Endometriosis can complicate hysterectomies, study shows

Patients with endometriosis are more likely to experience complications during and after hysterectomies, a study by UT Southwestern Medical Center researchers shows. The findings, published in the Journal of Minimally Invasive Gynecology, suggest surgeons should be prepared for the problems that may occur in patients with endometriosis, a painful condition that affects about 15% of women and is a major cause of infertility.

"This study affirms what many of us in gynecology and surgery have known but needed large numbers of surgical cases to substantiate: that patients with endometriosis are at increased risk of complications if they have a hysterectomy," said study leader Kimberly Kho, M.D., M.P.H., Professor of Obstetrics and Gynecology, Associate Chief of Gynecology, and Director of the Fellowship in Minimally Invasive Gynecologic Surgery at UT Southwestern.

Approximately 600,000 hysterectomies are performed every year in the U.S., according to the Centers for Disease Control and Prevention, making it the second-most common surgery for women behind cesarean sections. The procedure, in which the uterus is removed, is performed for a variety of reasons, including to treat cancer, remove noncancerous growths called fibroids, and treat uterine prolapse, in which pelvic floor muscles and ligaments fail to support the uterus.

Symptoms of endometriosis, in which tissue similar to the uterine lining grows outside the womb, frequently result in hysterectomy, Dr. Kho explained. Anecdotal evidence and smaller studies have suggested the presence of endometriosis—even when this condition alone isn't treated with a hysterectomy—can cause complications when the procedure is performed for other reasons. However, this phenomenon has not been fully investigated on a large scale, she said.

To better understand complications associated with hysterectomies and endometriosis, Dr. Kho and her colleagues used data from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database. With contributions from more than 700 U.S. hospital sites, the database contains information on over 150 variables that describe preoperative, intraoperative, and 30-day postoperative outcomes for patients undergoing major outpatient and inpatient surgeries.

The researchers identified 127,556 hysterectomies between Jan. 1, 2014, and Dec. 31, 2019, for reasons other than cancer. Of these, 19,618, or about 15.4%, were associated with endometriosis that had either been diagnosed before surgery or recognized during surgery.

When Dr. Kho and her team compared outcomes for patients with endometriosis to those without, they found the incidence of all postoperative complications was about 1.7% higher—a modest but significant increase. This number included not only minor complications such as urinary tract and wound infections, but also major ones such as sepsis, blood transfusions, and postoperative readmissions.

Additionally, patients with endometriosis were more likely to have longer procedures and need other surgical procedures at the time of their hysterectomy, including operations to remove adhesions caused by the endometriotic tissue, gastrointestinal surgeries such as appendectomies or bowel resections, and surgeries affecting structures around the uterus, such as the ovaries, fallopian tubes, and pelvic floor ligaments.

Dr. Kho noted that current training for gynecological surgeons in the U.S. often underestimates the time and skill necessary to care for patients with endometriosis, particularly when this condition is not anticipated prior to surgery, or the degree of endometriosis is not predicted preoperatively.

"These data support the need for preoperative diagnostic tools to be able to anticipate and plan for complex endometriosis surgeries so that neither patients nor surgeons are surprised or unprepared for the complexity of a procedure when they are in the operating room," she said. "We also need to ensure that surgeons have the requisite skills and are prepared to deal with these often complex cases."