Interventions for Nausea and Vomiting in Early Pregnancy

A Cochrane review [Abstract] 1 included 41 trials involving a total of 5 449 women. Ginger, vitamin B6, and several antiemetic drugs were studied. There was a trend favouring ginger compared to placebo, but the results were nonsignificant and not consistent. There was no difference in nausea in studies comparing ginger with vitamin B6. In 2 trials comparing vitamin B6 with placebo the reduction in nausea score was nonsignificant (RR 0.92, 95% CI 0.40 to 1.44; n=393 ). The evidence about anti-emetic drugs was very limited. Information on maternal and fetal adverse outcomes was sparce.

Another Cochrane review [Abstract] 2 included 25 trials involving a total of 2 052 women, but the majority of 18 different comparisons included data from single studies with small numbers of participants. In a study with 92 participants, women taking vitamin B6 had a slightly longer hospital stay compared with placebo (mean difference (MD) 0.80 days, 95% CI 0.08 to 1.52). There was insufficient evidence to demonstrate a difference in other outcomes including mean number of episodes of emesis (MD 0.50, 95% CI -0.40 to 1.40) or side effects.

A systematic review 3 included 78 studies (n=8930). Evidence of 35 RCTs with low risk of bias showed that ginger, vitamin B6, antihistamines, metoclopramide (for mild symptoms), pyridoxine-doxylamine, and ondansetron (for moderate symptoms) were associated with improved symptoms compared with placebo.

A multicenter, randomized, double-blind, placebo-controlled trial 4 in China included 352 women with moderate to severe nausea and vomiting. Participants receiving acupuncture 30 minutes per day (mean difference [MD] -0.7, 95% CI -1.3 to -0.1), doxylamine-pyridoxine (MD -1.0, 95% CI -1.6 to -0.4), and the combination of both (MD -1.6, 95% CI -2.2 to -0.9) for 14 days had a larger reduction in PUQE score than their respective control groups (sham acupuncture, placebo, and sham acupuncture plus placebo).

Comment: The quality of evidence is downgraded by shortcomings in study quality and by inconsistency.

References

• Matthews A, Haas DM, O'Mathúna DP et al. Interventions for nausea and vomiting in early pregnancy. Cochrane Database Syst Rev 2015;(9):CD007575. [PubMed]
• Boelig RC, Barton SJ, Saccone G et al. Interventions for treating hyperemesis gravidarum. Cochrane Database Syst Rev 2016;(5):CD010607. [PubMed]
• McParlin C, O'Donnell A, Robson SC et al. Treatments for Hyperemesis Gravidarum and Nausea and Vomiting in Pregnancy: A Systematic Review. JAMA 2016;316(13):1392-1401. [PubMed]
• Wu XK, Gao JS, Ma HL, et al. Acupuncture and Doxylamine-Pyridoxine for Nausea and Vomiting in Pregnancy : A Randomized, Controlled, 2 × 2 Factorial Trial. Ann Intern Med 2023;176(7):922-933 [PubMed]