Study sample
IRON EXCESS, EARLY PREGNANCY
The ECLIPSES study was a population‐based randomized controlled trial conducted in 2013–2017 in Tarragona, Spain, which aimed to evaluate the effectiveness of different doses of prenatal iron supplementation on maternal iron status at the end of pregnancy in nonanaemic women in early pregnancy (Vázquez et al., Participating women were recruited before the gestational week (GW) 12 and allocated into two groups according to their Hb levels at the time. Women in Stratum 1 (initial Hb = 110–130 g/L) were randomly prescribed a daily dose of 40 or 80 mg of iron aiming to prevent an iron deficit, whereas those in Stratum 2 (initial Hb > 130 g/L) received 40 or 20 mg of iron daily aiming to prevent the risk of developing iron excess (Figure Flowchart of the study. GW, gestational week; Hb, haemoglobin.