Ovary Removal Before Menopause Can Have Lasting Health Consequences, Study Finds

A new study found that a surgical procedure that removes both ovaries can lead to long-term health complications in people who have not yet gone through menopause.

Surgeons commonly perform this procedure, called a premenopausal bilateral oophorectomy (PBO), as part of a hysterectomy. They may also recommend it to reduce the risk of ovarian cancer in high-risk people.

But a growing number of experts warn that in individuals who are not at high risk for ovarian cancer, ovary removal before menopause is often unnecessary and can cause lasting health issues.

The goal of the new research is “to position women to have greater power over their health and the ability to weigh the pros and cons of having their ovaries removed,” says the study’s lead author, Michelle Mielke, PhD, a professor of epidemiology and prevention at the Wake Forest School of Medicine in Winston-Salem, North Carolina.

She adds that the risk-benefit discussion will be different for women who face higher odds of ovarian cancer.

Researchers Warn of ‘Detrimental’ Effects

In the study, published September 13, 2023, in the journal Menopause, Dr. Mielke and her team compared medical records and cognitive tests of more than 500 women living in the same county in Minnesota. About half had undergone a PBO with or without hysterectomy; the other half had not.

The median age of the women who’d undergone PBO was 67 years; on average, they’d had the procedure at least 22 years before the start of the study. The participants who still had their ovaries were at least 55 years old.

The researchers found that subjects who had both ovaries removed before age 46 were more likely to have arthritis, asthma, obstructive sleep apnea, and bone fractures. Those who’d had a PBO between ages 46 and 49 years had a higher rate of arthritis and obstructive sleep apnea.

The researchers did not find any differences in cognitive function between those who’d had their ovaries removed and those who had not, nor between the different ages included in the PBO group.

While not all of the health issues may be related to PBO, “we have known for generations that removing a woman’s ovaries pre-menopause is incredibly detrimental for many different areas, including how the heart and bones work,” says Elena Ratner, MD, a professor of obstetrics, gynecology, and reproductive sciences and the co-chief of the section of gynecologic oncology at Yale University School of Medicine in New Haven, Connecticut, who was not involved in the new study.

“But there are certain populations of women where we take that detriment in order to decrease their risk of ovarian cancer,” she adds.

Ovary Removal Is Common With Hysterectomy

Aside from cancer prevention or birth control, a woman may opt to have a hysterectomy if she has uterine fibroids or uterine prolapse, endometriosis or adenomyosis, or heavy or unusual vaginal bleeding, says the Office on Women’s Health at the U.S. Department of Health and Human Services.

According to Yale Medicine, hysterectomy is the second most common surgery for women — cesarean section is the most common — and about a half million hysterectomies are performed every year. The study authors estimate that one-quarter of women ages 40 to 44 and nearly half of women aged 45 to 59 years who’ve undergone a hysterectomy have had their ovaries removed.

“Removing the ovaries during a hysterectomy has been a common procedure,” Mielke says. “Now research is suggesting we want to reconsider that. If patients have a hysterectomy, we may want to leave the ovaries.”

Why Does Ovary Removal Affect Heart and Bones?

In addition to making and storing eggs, the ovaries produce the vital hormones estrogen, progesterone, and even small amounts of testosterone. These hormones not only control the menstrual cycle and pregnancy, but have far-reaching roles throughout the body, particularly related to the cardiovascular system and the bones.

Loss of estrogen triggers a rapid loss in bone density, according to the American College of Obstetricians and Gynecologists (ACOG). The hormone also has a protective effect on the cardiovascular system, ACOG states.

Plummeting estrogen is one reason natural menopause has been linked to higher rates of cardiovascular disease and osteoporosis. Surgical menopause — menopause induced by the removal of the ovaries, often before natural menopause would normally start — appears to have an even bigger effect.

“When you go through menopause there is a slow decline in hormones, but when you have PBO or hysterectomy, it’s this shock, this sudden drop,” Mielke says.

A Danish study of more than 285,000 women in Denmark, published in May 2023 in the journal Annals of Internal Medicine, found that women who’d had their ovaries removed before age 45 were more likely to be hospitalized for cardiovascular disease than women who still had their ovaries and those who had them removed later in life. These women also had a higher 10-year cumulative risk for hospitalization for cardiovascular disease. They also had a higher overall risk for cancer past age 45, although their (average) ovarian cancer risk dropped.

People at High Risk of Ovarian Cancer Have a Unique Calculation to Make

For anyone at high risk of ovarian cancer, the decision about whether to have their ovaries removed before menopause as a preventive measure involves balancing the pros and cons.

“Ovarian cancer remains very deadly because women typically get diagnosed at advanced stages. We fail to detect these cancers early — and that’s not for lack of trying,” Mielke says.

Both Mielke and Dr. Ratner say ovarian cancer is very difficult to detect on an ultrasound, and there isn’t an effective test, such as a blood test, for the cancer. For these reasons, prevention has long been the best option.

Mielke says she encourages all women to get genetic testing done to screen for mutations that put them at higher risk for ovarian cancer. From there, they can better assess their options, she says.

Removing the ovaries or just, potentially, the fallopian tubes (which connect the ovaries to the uterus) can be the right decision for people who are at high risk for ovarian cancer, including those with genetic mutations such as BRCA or a family history of cervical cancer, says Ratner.

“A lot of ovarian cancers are actually fallopian tube cancers,” says Ratner. And since the only function they have is to facilitate natural conception, removing the uterus and fallopian tubes, but not the ovaries, in a woman who does not plan to get pregnant is another option that both reduces risk of cancer and keeps the ovaries intact.

Hormone therapy can help negate some of the effects of PBO if that is the best option for someone who is at high risk for cervical cancer or who has another condition that makes ovary removal necessary, says Ratner.

“For women who are, indeed, at high risk for ovarian cancer, we do recommend ovary removal,” she says.