Ovarian cancer originates in the cells of the ovaries or related structures like the fallopian tubes. This disease is often detected at advanced stages because early symptoms can be subtle or mistaken for other common conditions. Given the challenges in early detection, understanding and proactively managing the factors that influence risk is a powerful strategy for prevention.
Understanding Non-Modifiable Risk Factors
Certain factors that raise the risk of ovarian cancer are inherent to an individual and cannot be altered. Age is the primary non-modifiable risk factor, with the majority of cancers developing after menopause, typically in women aged 63 or older. The risk increases steeply after age 40.
A family history of ovarian or breast cancer also elevates risk, often linked to inherited changes in specific genes. Mutations in BRCA1 and BRCA2 account for a substantial percentage of hereditary ovarian cancers. Women with a BRCA1 mutation face an estimated lifetime risk between 35% and 70%, while those with a BRCA2 mutation have a risk between 10% and 30%. Other hereditary conditions, like Lynch syndrome (caused by mutations in genes such as MLH1 and MSH2), also increase the lifetime risk for ovarian cancer to about 12%.
Lifestyle Adjustments for Risk Reduction
While genetic and age-related factors are fixed, adopting specific lifestyle adjustments can aid in risk reduction. Maintaining a healthy body weight is important, as being overweight or obese is associated with an increased risk of ovarian cancer. Excess body fat can lead to hormonal imbalances and increased inflammation, which may promote unwanted cell growth.
Dietary choices also play a part, focusing on a diet rich in fruits, vegetables, and whole grains. These foods provide antioxidants and fiber that may help lower cancer risk; limiting processed foods and red meats is also recommended. Avoiding smoking is another behavioral change, as tobacco use is a known risk factor, particularly for the mucinous subtype. Regular physical activity, such as 150 minutes of moderate aerobic activity per week, contributes to weight maintenance and hormonal balance, further supporting a reduced risk.
Medical and Hormonal Protective Measures
Several medical and hormonal factors offer robust protection against ovarian cancer. The use of oral contraceptives is strongly associated with a substantial and long-lasting reduction in risk. This protective effect is duration-dependent: the longer the pills are used, the greater the benefit.
Women who use oral contraceptives for five years or more can see their risk halved, and this reduced risk persists for more than 30 years after stopping the pill. Reproductive history also provides a natural protective effect, as both full-term pregnancy and breastfeeding are linked to a lower risk. Breastfeeding independently reduces the risk of invasive ovarian cancer by about 24%, with the benefit increasing with longer duration.
Common surgical procedures performed for non-cancer reasons, such as tubal ligation and hysterectomy, also lower ovarian cancer risk. Tubal ligation is associated with a 24% lower risk overall. Hysterectomy (removal of the uterus) is linked to a decreased risk of about 20%. Newer evidence suggests that removing the fallopian tubes during a hysterectomy or for sterilization (opportunistic salpingectomy) may provide additional protection, as many ovarian cancers are believed to originate there.
Genetic Counseling and Specialized Prevention
For individuals with a known family history or an identified inherited mutation, specialized testing and surgical options offer the most significant risk reduction. Genetic counseling is the initial step, providing a full risk assessment based on family history. Counseling determines if genetic testing for mutations like BRCA1/2 or Lynch syndrome is appropriate, allowing high-risk individuals to receive a personalized prevention strategy.
The most effective preventative measure for women with BRCA1/2 mutations is the risk-reducing salpingo-oophorectomy (RRSO), which involves the surgical removal of both the ovaries and fallopian tubes. RRSO reduces the risk of ovarian cancer by an estimated 80% to 96% in high-risk carriers. This procedure is typically recommended between the ages of 35 and 40 for BRCA1 carriers, often after childbearing is complete. While RRSO drastically lowers ovarian cancer risk, a small residual risk of primary peritoneal cancer remains.