Treatment of Nausea and Vomiting With Zingiber officinale in Pregnancy: An Umbrella Review of Systematic Reviews With Meta-Synthesis.

Abstract

Affecting approximately 85% of expectant mothers during the first trimester, nausea and vomiting of pregnancy (NVP) are frequently reported symptoms. Despite numerous existing systematic reviews and meta-analyses (SRMs), findings remain inconsistent. Consequently, this study assesses the quality of these prior SRMs and investigates the efficacy of ginger as a treatment for NVP. A comprehensive search was conducted across PubMed, Scopus, Cochrane, and Web of Science from their inception through December 30, 2024. This review includes peer-reviewed English-language SRMs investigating ginger as a therapeutic intervention for pregnancy-related nausea and vomiting. Methodological rigor was evaluated using the AMSTAR-2 checklist, while evidence quality was assessed via the GRADE approach. Findings are synthesized narratively through content analysis. The study protocol was prospectively registered in the PROSPERO database. This study analyzed 18 systematic reviews, of which eight (44%) incorporated meta-analyses. The Rhodes Index of Nausea and Vomiting (RINV) emerged as the primary tool for evaluating outcomes. Regarding study reporting and transparency, seven studies registered their protocols in PROSPERO, while eight adhered to the PRISMA checklist. Overall, the included reviews demonstrated low methodological quality, with a mean score of 11.77. Specifically, 28% (n = 5) were rated as high quality, 28% (n = 5) as moderate, 22% (n = 4) as low, and 22% (n = 4) as critically low. Taking ginger supplements (usually between 450 and 1950 mg daily) significantly decreases the severity and occurrence of nausea and vomiting compared to a placebo. This benefit is more noticeable for nausea than for vomiting, where the results are less consistent. Numerous studies have shown that ginger does not raise the risk of adverse effects, such as spontaneous abortion or side effects like heartburn and drowsiness, when compared to a placebo or vitamin B6. Current evidence clearly shows that ginger is a safe and effective treatment for nausea and vomiting during pregnancy, with effectiveness similar to vitamin B6 and some traditional medications, and it has a good safety profile. Ginger can be recommended as a dependable medicinal herb for women dealing with NVP, though more research is needed to determine the best doses and confirm long-term safety.