The effects of pyridoxine (vitamin B6) supplementation in nausea and vomiting during pregnancy: a systematic review and meta-analysis

Purpose Nausea and vomiting during pregnancy (NVP) are common symptoms in pregnancy. Although no definitive treatment option for NVP, pyridoxine (Vitamin B6) supplementation has been used widely. The present study aims to systematically evaluate the current evidence regarding pyridoxine for the treatment of NVP. Methods Data were obtained using a stepwise search process using keywords in the following online medical databases; PubMed((R)), Web of Science((R)), and Scopus((R)) for studies published before 1st May 2021. Studies reporting intervention with pyridoxine supplementation alone and/or with other active substances were included. A meta-analysis was performed on the PUQE score and Rhode's score for nausea and vomiting. Findings Initial database searching indicated 548 potentially eligible articles, of which 18 studies satisfying the inclusion criteria were selected. Eight studies showed beneficial effects with pyridoxine alone as the supplementation, while six others found that the supplementation of pyridoxine in combination with another active substance had favourable effects. Supplementation of pyridoxine alone as well as combined treatment of pyridoxine with an active ingredient as the intervention significantly improved the symptoms of nausea according to Rhode's score [0.78 [95% CI: 0.26, 1.31; p = 0.003; I2 = 57%, p = 0.10)] and PUQE score [0.75 (95% CI: 0.28, 1.22; p = 0.002; I2 = 0%, p = 0.51)], respectively. Conclusion Supplementation of pyridoxine alone as well as with an active ingredient demonstrated beneficial effects for women suffering from NVP.