Epidemiologic Reports SurveysA Longitudinal Study to Evaluate Pregnancy-induced Endogenous Analgesia and Pain ModulationCarvalho, Brendan MBBCh, FRCA; Granot, Michal PhD; Sultan, Pervez FRCA; Wilson, Hilary MD; Landau, Ruth MDAuthor Information Department of Anesthesiology, Perioperative and Pain Stanford University Medical Center, Stanford, CA Obstetric Anesthesia Digest: December 2016 - Volume 36 - Issue 4 - p 195-196 doi: 10.1097/01.aoa.0000504723.98838.ac Buy Metrics Abstract (Reg Anesth Pain Med 2016;41:175–180) Pregnancy-induced analgesia has been demonstrated in both animal and human studies, although the latter has yielded mixed results. The authors of the present study thus assessed inhibitory and excitatory pain modulation pathways during each trimester of pregnancy and during the postpartum period in healthy pregnant women. The objectives were to determine if conditioned pain modulation (CPM), mechanical temporal summation (mTS), and temperature-inducing pain 6 of 10 (pain-6) underwent pregnancy-related changes. CPM evaluates descending inhibitory pathways, and mTS evaluates excitatory pathway modulation. The authors hypothesized that there would be an increase in CPM and decrease in mTS during pregnancy, with changes resolving in the postpartum period. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.