Ginger for nausea and vomiting in pregnancy: randomized, double-masked, placebo-controlled trial.

OBJECTIVE To determine the effectiveness of ginger for the treatment of nausea and vomiting of pregnancy. METHODS Women with nausea and vomiting of pregnancy, who first attended an antenatal clinic at or before 17 weeks' gestation, were invited to participate in the study. During a 5-month period, 70 eligible women gave consent and were randomized in a double-masked design to receive either oral ginger 1 g per day or an identical placebo for 4 days. Subjects graded the severity of their nausea using visual analog scales and recorded the number of vomiting episodes in the previous 24 hours before treatment, and again during 4 consecutive days while taking treatment. At a follow-up visit 7 days later, five-item Likert scales were used to assess the severity of their symptoms. RESULTS All participants except three in the placebo group remained in the study. The visual analog scores of posttherapy minus baseline nausea decreased significantly in the ginger group (2.1 +/- 1.9) compared with the placebo group (0.9 +/- 2.2, P =.014). The number of vomiting episodes also decreased significantly in the ginger group (1.4 +/- 1.3) compared with the placebo group (0.3 +/- 1.1, P <.001). Likert scales showed that 28 of 32 in the ginger group had improvement in nausea symptoms compared with 10 of 35 in the placebo group (P <.001). No adverse effect of ginger on pregnancy outcome was detected. CONCLUSION Ginger is effective for relieving the severity of nausea and vomiting of pregnancy.