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Updated: Apr 4, 2026
Author Spotlight: Studying the Impact of Maternal Dietary Deficiencies on Long-Term Offspring Health Outcomes
Published on: June 28, 2024
The effect of zinc supplementation on pregnancy outcome: a randomized controlled trial
Ziba Zahiri Sorouri1, Hossein Sadeghi2, Davoud Pourmarzi2
1a Department of Obstetrics and Gynecology , Reproductive Health Research Center, Alzahra Hospital, Guilan University of Medical Sciences , Rasht , Iran and.
Objectives:
This study aimed to evaluate the impact of prenatal zinc supplementation on pregnancy outcomes.
Methods:
A randomized controlled trial with equal randomization (1:1) was conducted on 540 pregnant women in Rasht, Iran from January 2010 to January 2012. Participants were randomly assigned to receive a daily supplement including 400-µg folic acid and 30-mg ferrous sulfate, with or without 15-mg zinc sulfate from the 16th week of gestation until delivery.
Results:
Mean difference of birth weight between the two groups was not significantly different (3262 ± 390 g in the zinc, 3272 ± 403 g in the no-zinc groups) (p = 0.780). There were no significant differences between the two groups in terms of means of head circumference (p = 0.999), length (p = 0.848), and gestational age at birth (p = 0.057) incidences of low birth weight (p = 0.863), macrosomia (p = 0.642), and the Apgar score >7 at 5 min (p = 0.999), incidences of preterm delivery (p = 0.999), pre-eclampsia (p = 0.835), premature rupture of membranes (p = 0.630), and spontaneous abortion (p = 0.772). Abruption of placenta, amnionitis, stillbirth, and intrauterine death were not observed.
Conclusion:
Based on our findings, 15-mg zinc supplementation daily from 16 weeks of pregnancy until delivery cannot improve pregnancy outcomes.
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