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.
Nausea and vomiting are common in early pregnancy.1 Although the condition is not life threatening, it can cause considerable distress to pregnant women and their families. Moreover, it can cause temporary disability in a high proportion of employed women, and as many as 25% of nauseous pregnant women require time off from work.2 The cause of nausea and vomiting in pregnancy is still unknown. As a consequence, a wide variety of treatments have been used empirically.1,3 However, the use of drugs for this condition is limited because of the concern for potential teratogenic effects.1 Natural products such as ginger, red raspberry, and wild yam have been suggested as alternative treatments, but data on their efficacy are limited.1
In one study, ginger was found to be superior to dimenhydrinate in reducing motion sickness.4 In another study, ginger was found to significantly reduce postoperative emetic sequelae.5 Only one trial of ginger in nausea of pregnancy was identified by an online search of the National Library of Medicine's MEDLINE database from 1990 to 2000, using the search terms “nausea and vomiting and ginger” and “hyperemesis gravidarum and ginger.” Cochrane Database of Systematic Reviews on CD-ROM (Issue 1, 2000) also was searched but no additional trials were identified. In addition, citations and bibliographies of all retrieved papers were reviewed to find any trial not found in the automated search.
The only study reported so far was a randomized, double-blind, cross-over trial of ginger in hospitalized patients with hyperemesis gravidarum.6 The purpose of the present study was to further evaluate the effectiveness of ginger in a randomized, double-masked, parallel design, involving a larger group of subjects with less severe manifestation of nausea and vomiting.
Ginger is effective for treating nausea and vomiting in pregnancy.
Department of Obstetrics and Gynecology, Chiang Mai University, Chiang Mai, Thailand.
Address reprint requests to: Teraporn Vutyavanich, MD, MSc, Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand. E-mail: firstname.lastname@example.org
Received August 25, 2000. Received in revised form November 29, 2000. Accepted December 15, 2000.