The association of pain and psychological vulnerabilities with postpartum pain catastrophizing: a secondary analysis of a randomized controlled trial.

Objective: Pain catastrophizing is an amplified negative thought process that emerges during actual or perceived pain moments. There is limited information on the role of labour pain in the development of pain catastrophizing during the postpartum period. We sought to investigate whether labour pain, pain, and psychological vulnerabilities are associated with high pain catastrophizing (defined as a Pain Catastrophizing Scale [PCS] ≥ 25) at 6-10 weeks postpartum. Methods: We conducted a secondary analysis of a randomized controlled trial that recruited pregnant individuals at term prior to labour and delivery. Participants filled in the predelivery questionnaires on labour pain, pain, and psychological vulnerabilities upon written consent. The recruited parturients also completed an online survey 6-10 weeks postpartum to determine the status of pain catastrophizing. Results: Among the 820 parturients who completed the postpartum online survey, 116 (14.4%) were high pain catastrophizing. Multivariate logistic regression analysis found that greater enormity of labour pain (adjusted odds ratio [aOR], 1.04; 95% confidence interval [CI], 1.02 to 1.06), choosing nonepidural over epidural analgesia (aOR, 1.84; 95% CI, 1.17 to 2.91), having a family history of other mental disorders (aOR, 31.3; 95% CI, 5.7 to 173.7), greater predelivery pain catastrophizing (aOR, 2.70; 95% CI, 1.68 to 4.36), greater predelivery activity avoidance (aOR, 1.06; 95% CI, 1.04 to 1.09), and greater predelivery state anxiety (aOR, 1.03; 95% CI, 1.01 to 1.05) were associated with postpartum pain catastrophizing at 6-10 weeks postpartum. Having greater infant weight was protective against the risk of postpartum pain catastrophizing (aOR, 0.43; 95% CI, 0.23 to 0.78). The area under the curve of the generated multivariable model was 0.82 (95% CI, 0.78 to 0.86). Conclusions: Predelivery pain and psychological vulnerabilities were associated with postpartum pain catastrophizing among healthy parturients undergoing labour. Future prospective studies are needed to evaluate whether such risk factors can allow earlier intervention to reduce pain catastrophizing.

Background: ClinicalTrials.gov ( NCT03167905 ); first submitted 30 May 2017.