Effects of zinc supplementation during pregnancy on neonatal health:a meta-analysis of randomized controlled trials

Objective To comprehensively summarize the associations between zinc supplementation and birth weight,birth length,birth head circumference,preterm birth,low birth weight,and death in the perinatal period of neonates and to provide evidences for zinc supplementation in pregnant women.Methods We searched PubMed,EMBASE,OVID,SCOPUS,Web of Science,Sino Med(CBM)and Wanfang database and collected data about birth weight,birth length,birth head circumference,preterm birth,low birth weight and death in the perinatal period from the included studies.The data were analyzed with Review Manager 5.2.Results Fifteen randomized controlled trial studies with sufficient information were included.The combined mean difference(MD)(95% confidence interval95% CI)of zinc supplementation was 18.13(-26.72-62.99)for birth weight,-0.10(-0.24-0.03)for birth length,-0.04(-0.13-0.05)for birth head circumference.The combined risk ratio(RR)(95% CI)was 0.84(0.74-0.96)for preterm birth,0.85(0.66-1.11)for low birth weight,1.27(0.68-2.38)for death in the perinatal period of neonates.The combined MD(95% CI)of only zinc supplementation was -30.73(-86.82-25.35)for birth weight.The combined RR(95% CI)of only zinc supplementation was 0.89(0.71-1.11)for preterm birth,0.77(0.44-1.37)for low birth weight.Similarly,the combined MD(95% CI)of multiple micronutrients supplementation with zinc was 38.13(-20.60-96.85)for birth weight,-0.08(-0.24-0.08)for birth length,-0.02(-0.18-0.13)for birth head circumference.The combined RR(95% CI)was 0.78(0.64-0.95)for preterm birth,0.80(0.51-1.26)for low birth weight.Conclusion The results of this analysis indicate that zinc supplementation could reduce preterm birth and has significant effects on birth weight,birth length,head circumference,low birth weight and death of neonates in the perinatal period.