Impact of multiple prenatal risk factors on newborn iron status at delivery

The Effects of Iron Administration on Anemia Development during the 7th and 21st Day of Life in Premature Newborns: A Prospective Cohort Study

Background and Objectives: The administration of iron to premature newborns is a common intervention aimed at preventing iron deficiency (ID). However, there is no consensus on the optimal timing and dosage for iron supplementation in this population. This study evaluates the effects and potential adverse outcomes of administering iron on the 7th and 21st days of life in premature infants. Materials and Methods: This research was conducted on 108 premature neonates at the "Louis Turcanu" Children's Emergency Clinical Hospital in Timisoara, Romania. The study population was divided into a control group of 48 newborns who did not receive iron supplementation and an intervention group of 60 newborns who did. The analysis utilized univariate and multivariate regression to examine binary outcomes. Results: The findings indicate that iron supplementation significantly increased the risk of anemia during the premature period at 21 days of life, as demonstrated by both univariate and multivariate regression analyses, with an odds ratio (OR) of 2.40 (95% CI, 1.01-5.68) and an adjusted odds ratio (AOR) of 2.75 (95% CI, 1.06-7.11), respectively. Contrary to expectations, iron supplementation did not significantly alter the risk of abnormal serum ferritin or iron levels at 21 days of life, according to the univariate analysis (p = 0.380 and p = 0.526, respectively). Conclusions: The observed increase in the risk of anemia without a corresponding improvement in the serum ferritin or iron levels suggests the need for further investigation into alternative strategies for iron supplementation in premature newborns.

Early-life adversity is associated with poor iron status in infancy

Exposure to early-life adversity (ELA) and iron deficiency early in life are known risk factors for suboptimal brain and socioemotional development. Iron deficiency may arise from and co-occur with ELA, which could negatively affect development. In the present study, we investigated whether ELA is associated with iron deficiency in infants receiving no iron supplementation. This study is a secondary analysis of extant data collected in the 1990s; participants were healthy infants from working-class communities in Santiago, Chile (N = 534, 45.5% female). We measured stressful life events, maternal depression, and low home support for child development during infancy and assessed iron status when the infant was 12 months old. Slightly more than half of the infants were iron-deficient (51%), and 25.8% were iron-deficient anemic at 12 months. Results indicated that ELA was associated with lower iron levels and iron deficiency at 12 months. The findings are consistent with animal and human prenatal models of stress and iron status and provide evidence of the association between postnatal ELA and iron status in humans. The findings also highlight a nutritional pathway by which ELA may impact development and present a nutritionally-focused avenue for future research on ELA and psychopathology.

Differentiation between fetal and postnatal iron deficiency in altering brain substrates of cognitive control in pre-adolescence

BACKGROUND

Early iron deficiency (ID) is a common risk factor for poorer neurodevelopment, limiting children's potential and contributing to global burden. However, it is unclear how early ID alters the substrate of brain functions supporting high-order cognitive abilities and whether the timing of early ID matters in terms of long-term brain development. This study aimed to examine the effects of ID during fetal or early postnatal periods on brain activities supporting proactive and reactive cognitive control in pre-adolescent children.

METHODS

Participants were part of a longitudinal cohort enrolled at birth in southeastern China between December 2008 and November 2011. Between July 2019 and October 2021, 115 children aged 8-11 years were invited to participate in this neuroimaging study. Final analyses included 71 children: 20 with fetal ID, 24 with ID at 9 months (postnatal ID), and 27 iron-sufficient at birth and 9 months. Participants performed a computer-based behavioral task in a Magnetic Resonance Imaging scanner to measure proactive and reactive cognitive control. Outcome measures included accuracy, reaction times, and brain activity. Linear mixed modeling and the 3dlme command in Analysis of Functional NeuroImages (AFNI) were separately used to analyze behavioral performance and neuroimaging data.

RESULTS

Faster responses in proactive vs. reactive conditions indicated that all groups could use proactive or reactive cognitive control according to contextual demands. However, the fetal ID group was lower in general accuracy than the other 2 groups. Per the demands of cues and targets, the iron-sufficient group showed greater activation of wide brain regions in proactive vs. reactive conditions. In contrast, such condition differences were reversed in the postnatal ID group. Condition differences in brain activation, shown in postnatal ID and iron-sufficient groups, were not found in the fetal ID group. This group specifically showed greater activation of brain regions in the reward pathway in proactive vs. reactive conditions.

CONCLUSIONS

Early ID was associated with altered brain functions supporting proactive and reactive cognitive control in childhood. Alterations differed between fetal and postnatal ID groups. The findings imply that iron supplement alone is insufficient to prevent persisting brain alterations associated with early ID. Intervention strategies in addition to the iron supplement should consider ID timing.

