Trajectories of pain during pregnancy predict symptoms of postpartum depression

Introduction: Postpartum depression imparts a significant and long-lasting burden on maternal and child health. Successful prevention or early detection of postpartum depression will rely on the identification of early risk factors. Pain during pregnancy (before childbirth) is a key potential predictor of postpartum depression risk. However, longitudinal studies characterizing pregnancy pain, its normal trajectory over time, and its prospective relations with symptoms of postpartum depression are lacking. Methods: We used data from a longitudinal study of maternal emotion that included assessments of pain and depressive symptoms at 3 time points-during the second and third trimester of pregnancy and at 4 months postpartum. Structural equation modelling was used to estimate longitudinal patterns of change in maternal pain over time. Latent growth curve parameters were tested as predictors of symptoms of postpartum depression. Results: Ninety-three healthy pregnant women enrolled in this study. Although the sample comprised women with relatively low-risk pregnancies, more than 90% of participants experienced pregnancy pain. Greater linear increases and less negative quadratic change in maternal pain over time were associated with greater levels of postpartum depression, even when controlling for prenatal depressive symptoms. Interpreting both parameters together, pain that increased in late pregnancy, when normative patterns had either levelled off or begun to decline, was associated with greater levels of postpartum depression. Conclusion: A developmental trajectory of pain experience that did not subside after childbirth was associated with greater postpartum depressive symptoms, suggesting that atypical trajectories of pain may be a risk factor for postpartum depression.