Relationship of maternal and newborn (cord) serum ferritin concentrations measured by immunoradiometry

Serum ferritin concentration was determined by immunoradiometry in venous blood samples of 45 pregnant women at term, in their babies' cord blood samples, and blood specimens obtained from 43 infants aged 3-12 months. The concentration of ferritin was higher in cord serum than in respective maternal samples and infant specimens. Low values were found in more than half of the maternal venous samples. Iron stores of newborns delivered by mothers with low serum ferritin concentration were lower than in newborns of mothers having normal ferritin levels. Serum ferritin measurement is a sensitive method to determine iron deficiency in pregnancy.     

Changes in the concentration of ferritin in the serum during fetal life in singletons and twins

Concentration of serum ferritin was analyzed in cord blood samples of 34 preterm and 24 full-term subjects, 10 fetuses which were aborted by laparotomy at 14-20 weeks of gestation, and 20 pairs of twins. The findings indicated that the fetal amount of storage iron gradually increases as the gestational age increases, it is similar in singletons and twins, within the pairs of twins, and slightly lower in some small-for-dates newborns. There was no correlation between fetal ferritin and maternal iron status. Our data suggest that the accumulation of fetal iron stores is not regulated by the fetus itself, or by maternal iron metabolism. Thus, we speculate that the placenta may have a role in this regulation.     

PLASMA FERRITIN CONCENTRATIONS IN PRETERM INFANTS IN CORD BLOOD AND DURING THE EARLY ANAEMIA OF PREMATURITY

Abstract. Hågå, P. (Department of Paediatrics and Paediatric Research Institute, National Hospital of Norway, and Department of Paediatrics, Oslo City Hospital, Ullevål, Oslo, Norway). Plasma ferritin concentrations in preterm infants in cord blood and during the early anaemia of prematurity. Acta Paediatr Scand, 69: 637, 1980.—Ferritin concentrations in cord blood were determined in 22 normal term and 32 preterm infants (birth weights 600–2000 g). Eight of the preterms were SGA infants. AGA preterm infants had significantly lower concentrations than term infants, and the SGA preterm newborn had even lower levels. Plasma ferritin in cord blood of the term and AGA preterm infants correlated positively with plasma iron and transferrin saturations, but not with the transferrin level, while plasma iron and transferrin concentrations correlated positively. In a longitudinal study, 17 AGA preterm infants (birth wights 850–1500 g) were followed during the early anaemia of prematurity. Iron was supplemented from 4 weeks of age. Plasma ferritin rose rapidly during the first days after birth, peak levels being reached at 1–4 weeks. Thereafter linear falls (semilog) occurred with similar slopes in different infants. Transferrin concentrations showed a slow progressive increase from 0–8 weeks. Plasma ferritin, after reaching the peak value, correlated negatively with weight gain. No infant had low ferritin values indicating iron deficiency during the early anaemia.     

Relationship between newborn and maternal iron status and haematological indices.

The haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin, haematocrit, serum iron and total iron binding capacity, and serum ferritin concentrations in umbilical cord blood samples taken from 96 appropriate-for-gestational age infants delivered at term were measured and compared to the respective maternal values measured at 36 weeks' gestation. All the values were higher in cord blood. Only maternal mean corpuscular volume and mean corpuscular haemoglobin were correlated with cord serum iron. Cord blood haematological indices were not correlated with either gestation at delivery or birth weight. However, newborn serum ferritin was positively correlated with gestation at delivery, while the maternal:newborn ferritin ratio was inversely correlated with gestation and birth weight. The results suggest that maternal haematological and iron indices are not predictive of the haemoglobin or iron status of the newborn, and that the fetus continues to take up iron from the mother until delivery.     

Cord blood transferrin receptors to assess fetal iron status.

