Dec. 21, 2019

More than 400,000 hysterectomies ― with or without concurrent bilateral oophorectomy ― are performed each year in the United States, most for benign disease. While studies have shown that bilateral oophorectomy increases the risk of cardiovascular disease and other chronic diseases, there is limited data on the possible harmful long-term outcomes of hysterectomy with ovarian conservation. Today, the rate of ovarian conservation during hysterectomy is increasingly more common, especially for younger women.

Using the Rochester Epidemiology Project records linkage system, Shannon K. Laughlin-Tommaso, M.D., with Gynecology at Mayo Clinic in Rochester, Minnesota, and a team of researchers identified 2,094 women who underwent a hysterectomy with ovarian conservation for benign indications between 1980 and 2002 in Olmsted County, Minnesota. "The aim of this study was to assess the long-term risks of cardiovascular disease and metabolic conditions after hysterectomy with bilateral ovarian conversation compared with population-based, age-matched referent women without a prior hysterectomy or oophorectomy," says Dr. Laughlin-Tommaso.

The research team followed these cohorts to identify 20 chronic conditions related to cardiovascular disease and metabolic conditions. They found that women undergoing hysterectomy with ovarian conservation were more likely to develop hyperlipidemia, hypertension, obesity, cardiac arrhythmias and coronary artery disease. Most striking, researchers found that women who underwent hysterectomy with ovarian conservation at or before age 35 had an increased risk of congestive heart failure (4.6-fold increase) and coronary artery disease (2.5-fold increase).

"In this younger age stratum, the incidence of cardiovascular disease started to diverge in women with hysterectomies compared with referent women 20 to 25 years after the index date, around the time of expected natural menopause," says Dr. Laughlin-Tommaso. "Women who had a hysterectomy with ovarian conservation between ages 36 and 50 years had a 1.3-fold increased risk of coronary artery disease, which is estimated to be a 6% increase in absolute risk."

Dr. Laughlin-Tommaso notes that women who had hysterectomies after the age of 50 did not appear to have an increased risk of cardiovascular disease and metabolic conditions.

"The uterus may not directly impact the cardiovascular system, but the increased risk of cardiovascular disease effects could be mediated by the effects on the ovaries," says Dr. Laughlin-Tommaso. "One theory is that the loss of collateral blood flow to the ovaries caused by a hysterectomy results in decreased ovarian reserve and its sequelae. Or the uterus itself could have a direct, unknown effect on the ovaries."

Researchers say this study overcomes several limitations of prior studies, including the fact that they could detect more cardiovascular disease events compared with other studies in which the follow-up was limited to 10 or fewer years. "The length of follow-up is critical because hysterectomies occur in relatively younger women, but cardiovascular disease increases with age," Dr. Laughlin-Tommaso says. "The curves for cardiovascular disease outcomes start to diverge only 10, 15 or 20 years after hysterectomy."

Even with ovarian conservation, hysterectomies are associated with an increased long-term risk of cardiovascular and metabolic conditions, especially in women who undergo hysterectomy before the age of 35.

"We believe that the increased risk could be mediated through impaired ovarian function secondary to surgery," Dr. Laughlin-Tommaso says. "And from a clinical perspective, uterine-preserving treatments for heavy menstrual bleeding or fibroids should be considered. For women who need to undergo a hysterectomy, hormonal treatment should be considered even with conservation of the ovaries." In a subsample of 792 women who underwent hysterectomy with known hormonal status, less than a quarter of the women used estrogen.

Study results were published in Menopause in 2018.

For more information

Rochester Epidemiology Project.

Laughlin-Tommaso SK, et al. Cardiovascular and metabolic morbidity after hysterectomy with ovarian conservation: A cohort study. Menopause. 2018;25:483.