P-335 FERTIPAIN study: An international web survey on pain experience after in vitro fertilization in women with endometriosis

Abstract Study question Does in vitro fertilization (IVF) affects endometriosis pain symptoms in patients with endometriosis and what factors influence pain experience? Summary answer IVF worsened pelvic pain in 52% of women. rASRM endometriosis stage was not significant, highlighting the need for tailored pain management and holistic support. What is known already Endometriosis affects ∼30% of subfertile women, many of whom require IVF to conceive. Beyond subfertility, it causes debilitating pelvic pain, including dysmenorrhea, dyspareunia, and chronic pain, significantly impairing quality of life. While IVF improves reproductive outcomes, its impact on pain remains uncertain. Some qualitative studies report pain exacerbation during and after IVF, particularly during ovarian stimulation and oocyte retrieval, while others show no significant long-term changes. Psychological stress and inadequate pain management further contribute to patient distress. Satisfaction with medical care, including effective counseling and tailored pain management strategies, may influence patient-reported outcomes. Study design, size, duration The FertiPain study is an international online survey assessing the pain experience of women with endometriosis undergoing IVF. It consists of 25 multiple-choice questions and has been translated into seven languages. Recruitment was conducted through patient advocacy organizations in multiple countries and via social media. Data are collected anonymously through REDCap, ensuring confidentiality and secure storage in compliance with European data regulations. The study, ongoing since September 2024, includes 539 respondents in this preliminary analysis. Participants/materials, setting, methods Eligible participants were women aged ≥18 years, diagnosed with endometriosis, and having undergone at least one IVF cycle. Statistical analyses included descriptive statistics, Mann-Whitney U tests, and Chi² tests. Multivariate ordinal logistic regression identified factors associated with pain evolution, with VIF assessing multicollinearity and adjustments for confounders. Longitudinal pain trajectories across IVF cycles were analyzed using RM-ANOVA to assess within-subject variations over time. Main results and the role of chance 539 participants (median age 36 years [IQR: 8.5], 79% European) were analyzed, including 1,134 oocyte retrievals and 1,773 embryo transfers. The median time since IVF was 1 year (IQR: 4.5). A live birth was achieved by 37%, while the miscarriage rate was 19%. Among participants, 52% reported worsening pelvic pain, 80% experienced increased dysmenorrhea, and 41% reported aggravated dyspareunia after IVF. Live birth was associated with a lower likelihood of pain worsening (OR = 0.53, 95% CI [0.38–0.75], p < 0.001) and a positive influence on mood (OR = 1.55, 95% CI [1.14–2.12], p = 0.005). Bladder pain syndrome was the strongest predictor of pain worsening (OR = 3.08, 95% CI [1.18–8.01], p = 0.021). However, deep endometriosis (OR = 1.47, 95% CI [0.87–2.50], p = 0.150), prior endometriosis surgery before IVF (OR = 0.96, 95% CI [0.49–1.87], p = 0.903), and the number of IVF cycles (OR = 0.99, 95% CI [0.86–1.13], p = 0.843) were not significantly associated with worsened pain. However, 45.1% of women were dissatisfied with pain management, during the IVF journey and 31% underwent surgery following IVF. Limitations, reasons for caution As this study relies on self-reported data from an online survey, response bias cannot be excluded. The sample is predominantly composed of highly educated participants, with a potential overrepresentation of less satisfied patients, limiting the robustness and generalizability of the findings. Wider implications of the findings The IVF journey may worsen pain in women with endometriosis. Chronic pelvic pain comorbidities before IVF impact pain more than the type or anatomical severity of the disease. Tailored pain management and counseling during IVF could reduce patient dissatisfaction, improving overall experience and quality of life. Trial registration number No