OBJECTIVE: To study iron status at different gestational ages using cord blood serum transferrin receptors (STfRs). METHODS: STfRs, iron, ferritin, total iron binding capacity, haemoglobin, and reticulocytes were measured in 144 cord blood samples. The babies were divided into three groups according to gestation (26 very preterm (24-29 weeks); 50 preterm (30-36 weeks); 68 term (37-41 weeks)). RESULTS: Serum iron, ferritin, and total iron binding capacity were highest at term, whereas reticulocytes were highest in the very preterm. STfR levels were not influenced by gestation. Haemoglobin (r = 0.46; p < 0.0001) and reticulocytes (r = 0.42; p < 0.0001) were the only indices that independently correlated with STfR levels. CONCLUSIONS: STfR levels in cord blood are not directly influenced by gestation and probably reflect the iron requirements of the fetus for erythropoiesis.     

Fetal iron status in maternal anemia

Hemoglobin, serum iron, transferrin saturation and ferritin were measured on paired maternal and cord blood samples in 54 anemic (hemoglobin < 110 g/L) and 22 non-anemic (hemoglobin ≥ 110 g/L) pregnant women at term gestation. The levels of hemoglobin, serum iron, transferrin saturation and ferritin were significantly low in the cord blood of anemic women, suggesting that iron supply to the fetus was reduced in maternal anemia. The linear relationships of these parameters with both maternal hemoglobin and maternal serum ferritin indicated that the fetus extracted iron in amounts proportional to the levels available in the mother. Infants of mothers with moderate and severe anemia had significantly lower cord serum ferritin levels and hence poor iron stores at birth. It is concluded that iron deficiency anemia during pregnancy adversely affects the iron endowment of the infant at birth.     

Cord transferrin and ferritin values in newborn infants at risk for prenatal uteroplacental insufficiency and chronic hypoxia

We measured cord transferrin and ferritin levels in 50 newborn infants with fetal conditions associated with either uteroplacental vascular insufficiency or chronic hypoxia. Sixteen small for gestational age infants, 21 infants of mothers with preeclampsia, and 13 symptomatic infants of diabetic mothers had significantly higher transferrin levels and lower ferritin levels and calculated iron stores than did asymptomatic gestational age-matched control infants without these conditions. Cord ferritin levels and calculated iron stores were significantly lower in the infants of diabetic mothers than in any other group of infants. Cord transferrin levels were inversely correlated with ferritin levels (r = -0.59, P less than 0.001) and were unrelated to transthyretin levels and birth weight in the high-risk infants, but were positively correlated with ferritin levels (r = 0.50, P less than 0.001), transthyretin levels (r = 0.65, P less than 0.001), and birth weight (r = 0.75, P less than 0.001) in the control infants. We conclude that cord transferrin levels do not reflect protein-energy status in newborn infants with prenatal histories suggesting uteroplacental insufficiency or chronic hypoxia, and that when associated with decreased cord ferritin levels, indicate possible impaired iron stores in these infants.     

Storage iron in human foetal organs

Maternal plasma iron and storage iron (non-heme) in the foetal liver were estimated in 108 foetuses whose gestational ages ranged from 12-44 weeks. Simultaneous estimations of storage iron were also made on the spleen and kidney in 70 and 69 of these foetuses respectively. Although the concentration of iron per g wet tissue in these organs remained practically the same at all gestations, the total storage iron content increased with the increase in gestation due to growth of these organs. The liver, in particular, showed a steep rise in total iron content in the last 8 weeks of gestation. There was a significant positive correlation between the total storage iron content in the foetal organs and the birth weight and gestational age of the foetus, suggesting that the preterm infants had smaller iron stores at birth as compared to infants born at term. The direct relation of the concentration as well as the total content of storage iron in the foetal liver with the maternal plasma iron levels suggested that babies born to iron deficient mothers had poor iron stores in their livers.     

