The results from a 50-year study suggest that women who have irregular periods may be 2.4 times more likely to develop ovarian cancer. The risk appears to be even higher for women with a family history of the disease in a first-degree relative.
The study focused on over 15,000 pregnant women in their mid-20s between 1959 and 1967. Participants provided self-reported information regarding menstrual irregularities. Researchers also examined medical reports. Of these women, 13 percent reported experiencing irregular periods when they were roughly 26 years old.
The study indicates that women whose menstrual cycles lasted 35 days or longer were more than twice as likely to eventually be diagnosed with ovarian cancer. Researchers speculate that a hormonal imbalance in the ovaries known as polycystic ovarian syndrome (PCOS) might be responsible for this increased cancer risk.
“Irregular cycles were correlated with higher risk of death and high grade serious cancer and late-stage cancer,” said study leader Dr. Barbara Cohn, director of the Child Health and Development Studies at the Public Health Institute.
While ovarian cancer is relatively rare, it’s also one of the most deadly types of cancer. A woman’s chance of getting invasive ovarian cancer in her lifetime is about one in 72, according to the American Cancer Society. To put that number in perspective, roughly one in eight women will develop breast cancer in her lifetime.
The biggest hurdle in treating ovarian cancer is early detection. In most cases, the disease isn’t discovered until it’s already too late. There are currently no reliable methods for early diagnosis or screening. And the most common symptoms associated with the condition (like abdominal pain and bloating) typically do not become noticeable until the cancer has become more advanced.
“It’s a desperate situation,” said Cohn. “Ninety percent of all ovarian cancer occurs in women who have no family history.”
The disease is currently the leading cause of reproductive cancer death.
Cohn says the study’s findings are not meant to alarm women who have irregular periods. She notes that the increased average risk is still small because of how rare the cancer is. Even so, she hopes that by better understanding how irregular cycles are correlated with ovarian cancer, researchers might someday find a way to prevent the disease – or at least reduce mortality when it does occur. Cohn noted that since oral contraceptives are associated with lower risk, women may want to consider the possibility of taking them as a prevention strategy, provided there are no other reasons that make hormonal birth control risky.
For the study, irregular menstruation was defined when a woman was unable to predict her next cycle, when a woman’s cycle lasted longer than 35 days, or when there was a mention that a woman was prone to have cycles where she didn’t ovulate.
By Marianne Hayes