Introduction: Previous studies have shown that echinacea is among the most widely used herbal medicines during pregnancy in Western countries. Despite its frequent use, we know little about the safety of this herbal medicine during pregnancy. The primary aim of this study was to study the consequences of the use of echinacea on malformations and common adverse pregnancy outcomes. Secondly, we aimed to characterize women using this herb in pregnancy.
Method: This study is based on the Norwegian Mother and Child Cohort Study (MoBa) and included 68,522 women and their children. Information was retrieved from three self-administered questionnaires completed by the women in pregnancy weeks 17 and 30 and 6 months after birth. Information on pregnancy outcomes was retrieved from the Medical Birth Registry of Norway. Generalized estimating equations analyses were performed to assess the association between exposure to echinacea and pregnancy outcomes. Pearson's chi-square test was used to assess factors related to use of echinacea in pregnancy.
Results: Among 68,522 women, 363 (0.5 %) reported the use of echinacea during pregnancy. These women were characterized by high age and delivery before 2002 and were to a less extent smoking in pregnancy. The use of echinacea was not associated with an increased risk of malformations or adverse pregnancy outcomes.
Conclusion: This study revealed no increased risk of malformations or adverse pregnancy outcomes after the use of echinacea in pregnancy. Studies on the safety of commonly used herbal medications are important to identify herbals that should be avoided in pregnancy.
Keywords: Echinacea; Herbal medicine; MoBa; Pregnancy.