Iron status of the preterm infant during the first year of life

The iron status of 49 preterm infants (mean gestational age 33.1 weeks) was assessed serially during the 1st year of life. Haemoglobin concentration, serum ferritin, serum transferrin, serum iron, and transferrin saturation were measured on nine occasions in each infant. In 16 infants of gestational age 28-32 weeks the haemoglobin concentration was significantly lower at 3, 6, and 9 weeks when compared to 33 infants of gestational age 33-36 weeks. For all other measures of iron status there were no significant differences between these gestational age groups. For the entire group of 49 infants the mean haemoglobin concentration reached a nadir of 11.2 g/dl at 9 weeks. Mean serum iron and transferrin saturation reached peaks of 24 mumol/l and 65%, respectively, at 3 weeks. The mean serum ferritin remained over 100 micrograms/l until after 18 weeks. 13 infants (26%) had iron deficiency defined as either serum ferritin less than 10 micrograms/1 (n = 10) or transferrin saturation less than 10% (n = 5) or both (n = 3).     

Storage Iron in Human Foetal Organs

ABSTRACT. Maternal plasma iron and storage iron (non-heme) in the foetal liver were estimated in 108 foetuses whose gestational ages ranged from 12–44 weeks. Simultaneous estimations of storage iron were also made on the spleen and kidney in 70 and 69 of these foetuses respectively. Although the concentration of iron per g wet tissue in these organs remained practically the same at all gestations, the total storage iron content increased with the increase in gestation due to growth of these organs. The liver, in particular, showed a steep rise in total iron content in the last 8 weeks of gestation. There was a significant positive correlation between the total storage iron content in the foetal organs and the birth weight and gestational age of the foetus, suggesting that the preterm infants had smaller iron stores at birth as compared to infants born at term. The direct relation of the concentration as well as the total content of storage iron in the foetal liver with the maternal plasma iron levels suggested that babies born to iron deficient mothers had poor iron stores in their livers.     

Serum concentrations of thyroxine-binding globulin, prealbumin and albumin in healthy fullterm, small-for-gestational age and preterm newborn infants.

Simultaneous serum concentrations of thyroxine-binding globulin (TBG), prealbumin (TBPA) and albumin (Alb) were measured in 130 fullterm, 32 small-for-gestational age and 25 preterm infants during their first six days of life. In all infants serum concentrations of TBG were higher and serum TBPA and Alb were lower than in male adults. Even higher serum TBG levels were found in the mothers. There was no correlation between serum concentrations in paired maternal and cord sera. In infants with birth weights appropriate for gestation serum TBG, TBPA, and Alb concentrations increased progressively with gestational age. In small-for-gestational age infants born at term serum concentrations of TBG and Alb were lower than those in fullterm, but higher than those in premature newborns. Serum TBPA in small-for-gestational age babies was even lower than seen in prematures. A positive correlation was found between thyroid hormones and TBG concentrations, not between serum TBPA and thyroid hormones. The ratios between serum concentration of thyroid hormones and proteins might indicate that more thyroid hormonebinding sites are occupied in fullterm than in low birth-weight newborns. However, the main reason for the different serum levels of thyroid hormones in fullterm, small-for-gestational age and preterm babies is probably the various serum TBG concentrations demonstrated in these infants.     

