may choose to have a prophylactic oophorectomy (surgery to remove both ovaries when there are no signs of cancer). This includes women who have inherited certain changes in the BRCA1 and BRCA2 genes or in the genes linked to hereditary nonpolyposis colon cancer (HNPCC). (See the PDQ summary on Genetics of Breast and Ovarian Cancer for more information.)
It is very important to have a cancer risk
assessment and counseling before making this decision. These and other factors should be discussed:
- Early menopause: The drop in estrogen levels caused by removing the ovaries can cause early menopause. Symptoms of menopause include the following:
These symptoms may not be the same in all women. Hormone replacement therapy (HRT) may be needed to lessen these symptoms.
- Hot flashes.
- Night sweats.
- Trouble sleeping.
- Mood changes.
- Decreased sex drive.
- Heart disease.
- Vaginal dryness.
- Osteoporosis (decreased bone density).
- Risk of ovarian cancer in the peritoneum: Women who have had a prophylacticoophorectomy continue to have a small risk of ovarian cancer in the peritoneum (thin layer of tissue that lines the inside of the abdomen). This may occur if ovarian cancer cells had already spread to the peritoneum before the surgery or if some ovarian tissue remains after surgery.
Cancer prevention clinical trials are used to study ways
to prevent cancer.
Cancer preventionclinical trials are used to study ways to
lower the risk of developing certain types of cancer. Some
cancer prevention trials are conducted with healthy people who
have not had cancer but who have an increased risk for cancer.
Other prevention trials are conducted with people who have had
cancer and are trying to prevent another cancer of the same type
or to lower their chance of developing a new type of cancer.
Other trials are done with healthy volunteers who are not known
to have any risk factors for cancer.
The purpose of some cancer prevention clinical trials is to
find out whether actions people take can prevent cancer. These
may include eating fruits and vegetables, exercising, quitting
smoking, or taking certain medicines, vitamins, minerals, or
New ways to prevent ovarian cancer are being studied in clinical
Clinical trials are taking place in many parts of the country.
Information about clinical trials can be found in the Clinical Trials section of the
NCI Web site.
Check NCI's list of cancer clinical trials
for ovarian cancer prevention trials that are now accepting patients.
Changes to This Summary (12/06/2013)
The PDQcancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Editorial changes were made to this summary.
About This PDQ Summary
Physician Data Query (PDQ) is the National Cancer Institute's (NCI's) comprehensive cancer information database. The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come in two versions. The health professional versions have detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions have cancer information that is accurate and up to date and most versions are also available in Spanish.
PDQ is a service of the NCI. The NCI is part of the National Institutes of Health (NIH). NIH is the federal government’s center of biomedical research. The PDQ summaries are based on an independent review of the medical literature. They are not policy statements of the NCI or the NIH.
Purpose of This Summary
This PDQ cancer information summary has current information about ovarian cancer prevention. It is meant to inform and help patients, families, and caregivers. It does not give formal guidelines or recommendations for making decisions about health care.
Reviewers and Updates
Editorial Boards write the PDQ cancer information summaries and keep them up to date. These Boards are made up of experts in cancer treatment and other specialties related to cancer. The summaries are reviewed regularly and changes are made when there is new information. The date on each summary ("Date Last Modified") is the date of the most recent change.
The information in this patient summary was taken from the health professional version, which is reviewed regularly and updated as needed, by the PDQ Screening and Prevention Editorial Board.
Clinical Trial Information
A clinical trial is a study to answer a scientific question, such as whether one treatment is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. During treatment clinical trials, information is collected about the effects of a new treatment and how well it works. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
Clinical trials are listed in PDQ and can be found online at NCI's Web site. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237).
Permission to Use This Summary
PDQ is a registered trademark. The content of PDQ documents can be used freely as text. It cannot be identified as an NCI PDQ cancer information summary unless the whole summary is shown and it is updated regularly. However, a user would be allowed to write a sentence such as “NCI’s PDQ cancer information summary about breast cancer prevention states the risks in the following way: [include excerpt from the summary].”
The best way to cite this PDQ summary is:
National Cancer Institute: PDQ® Ovarian Cancer Prevention. Bethesda, MD: National Cancer Institute. Date last modified <MM/DD/YYYY>. Available at: http://cancer.gov/cancertopics/pdq/prevention/ovarian/Patient. Accessed <MM/DD/YYYY>.
Images in this summary are used with permission of the author(s), artist, and/or publisher for use in the PDQ summaries only. If you want to use an image from a PDQ summary and you are not using the whole summary, you must get permission from the owner. It cannot be given by the National Cancer Institute. Information about using the images in this summary, along with many other images related to cancer can be found in Visuals Online. Visuals Online is a collection of more than 2,000 scientific images.
The information in these summaries should not be used to make decisions about insurance reimbursement. More information on insurance coverage is available on Cancer.gov on the Coping with Cancer: Financial, Insurance, and Legal Information page.
More information about contacting us or receiving help with the Cancer.gov Web site can be found on our Contact Us for Help page. Questions can also be submitted to Cancer.gov through the Web site’s Contact Form.
Questions or Comments About This Summary
If you have questions or comments about this summary, please send them to Cancer.gov through the Web site’s Contact Form. We can respond only to email messages written in English.
Get More Information From NCI
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 8:00 a.m. to 8:00 p.m., Eastern Time. A trained Cancer Information Specialist is available to answer your questions.
The NCI's LiveHelp® online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 8:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.
Write to us
For more information from the NCI, please write to this address:
- NCI Public Inquiries Office
- 9609 Medical Center Dr.
- Room 2E532 MSC 9760
- Bethesda, MD 20892-9760
Search the NCI Web site
The NCI Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use the search box in the upper right corner of each Web page. The results for a wide range of search terms will include a list of "Best Bets," editorially chosen Web pages that are most closely related to the search term entered.
There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237).