Preliminary Study of Iron Concentration in the Human Placenta in Twin Pregnancies

Abstract

Background: Pregnancy significantly increases the demand for iron (Fe) in the female body to facilitate maternal blood volume expansion, placental development, and fetal growth. As Fe flux in pregnancy is significantly influenced by the placenta, the aim of this study was to determine the dependencies between the Fe concentration in the placenta, the infant’s morphometric parameters and the woman’s morphological blood parameters in the last trimester. Methods: The study was conducted on 33 women with multiple (dichorionic–diamniotic) pregnancies from whom the placentas were drawn, and their 66 infants, including pairs of monozygotic (n = 23) and mixed-sex twins (n = 10). Fe concentrations were determined based on inductively coupled plasma atomic emission spectroscopy (ICP-OES) using ICAP 7400 Duo, Thermo Scientific. Results: The results of the analysis showed that lower placental Fe concentrations were associated with deteriorated morphometric parameters of infants, including weight and head circumference. Although we found no statistically significant dependencies between Fe concentration in the placenta and the women’s morphological blood parameters, higher Fe concentration in the placenta of mothers supplemented with Fe correlated with better morphometric parameters in infants compared to those whose mothers received no Fe supplementation. Conclusions: The research adds additional knowledge for placental iron-related processes during multiple pregnancies. However, many limitations of the study do not allow detailed conclusions to be assessed, and statistical data should be assessed conservatively.

Associations of maternal serum concentration of iron-related indicators with birth outcomes in Chinese: a pilot prospective cohort study

“…Our findings were supported by several studies that found no significant associations between iron exposure and body length/height [25,41] or head circumference [22,23,25]. However, other studies have found positive [7,8,19] or negative [29][30][31] associations between iron exposure and these two anthropometric indicators. Sources of heterogeneity in these studies may include different routes of iron exposure (including diet, iron supplementation, blood, and placenta), different study populations (in some studies, outcomes were measured in children rather than fetal or neonatal), and differences in baseline iron levels in the developed and developing countries studied, such as Sweden and Honduras [29].…”

“…These results were further supported by several other studies investigating iron exposure from dietary intake [24], blood [25], and amniotic fluid [26]. Conversely, several studies have suggested potential adverse associations between higher blood or placental iron status and anthropometric indicators [27][28][29][30][31]. Two studies of South Korean women found that higher serum ferritin concentration or dietary iron intake were associated with lower femur length and biparietal diameter [27,28].…”

“…Two studies of South Korean women found that higher serum ferritin concentration or dietary iron intake were associated with lower femur length and biparietal diameter [27,28]. Similar negative associations were observed in children between higher iron status (or higher hemoglobin levels) and head circumference [29], birth weight [30,32,33], and height [31].…”