Background There are suggestions that the use of herbal medicine during pregnancy is associated with adverse pregnancy outcomes. However, the extent of use, the reasons for use and the link between use and poor outcomes have not been rigorously studied. So, my PhD research examined associations between the use of herbal medicine during pregnancy and adverse maternal and neonatal outcomes. It also explored the socio-cultural explanations of the pregnancy-related problems and how this influences the use of herbal medicine. Methods The PhD research project comprised of four sub-studies. The first was a systematic review and meta-analysis of the effectiveness, safety and prevalence of herbal medicines during pregnancy at global and regional (sub-Saharan Africa) levels. The second was a secondary analysis of Cluster-randomised controlled trial data from Malawi. For this analysis, I examined the link between herbal medicine use and adverse pregnancy outcomes amongst 32,254 births recorded from 2005 to 2010 in Mchinji. The other two sub-studies were part of a field-based ‘exploratory sequential mixed-methods study’ in Malawi. I first conducted a qualitative study involving semi-structured interviews with women who had recently (<24 months) given birth (n=10) and focus group discussions with grandmothers or traditional birth attendants (n=2) and community health workers (n=2). This was followed by a hospital-based case-cohort study with 1,830 women (15-49 years old) who had just given birth. The motives for herbal medicine use and the associations between herbal medicine use and pregnancy outcomes were assessed. Results Multiple explanations of pregnancy complications were identified, and most of them are grounded in cultural beliefs. Specifically, most pregnancy problems were attributed to witchcraft and associated supernatural forces. The findings further show that the explanations of pregnancy problems influence the choice of practitioners and care-seeking practices, including the use of herbal medicine. Herbal medicine use during pregnancy is high in both Malawi and other sub-Saharan countries. I also found that some of the herbal medicines were associated with adverse maternal and neonatal outcomes (e.g. pre-labour rupture of membranes and neonatal death) while others were not. Conclusion There appear to be mixed-effects of herbal medicines during pregnancy. Some were associated with adverse pregnancy outcomes whereas others were not. Because it is not yet clear as to which herbal medicines are safe or not, the key recommendation from this thesis is that where possible all herbal medicines of unproven safety should be avoided during pregnancy
