The incidence of hysterectomies for benign gynecologic conditions dropped 17.6% from 1991 through 2004 (P<0.001) just as changes in practice and shorter hospital stays were associated with fewer associated complications (P<0.001), Lloyd H. Smith, M.D., Ph.D., of the University of California Davis, and colleagues wrote in the September issue of Obstetrics & Gynecology.

Clinical and technical innovations provided less invasive alternatives to hysterectomy in the early 1990s, the researchers wrote. Procedures such as endometrial ablation for benign uterine conditions increased between 1990 and 1997, for example. At the same time, laparoscopically assisted vaginal hysterectomy became increasingly popular.

To assess the frequency and safety of hysterectomy, the researchers analyzed data on 649,758 women undergoing inpatient hysterectomy in California from 1991 through 2004 from the California Patient Discharge Database.

The incidence of laparoscopically assisted vaginal hysterectomy increased 12-fold, from 0.3 per 10,000 women per year in 1991 to 3.6 per 10,000 women per year in 1997, although incidence of the procedure declined to 3.0 per 10,000 women per year in 2004.

Study authors also said they found evidence of a learning curve by analyzing complications associated with laparoscopically assisted vaginal hysterectomy during its widespread introduction in California. Learning the procedure became mandatory in residency programs in the U.S., and newly trained surgeons entered practice with more experience in this procedure, study authors wrote.

There was also a significant 38.8% reduction (P<0.001) in the rate of total abdominal hysterectomy over the study period, while the incidence of subtotal hysterectomy jumped 17-fold. This was likely because of a perception that subtotal hysterectomy was associated with less risk of urinary incontinence and sexual dysfunction, the authors said.

Upgrades in surgical equipment or technique, and prevention of infection and venous thromboembolism, have improved the safety of hysterectomy, the researchers said. Combined with shorter hospital stays, these factors likely explain the decrease in complications such as bleeding and urinary or GI tract problems.

After controlling for several factors such as age, race, and comorbidities, the year that a patient had a hysterectomy was associated with reduced odds of medical and surgical complications.

For example, there was an increased risk of a urinary tract complication in 1995-1996 for patients undergoing laparoscopically assisted vaginal hysterectomy (OR 1.41, 95% CI 1.10 to 1.18), vaginal hysterectomy (OR 1.18, 95% CI 1.08 to 1.29), or total abdominal hysterectomy (OR 1.12, 95% CI 1.06 to 1.17), but that risk subsequently declined. Also, gastrointestinal tract complications peaked in the mid-1990s for the three procedures and then declined.

Researchers found statistically significant declines in the odds of bleeding complications for all hysterectomy types except total abdominal hysterectomy.

The length of hospital stay also decreased for each type of hysterectomy. Stays for laparoscopically assisted vaginal hysterectomy and vaginal hysterectomy dropped to two days from three, total abdominal hysterectomy to three days from four, and subtotal hysterectomy to two days from four.

Certain factors, however, were associated with an increased risk for complications: older age, African-American race, and the presence of comorbidities.

A primary diagnosis of fibroids was associated with higher odds of complications than other primary diagnoses, save for a primary diagnosis of infection, which was associated with the highest risk of surgical complications in total abdominal hysterectomy or subtotal hysterectomy.

Concurrent vaginal repair or urinary incontinence procedures were associated with the highest risk of urinary tract complications. For example, the odds of urinary tract injury associated with concurrent vaginal repair was elevated for laparoscopically assisted vaginal hysterectomy (OR 1.46, 95% CI 1.26 to 1.69), vaginal hysterectomy (OR 1.55, 95% CI 1.44 to 1.67), and total abdominal hysterectomy (OR 1.21, 95% CI 1.14 to 1.29). And the odds of urinary tract injury associated with concurrent urinary incontinence procedure were elevated for laparoscopically assisted vaginal hysterectomy (OR 1.24, 95% CI 1.04 to 1.48), vaginal hysterectomy (OR 1.34, 95% CI 1.25 to 1.43), and total abdominal hysterectomy (OR 1.25, 95% CI 1.18 to 1.32)

African-American race was associated with elevated odds of almost every category of medical and surgical complication compared with non-Hispanic whites. The study authors wrote that this disparity in outcomes warrants further study.

The authors acknowledged some limitations of the study, including that they were unable to analyze cases of hysterectomy that may have occurred in the outpatient setting in freestanding surgical centers, therefore possibly underestimating rates of hysterectomy in California. Also, the use of complication codes to analyze postoperative clinical outcomes might be limiting.