Headache and adverse pregnancy outcomes: a prospective study.

OBJECTIVE: To investigate the association between headache, namely migraine and tension-type headache, and adverse pregnancy outcome. STUDY DESIGN: Prospective cohort study conducted in three tertiary care centres in Italy: 376 pregnant women suffering from headache and 326 non-headache pregnant women as controls were recruited. The diagnosis of headache was made at the beginning of pregnancy, according to the criteria of the International Classification of Headache Disorders (ICHD-II). Women were followed up until delivery, and gestational age at delivery, mode of delivery, indications for operative delivery or caesarean section, birth weight, and centile of neonatal weight at birth were carefully recorded. Main outcome measures of the study were: preterm delivery, newborns small for gestational age, and foetal losses. Odds ratios and 95% confidence intervals were calculated. RESULTS: The incidence of preterm delivery (Adj OR, 95% CI 2.74, 1.27-5.91) was significantly higher in women suffering from headache than in controls. There was no statistically significant difference in small for gestational age newborns between the groups. Fewer women in the headache group had preterm elective caesarean section or induction of labour, than did controls, indicating a higher chance of spontaneous preterm delivery. Multivariate analysis showed that the association between headache, either migraine or tension-type, and adverse perinatal outcomes was statistically significant regardless of pre-eclampsia. CONCLUSIONS: Women with headache should be considered at risk for adverse perinatal outcomes and should, therefore, be included in a high-risk pregnancy protocol of care throughout pregnancy.