Search Strategy
A literature search of published medical reports was performed in all languages using PubMed, EMBASE, CINAHL, the Cochrane Library, and all evidence-based medicine reviews using the OVID Portal of Queen's University, Kingston, Ontario. Abstracts were initially obtained using MeSH keywords ofearly pregnancy,nausea, vomiting, and ginger. Manual searches of references and review articles supplemented the computerized search.