The association between labour epidural analgesia and postpartum depressive symptoms: a longitudinal cohort study.

Background: Pain is a risk factor for postpartum depression (PPD) and labour epidural analgesia (LEA) may lower the incidence of PPD. We evaluated depressive symptoms risk at three, six, and 12 months postpartum in women with LEA compared with women without LEA.

Methods: With ethics approval, hypotheses were tested using data from a longitudinal prospective observational cohort study between January 2015 and January 2019 in nulliparous women aged ≥ 18 yr with uncomplicated, singleton pregnancies. Email surveys were completed at baseline (18-20 weeks' gestation) and at three-, six- and 12 months postpartum, including the Edinburgh Postpartum Depression Scale (EPDS). Maternal, infant, and anesthesia characteristics were abstracted from electronic databases. The EPDS scores at three, six, and 12 months postpartum were analyzed using generalized estimating equations with and without covariates.

Results: Of the 909 women who consented to participate, 709 women were included in the study. Antenatal EPDS scores, not LEA, predicted postpartum depressive symptom risk (P < 0.001). The adjusted 95% confidence intervals suggest mean EPDS scores differ from 1.0 point lower in the LEA group at 12 months to 1.5 points higher in the no LEA group at three months on its 0-30 scale. All the confidence intervals included zero at three, six, and 12 months, so were considered non-significant (P > 0.05).

Conclusion: This study did not identify an association between LEA and risk of depressive symptoms postpartum, although small mean differences between groups cannot be ruled out. Future studies should focus on other modifiable variables that influence the development of PPD.