Hormonal and clinical predictors for post-egg retrieval pain in women undergoing assisted reproductive technology procedures

Objectives: The intensity of post-egg retrieval pain is underestimated, with few studies examining postprocedural pain and predictors to identify women at risk for severe pain. We evaluated the influence of preprocedural hormonal levels, ovarian factors, and mechanical temporal summation (mTS) as predictors for post-egg retrieval pain in women undergoing in vitro fertilization. Methods: Eighteen women scheduled for ultrasound-guided egg retrieval under standardized anesthesia and postprocedural analgesia were enrolled. Preprocedural mTS, questionnaires, clinical data related to anesthesia and the procedure itself, postprocedural pain scores, and pain medication for breakthrough pain were recorded. Statistical analysis included Pearson product-moment correlations, Mann-Whitney U tests, and multiple linear regressions. Results: Average peak post-egg retrieval pain during the first 24 hours was 5.0±1.6 on a numerical response scale (0=no pain, 10=worst pain imaginable). Peak post-egg retrieval pain was correlated with basal antimullerian hormone (AMH) (r=0.549, P=0.018), preprocedural peak estradiol (r=0.582, P=0.011), total number of follicles (r=0.517, P=0.028), and number of retrieved eggs (r=0.510, P=0.031). Ovarian hyperstimulation syndrome (n=4) was associated with higher basal AMH (P=0.004), higher peak pain scores (P=0.049), but not with peak estradiol (P=0.13). The mTS did not correlate with peak postprocedural pain (r=0.266, P=0.286), or peak estradiol level (r=0.090, P=0.899). Discussion: Peak post-egg retrieval pain intensity was higher than anticipated. Our results suggest that post-egg retrieval pain can be predicted by baseline AMH, high peak estradiol, and ovarian hyperstimulation syndrome. Further studies to evaluate intraprocedural and postprocedural pain in this population are needed, as well as clinical trials to assess postprocedural analgesia in women presenting with high hormonal levels.