早产儿和足月儿脐血及母亲静脉血硒含量的比较

目的：硒是一种人体必需的微量元素,在细胞抗氧化防御系统中发挥着主要的作用。在早期早产儿中,低水平的硒会增加诸如慢性新生儿肺疾病、早产儿视网膜病等并发症的发生。该研究旨在检测并比较早产儿和足月儿脐血及母亲静脉血硒含量。方法：选取2008年3~7月间30个足月儿（胎龄>37 周）和30个早产儿（胎龄< 34 周）及他们的母亲作为研究对象。用原子吸收光谱法测定脐血和母亲静脉血的硒含量。结果：足月儿的脐血硒平均含量高于早产儿,差异有非常显著性(124.80± 13.72 μg/L vs 100.30 ± 11.72 μg/L, P=0.0001) 。 足月儿母亲与早产儿母亲的的平均硒含量差异无显著性 (117.03±17.15 μg/L vs 110.56±17.49 μg/L, P=0.15)。将所有婴儿的资料一起分析时,发现脐血硒含量与胎龄和出生体重显著正相关(r=0.66, P<0.0001;r=0.59, P<0.0001)。60例婴儿母亲中,无一例的血硒含量低于正常参考值的下限（70.0 μg/L）。将所有婴儿及其母亲的资料一起分析时,发现母亲血硒含量与其婴儿脐血硒含量呈显著正相关 (r=0.40, P<0.001)。结论：在伊斯法罕地区,孕母的血硒水平处于一个良好的状态,血硒水平不是早产的预测指标。足月儿的脐血硒含量高于早产儿,但足月儿和早产儿的脐血硒含量均在正常参考范围。［中国当代儿科杂志,2009,11（7）：513-516］     

CORD BLOOD HAEMOGLOBIN, IRON AND FERRITIN STATUS IN MATERNAL ANAEMIA

ABSTRACT. Maternal and cord blood haemoglobin, serum iron, transferrin saturation and ferritin were studied in sets of 30 anaemic (haemoglobin <110 g/l) and 21 nonanaemic (haemoglobin ≧110 g/l) mothers. The cord serum iron, transferrin saturation and ferritin concentrations had significant correlation with maternal haemoglobin. The significant low levels of these parameters suggested that maternal anaemia adversely affected the iron status including iron stores of the newborns. The cord serum iron of 15.2±4.35 μmol/l and ferritin of 29.7±10.93 ng/ml seem to be effective to maintain cord haemoglobin levels. Thus, anaemic mothers with reasonably maintained ferritin and trasferrin saturation levels provide sufficient iron for maintenance of cord haemoglobin, although foetal iron stores are likely to be depleted.     

Lack of correlation between free erythrocyte porphyrin and serum ferritin values at birth and at 2 months of life in low birthweight infants

Red cell free erythrocyte porphyrin and serum ferritin determinations were performed on capillary blood specimens from 63 healthy infants weighing 2500 g or less at birth, during the first week of life, and, from 44 of them, again at 8-10 weeks. Free erythrocyte porphyrin values were high both at 3-7 days (mean 156 microgram/100 ml RBC) and at 8-10 weeks (mean 128 microgram/100 ml RBC). The respective serum ferritin values were also high (mean 226 and 107 ng/ml), excluding a depletion in iron stores. In addition, no correlation was found between free erythrocyte porphyrin and serum ferritin values either at birth or at age 2 months. These findings are consistent with an earlier hypothesis that in the presence of iron stores, the rate of iron release from the stores in low birthweight infants may not be sufficient to maintain optimal erythropoiesis if the demand is accelerated.     

Lack of correlation between free erythrocyte porphyrin and serum ferritin values at birth and at 2 months of life in low birthweight infants.

Red cell free erythrocyte porphyrin and serum ferritin determinations were performed on capillary blood specimens from 63 healthy infants weighing 2500 g or less at birth, during the first week of life, and, from 44 of them, again at 8-10 weeks. Free erythrocyte porphyrin values were high both at 3-7 days (mean 156 microgram/100 ml RBC) and at 8-10 weeks (mean 128 microgram/100 ml RBC). The respective serum ferritin values were also high (mean 226 and 107 ng/ml), excluding a depletion in iron stores. In addition, no correlation was found between free erythrocyte porphyrin and serum ferritin values either at birth or at age 2 months. These findings are consistent with an earlier hypothesis that in the presence of iron stores, the rate of iron release from the stores in low birthweight infants may not be sufficient to maintain optimal erythropoiesis if the demand is accelerated.     

