Related Experiment Video
Updated: Jun 6, 2026
Quantitating Iron Transport Across the Mouse Placenta In Vivo Using Nonradioactive Iron Isotopes
Published on: May 10, 2022
Maternal iron status during pregnancy: relationship with fetal growth; ECLIPSES study
Sandra Díaz-Torres1,2, Andrés Díaz-López3, Cristina Jardí3
1Centre d'atenció a la salut sexual i reproductiva, (ASSIR) Reus, Tarragona, Spain.
Background:
Maternal iron deficiency anemia has been linked to reduced fetal growth assessed at birth, but research on elevated maternal iron levels and their impact on fetal growth during pregnancy is limited. In this study, we analysed the association between maternal serum ferritin (SF) levels without anemia during pregnancy and fetal growth in each trimester up until birth.
Methods:
We prospectively analysed data from 713 mother-child pairs from the ECLIPSES cohort. Maternal SF was measured in the 1st and 3rd trimester (T) of pregnancy. SF trajectories were calculated considering the SF tertiles (low, medium, high) from T1 to T3: low FS, medium SF (reference), and high SF trajectories. Fetal biometry during gestation (estimated fetal weight (EFW), femur length, head circumference (HC); and anthropometric measurements at birth (weight, length and HC) were estimated.
Results:
In the fetus, increased maternal SF levels without anemia at T1 and/or T3 were associated with lower fetal biometrics (EFW, femur length, HC) at T3. The high SF levels in both, tertiles and trajectories, were associated with lower femur length. Further, high SF levels were positively associated with greater risk of low (< 10th percentile) EFW (OR: 1.58; 95%IC, 1.14-2.18) and low femur length (when SF was modeled as either continuous, tertile, or trajectory exposure), with a doubling of the risk of low femur with high FS trajectory (OR: 4.26; 95%IC, 1.84-9.83). Conversely, low SF tertiles, without anemia, at both T1 (β:34.80, p = 0.024) and T3 (β:38.42, p = 0.040) were associated with a higher EFW. In newborns, high maternal SF levels without anemia, but not low levels, was negatively associated with birth weight and HC. A high SF trajectory doubled this negative effect on birth weight (β:-107.96, p = 0.011). The risk of having a low birth weight (< 2.500 g) was consistent with high SF levels at both T1 and T3, and was markedly tripled in the high FS trajectory (OR: 13.56; 95%IC, 2.27-81.17).
Conclusions:
Our findings suggest that high levels of maternal SF during pregnancy are associated with reduced fetal growth until birth, whereas low levels without anemia do not appear to be detrimental.
Trial Registration:
This clinical trial is registered at www.clinicaltrialsregister.eu as EudraCT number 2012-005480-28. Registration date: April 04, 2013.
