Hysterectomy for endometriosis with or without ovarian preservation in British Columbia, Canada : a population based retrospective cohort study of post surgical outcomes

BACKGROUND: More research is needed comparing post-surgical outcomes between patients who undergo hysterectomy for endometriosis with or without ovarian conservation. OBJECTIVE: To compare the rate of reoperation and use of other pain-related health services after hysterectomy for endometriosis, with or without ovarian conservation METHODS: A population-based retrospective cohort study of 4489 patients aged 19-50 in British Columbia, Canada, undergoing hysterectomy for endometriosis between 2001 and 2016. Index surgeries were classified as: hysterectomy alone (conservation of both ovaries), hysterectomy with unilateral salpingoophorectomy (USO), or hysterectomy with bilateral salpingoophorectomy (BSO). Reoperation rate was the primary outcome. Secondary outcomes (measured at 3-12 months and 1-5 years after hysterectomy) included: physician visits for endometriosis and pelvic pain, prescriptions filled for opioids and hormonal suppression medications and hormone replacement therapy (HRT). RESULTS: 89.5% of patients remained reoperation free by the end of follow-up (median of 10 years, IQR = 6.1 to 14.3 years). Patients undergoing hysterectomy alone were more likely to undergo at least one reoperation compared to those having hysterectomy with BSO (13% vs 5%, p<0.0001), most commonly oophorectomy and adhesiolysis. When oophorectomy as reoperation was removed in a sensitivity analysis, this difference was attenuated. Secondary outcomes including physician visits for endometriosis or pelvic pain and rates of opioid prescriptions filled were similar between groups. The rate of prescriptions filled for hormonal suppression medications was low for all groups. The rate of prescriptions filled for HRT after hysterectomy with BSO was suboptimal - 60.6% filling at least one prescription at 3-12 months after index surgery. CONCLUSION: Patients who underwent hysterectomy with BSO had a lower reoperation rate than those who had hysterectomy with conservation of one or both ovaries. However, there was little difference between the groups for the secondary outcomes measured, suggesting that persistent pelvic pain after hysterectomy for endometriosis may not differ significantly based on ovarian conservation status. Moreover, HRT use after hysterectomy with BSO was suboptimal, which may have significant health consequences for these individuals undergoing premature surgical menopause. Therefore, strong consideration should be given to ovarian conservation at the time of hysterectomy for endometriosis.