Results
We initially identified 135 records using the MeSH keywords of early pregnancy, ginger, nausea, and vomiting. After removing duplicates and further screening, 8 full articles were retrieved. Two of them were excluded because of irrelevance. Consensus was reached among the reviewers to include the final 6 studies. The 2009 PRISMA checklist was used; the PRISMA flow diagram is given in the Appendix.