Evidence from a systematic review on antenatal zinc supplementation was evaluated as part of the World Health Organization (WHO) antenatal care (ANC) guideline development process in 2016, and the following recommendation on zinc supplementation was made: “Zinc supplementation for pregnant women is only recommended in the context of rigorous research.” The Guideline Development Group (GDG) made this recommendation because it felt that the evidence on the intervention was incomplete and that more research was necessary. Since the publication of the systematic review, four additional randomized controlled trials have been published; therefore, in April 2019, the Executive Guideline Steering Group (GSG) prioritized the WHO recommendation on antenatal zinc supplementation for updating. Zinc is a trace element found in many foods, particularly in meat, but also in dairy products, legumes and unrefined cereals. It plays an important role in many biological processes that contribute to human growth and development, and also to immunity. As it is not stored in the body, it needs to be consumed regularly to prevent zinc deficiency, which is particularly common in low- and middle-income countries, where dietary intake of zincrich foods is often low. However, the effects of zinc deficiency in pregnancy have not been clearly established. In January 2021, a WHO-convened GDG comprising most of the 2016 GDG members re-evaluated the evidence on antenatal zinc supplementation, updating the recommendation on zinc in accordance with WHO’s living guidelines approach.