SERUM CONCENTRATIONS OF THYROXINE-BINDING GLOBULIN, PREALBUMIN AND ALBUMIN IN HEALTHY FULLTERM, SMALL-FOR-GESTATIONAL AGE AND PRETERM NEWBORN INFANTS

Abstract. Jacobsen, B. B., Peitersen, B., Andersen, H. J. and Hummer, L. (The University Clinic of Paediatrics, Children's Hospital Fuglebakken and the Departments of Nuclear Medicine, Rigshospitalet, Copenhagen, Denmark). Serum concentrations of thyroxine-binding globulin, prealbumin and albumin in healthy fullterm, small-for-gestational age and preterm newborn infants. Acta Paediatr Scand, 68: 49, 1979.—Simultaneous serum concentrations of thyroxine-binding globulin (TBG), prealbumin (TBPA) and albumin (Alb) were measured in 130 fullterm, 32 small-for-gestational age and 25 preterm infants during their first six days of life. In all infants serum concentrations of TBG were higher and serum TBPA and Alb were lower than in male adults. Even higher serum TBG levels wer found in the mothers. There was no correlation between serum concentrations in paired maternal and cord sera. In infants with birth weights appropriate for gestation serum TBG, TBPA, and Alb concentrations increased progressively with gestational age. In small-for-gestational age infants born at term serum concentrations of TBG and Alb were lower than those in full-term, but higher than those in premature newborns. Serum TBPA in small-for-gestational age babies was evne lower than seen in prematures. A positive correlation was found between thyroid hormones and TBG concentrations, not between serum TBPA and thyroid hormones. The ratios between serum concentration of thyroid hormones and proteins might indicate that more thyroid hormonebinding sites are occupied in fullterm than in low birth-weight newborns. However, the main reason for the different serum levels of thyroid hormones in fullterm, small-for-gestational age and preterm babies is probably the various serum TBG concentrations demonstrated in these infants.     

Serum ferritin, iron levels and iron binding capacity in asymmetric SGA babies.

The concentration of serum ferritin reflects the extent of iron stores in premature infants. We aimed to determine serum ferritin levels and iron status in asymmetric small for gestational age (SGA) babies. This study was performed on 21 SGA babies and 19 appropriate for gestational age (AGA) babies. Hemoglobin, iron, iron binding capacity and ferritin levels were investigated in the first six hours after the birth. Hemoglobin levels in the SGA and control groups were 20.9 +/- 1.3 (19.4-23.4 g/dl) and 19.6 +/- 0.8 (18.5-21.5 g/dl), respectively (p = 0.001). Serum ferritin levels in the SGA and AGA groups were 58.36 +/- 20.1 ng/ml and 90.46 +/- 30.5 ng/ml, respectively. Ferritin levels were found lower in the SGA group (p < 0.001). In the SGA group, decreased serum iron and increased iron binding capacity were found but the difference was not significant (p > 0.05). Decreased ferritin levels may result from either impaired iron transport associated with uteroplacental vascular insufficiency or increased iron utilization during enhanced erythropoiesis in conditions characterized by chronic fetal hypoxia. Our results stress the significance of iron supplementation and careful anemia follow-up in term SGA babies. Because anemia progress early, beginning iron therapy as soon as possible is a necessity in SGA babies as in prematures.     

Iron studies in infants born to an iron overloaded mother with beta-thalassemia major: possible effects of maternal desferrioxamine therapy

