Introduction and hypothesis
The aim of this study was to investigate whether the indication for hysterectomy was itself a risk factor for subsequent pelvic organ prolapse (POP) in Danish women who underwent hysterectomy from 1977 to 2009.
Methods
Data from 154,882 women who underwent hysterectomy for benign conditions during the period 1977 – 2009 were extracted from the Danish National Patient Register. Patients were followed up from hysterectomy to POP surgery, death/emigration, or end of study period. Hazard ratios (HR) for the first POP surgery in each woman were calculated using the Cox proportional hazards model. Survival analysis for each indication for hysterectomy was performed using the Kaplan-Meier product limit method.
Results
Fibroids/polyps as the indication was used as the reference when calculating HRs. After adjustment for calendar period, patient age, and hysterectomy route, the HR for POP was 6.57 (95 % confidence interval 5.91 – 7.30). The HR for abnormal uterine bleeding (AUB), pain, endometriosis, and “other indications” was significantly higher than the reference. POP surgery was performed predominantly in the posterior compartment for all indications except benign ovarian tumors.
Conclusions
POP as the indication for hysterectomy was associated with the highest cumulative incidence of subsequent POP surgery 32 years after hysterectomy. But the indications AUB, pain, endometriosis, and “other indications” were associated with a higher risk of subsequent POP surgery after hysterectomy than the indication fibroids/polyps. The predominant compartment for POP surgery was the posterior compartment for almost all indications. The indication for hysterectomy and the compartment in which POP surgery was performed subsequent to hysterectomy were associated.