Pain after oocyte retrieval in women with endometriosis undergoing fertility preservation or IVF

Do women with endometriosis undergoing oocyte retrieval for fertility preservation experience the same level of pain as women undergoing oocyte retrieval for IVF?

This retrospective cohort study included 796 cycles in women with endometriosis undergoing oocyte retrieval for fertility preservation (n = 401) or IVF (n = 395) between January 2020 and October 2022. Post-operative pain assessments were compared between the two groups using a numeric rating scale (NRS).

Women in the fertility preservation group were younger (32.1 ± 4.2 years versus 35.1 ± 4.1 years; P < 0.001), had a lower body mass index (22.8 ± 3.9 kg/m² versus 24.6 ± 4.4 kg/m²; P < 0.001) and had a lower concentration of anti-Müllerian hormone (1.8 ± 1.5 ng/ml versus 2.15 ± 2.11 ng/ml; P = 0.026) in comparison with women in the IVF group. The oestrogen concentration on the day of ovulation trigger was higher in women in the fertility preservation group (2188 ± 1152 pg/ml versus 2081 ± 995 pg/ml; P = 0.004), and the prevalence rates of adenomyosis and digestive endometrial lesions were lower in women in the fertility preservation group (14% versus 29%, P < 0.001; 16% versus 25%, P = 0.003, respectively) compared with women in the IVF group. After oocyte puncture, more women in the fertility preservation group had an NRS pain score >3 (moderate to severe pain) compared with women in the IVF group (20% versus 14%; P = 0.018). The progestin-primed ovarian stimulation (PPOS) protocol was identified as an independent predictive factor of greater post-operative pain (adjusted OR 2.30, 95% CI 1.06-5.15; P = 0.039).

Women with endometriosis undergoing fertility preservation reported more intense post-operative pain in the recovery room than women undergoing IVF. The PPOS protocol was an independent risk factor of intense pain (NRS pain score >3) in women with endometriosis, but further studies are needed to confirm this result.