A 30-year-old woman with transfusion-dependent, homozygous beta-thalassemia major and transfusional hemosiderosis had 2 successful pregnancies after ovulation induction and in vitro fertilization. Treatment with subcutaneous desferrioxamine (DF) was discontinued before the conception but restarted at 6 months of gestation. Elective cesarean section was performed at 35 weeks of pregnancy because of partial placenta previa. The infant was clinically normal. At the time of delivery, the maternal serum ferritin was 2000 ng/mL, serum iron/iron binding capacity (SI/TIBC) were 274/380 microg/dL, and % saturation 72%. Serum ferritin level in the infant was 42 ng/mL, SI/TIBC were 53/222 microg/dL, and % saturation 23%. During a twin pregnancy 2 years later, DF therapy was totally withheld. Elective cesarian section was performed at 36 weeks of gestation. Both twins were clinically normal. At delivery, the maternal serum ferritin was 1700 ng/mL, SI/TIBC 447/450 microg/dL, and % saturation 99%. Serum ferritins of the twins were 227 and 203 ng/mL, SI/TIBC were 30/182 and 27/203 microg/dL, and % saturations 16% and 13%. Despite elevated iron studies in the mother during both pregnancies, the SI/TIBC of the infants were quite low. In the first pregnancy in which DF was administered in last months of gestation, a low level of serum ferritin was present in the newborn that was even lower at 3 months of age. In the second pregnancy, high normal, levels of ferritin were present in both twin newborns. Despite comparable gestational ages, hemoglobin levels were lower in the first pregnancy than the second. These studies indicate that very high maternal levels of SI/TIBS and serum ferritin were not associated with increased fetal SI/TIBC, which were, in fact, quite low. Because of the different fetal ferritin levels in the 2 pregnancies, it is possible that treatment of the mother with DF in the last weeks of pregnancy may have resulted in depletion of fetal iron stores.     

Influence of maternal diabetes mellitus on fetal iron status

OBJECTIVE: To determine the effects of maternal diabetes on fetal iron status using serum transferrin receptors (STfR) and their ratio to ferritin (TfR-F index) in cord blood. METHODS: Iron, ferritin, erythropoietin, STfR and haemoglobin concentration were measured and TfR-F index calculated in 97 maternal/cord blood pairs. Forty-nine women had type 1 diabetes (diagnosed before pregnancy) and these were compared with forty-eight non- diabetic controls. The women with type 1 diabetes were recruited consecutively from attendance at the joint antenatal endocrine clinic while the control group of women was recruited from consecutive attendance at the remaining antenatal clinics. RESULTS: The infants of the diabetic women had significantly lower levels of ferritin (47 vs 169 mug/l; p<0.01) and higher STfR (17.4 vs 12.9 mg/l; p<0.01) and TfR-F index (10.4 vs 5.8; p<0.01) than controls. They were also significantly more acidotic at birth (7.25 vs 7.30; p<0.01), were born at an earlier gestation (36.7 vs 39.7 weeks; p<0.01) and had higher z Scores for weight (0.53 vs 0.02; p = 0.016). CONCLUSIONS: Maternal diabetes causes depletion of fetal iron stores and is associated with higher fetal iron demands as indicated by higher STfR level and TfR-F index in cord blood.     

Serum copper in newborns and their mothers

Serum copper levels in the cord blood of 100 newborns and the respective maternal serum copper at the time of delivery was estimated by atomic absorption spectrophotometer. The cases were classified into term AGA, term SGA, term LGA, preterm AGA and preterm SGA. The mean maternal serum copper level 152.42 ± 2.06 μg/Jdl) was significantly higher than the mean cord serum copper level (39.84 ±1.19 μg/dl). There was positive correlation between the maternal serum copper level and cord serum copper level. The mean serum copper level of term neonates was (44.42 ± 1.26 μgJdl) significantly higher (p < 0.001) than that of preterm neonates (30.30 ± 1.14 μg/dl). There was a positive correlation between cord serum cooper level and gestational age. The mean cord serum copper levels of term AGA, term SGA, preterm AGA and preterm SGA neonates was 45.42 ± 1.44 μg/dl, 39.22 ± 2.45 μg/dl, 31.00 ± 2.11 udJdl and 29.47 ± 2.08 μg/dl respectively. There was no statistically significant difference in the mean serum copper level, of AGA and SGA group of both term and preterm noenates. The difference amongst mean maternal serum copper level of various neonatal groups was not significant.