Predictors of Headache Before, During, and After Pregnancy: A Cohort Study

Abstract

The present study endeavored to identify predictors of headache during pregnancy, shortly after delivery, and at 8-week follow-up. Many women suffer from headaches during pregnancy and the post-partum period. However, little is known about factors that predict headache surrounding childbirth. Secondary analysis of longitudinal cohort study of 2434 parturients hospitalized for cesarean or vaginal delivery in 4 university hospitals in the United States and Europe. Data were gathered from interviews and review of medical records shortly after delivery; 972 of the women were contacted 8 weeks later to assess persistent headache. The primary outcome measures were experiencing headache during pregnancy, headache within 72 hours after delivery, and headache at 8 weeks after delivery. Of the parturients, 10% experienced headache during pregnancy, 3.7% within 72 hours after delivery, and 3.6% at 8 weeks postdelivery. Compared to those without a history of headache, a history of headache prior to pregnancy was the strongest predictor of headache during pregnancy (9.8% vs 23.5%; risk ratio 2.4; 95% confidence interval [CI]: 1.4 to 4.0). Experiencing headache during pregnancy (adjusted hazard ratio HR 3.8; 95% CI: 2.4 to 6.2) and receiving needle-based regional anesthesia for pain treatment (adjusted hazard ratio 2.2; 95% CI: 1.1 to 4.5) were independently associated with headache within 72 hours after delivery with event rates of 11.1% and 10.5%, respectively. Compared to those without such a history, headache before pregnancy was significantly associated with experiencing headache 8 weeks after delivery (4.0% vs 23.8%; risk ratio = 6.0; 95% CI: 2.0 to 8.0), but headache during pregnancy or shortly after delivery was not. Several other psychosocial predictors (eg, somatization, smoking before pregnancy) were statistically associated with at least 1 headache outcome. A history of headache prior to pregnancy is a strong predictor of headache during and after pregnancy, the latter independent of but compounded by spinal injection. Physicians should attend to prior headache history when making decisions about pain management during and after childbirth. As the lack of formal International Classification of Headache Disorders, 2nd Edition (ICHD-II), headache diagnoses is a limitation of this study, future longitudinal studies should replicate the present design while including headache subtyping consistent with ICHD-II nosology.