The Use of Ginger Bioactive Compounds in Pregnancy: An Evidence Scan and Umbrella Review of Existing Meta-Analyses

Ginger is a commonly used nonpharmacological treatment of pregnancy-related symptoms including nausea and vomiting, inflammation, and gastrointestinal dysfunction. Determining the efficacy of ginger is particularly important during pregnancy and lactation when maternal and neonatal detrimental effects may be a concern. This evidence scan and umbrella review aimed to assess the extent and quality of the evidence regarding the effectiveness and safety of using dietary preparations of ginger during pregnancy and lactation. We searched MEDLINE, Embase, CAB Abstracts, and International Pharmaceutical Abstracts up to 20 December, 2023, to identify maternal and neonatal outcomes associated with ginger use during pregnancy or lactation compared to placebo or conventional medicines. Outcomes for which a meta-analysis (MA) of intervention studies was identified were synthesized in an umbrella review. The AMSTAR-2 (A MeaSurement Tool to Assess systematic Reviews-2) tool was used to critically appraise the reviews. The percent overlap in primary studies was calculated overall and pairwise for each included MA. Data extracted from each MA included the summary estimate of the effect of ginger, the formulation of the ginger treatment, gestational timepoint at intervention, population enrolled in the study, type of intervention, comparator intervention, and number of study participants. The evidence scan identified 90 articles relevant to ginger use during pregnancy and lactation. Seven MAs of ginger use for treating nausea and vomiting of pregnancy reported 22 independent studies with a 49% study overlap overall. The majority of the MAs found a significant positive effect of ginger on the improvement of nausea in pregnancy compared with placebo, or equivalence to conventional treatments, and no evidence of significant adverse effects. The quality of the MAs ranged from critically low to low. The evidence suggests that ginger is effective at reducing nausea in pregnancy; however, the included studies contained substantial heterogeneity and were of low quality.