The effectiveness of a theory-based intervention program for pregnant women with anemia: A randomized control trial

Anemia in pregnancy is a public health concern. It has been diagnosed in 27% of pregnant women in Malaysia and up to 40% of pregnant women globally. This study aimed to develop and evaluate the effectiveness of an intervention initiative based on the health belief model. The MyPinkMom program was disseminated through a mobile messaging application to pregnant women to educate them on the prevention of anemia in pregnancy. We conducted a two-arm cluster-assignment, single-blinded, randomized control trial at two government antenatal clinics in Selangor. One clinic was randomly chosen as the intervention group, and the other was chosen as the control group. Sixty pregnant women with anemia from the intervention group received the MyPinkMom intervention program in the form of six infographic video clips, and 60 pregnant women with anemia from the control group received routine counseling on anemia in pregnancy. Pregnant women who had anemia secondary to hemoglobinopathy or other chronic diseases were excluded from this study. MANOVA showed significant increases in hemoglobin, knowledge, attitude, subjective norms, and perceived behavioral control scores for adherence to iron supplements, dietary iron, and dietary vitamin C intake (p < 0.001) in the intervention group at week 6. A significant reduction also occurred in dietary tannin intake (p < 0.001) in the intervention group at week 6. The intervention group at week 6 showed a large effect on hemoglobin level increments (partial eta squared, Ƞp2 0.268), dietary iron intake (Ƞp2 0.213), knowledge of anemia in pregnancy (Ƞp2 0.622), subjective norm scores for adherence to iron supplements (Ƞp2 0.167), and reduction in dietary tannin intake (Ƞp2 0.353). Similarly, repeated measures ANOVA showed that changes in hemoglobin levels were significantly different over time (i.e., at baseline, week 6, and week 12) between the intervention and control groups (p < 0.001). Hemoglobin increased rapidly over time among participants in the intervention group but gradually in the control group. To conclude, the newly developed MyPinkMom program that was delivered through a messaging application showed effectiveness in preventing anemia during pregnancy.

Impact and interactions between risk factors on the iron status of at-risk neonates

OBJECTIVE

Examine interactions between perinatal risk factors for congenital iron deficiency (ID) using two cohorts.

STUDY DESIGN

Iron status in a composite 767-member cord blood cohort and a NICU cohort of 257 infants < 33 weeks of gestation or small for gestational age (SGA). Risks for ID were examined. Cord ferritin levels < 84 µg/L defined congenital ID. Serum ferritin < 70 µg/L defined infantile ID at one-month.

RESULTS

31% of the cord cohort had congenital ID; risks summative (p < 0.0015). 16% of the NICU cohort had infantile ID; risks not summative. However, 32% had ID if the ferritin threshold was 100 µg/L. Being both preterm (p < 0.0001) and SGA (p < 0.05) negatively impacted cord iron status. Maternal hypertension was a novel predictor of iron status (p = 0.023 in preterm cord; p < 0.0025 in NICU).

CONCLUSION

Summing risks in term and understanding compounding risks in preterm infants can improve screening and management of ID in at-risk infants.

The Prevalence and Risk Factors of Iron Deficiency Anemia Among Pregnant Women in Malaysia: A Systematic Review

Anemia in pregnancy is defined as a hemoglobin level of <11 g/dl, and is commonly due to iron deficiency. This systematic review was conducted to determine the prevalence and risk factors of anemia and iron deficiency among pregnant women in Malaysia. A systematic literature search was conducted in Google Scholar, PubMed, and Cochrane Library databases. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guideline. Eight studies comprising a total number of 2,638 pregnant women were included in this review. Only two studies focused on iron deficiency, whereas the other six investigated anemia in pregnancy without specifying iron deficiency or any other nutritional cause for the anemia, signifying the lack of published literature on this important public health nutritional issue in Malaysia. The overall prevalence of anemia in pregnancy ranged from 19.3 to 57.4%, while the prevalence of iron deficiency was 31.6 to 34.6%. Factors that were significantly associated with anemia in pregnancy were extremes of reproductive age, late antenatal booking, non-compliance to hematinics, Indian ethnicity, being in the second or third trimester, low maternal educational level, low family income, and unemployment. The prevalence of anemia in pregnancy was found to be higher in rural compared to urban areas. Meanwhile, in terms of iron deficiency anemia, grandmultiparity, late antenatal booking and Indian ethnicity were significant determinants. It is certainly plausible that the anemia in pregnancy reported in these studies is not entirely secondary to iron deficiency and may be attributable to other nutritional deficiencies, emphasizing the importance of researching deeper into this subject. Nevertheless, in the meantime, focusing on iron supplementation in high-risk mothers with emphasis on compliance, seems to be the best option, in view of the high prevalence of iron deficiency found in this review.

Timing of iron deficiency and recognition memory in infancy

Objective: To determine the relationship between iron deficiency (or iron-deficient, ID) and neural correlates of recognition memory depending on ID timing (gestation vs. infancy) and infant age at testing (9 vs. 18 months).Study design: Event-related potentials (ERP) were used in a visual recognition memory task (mother vs. stranger face) to compare healthy term infants according to iron status at birth and 9 months. Fetal-neonatal ID was defined as cord serum ferritin < 75 µg/l or zinc protoporphrin/heme ratio > 118 µmol/mol, postnatal ID as ≥ 2 abnormal iron measures at 9 months with normal cord-blood iron status, and iron-sufficient as not ID at birth or 9 months. Recognition of mother faces was measured by negative component (Nc) and late slow wave (LSW). These ERP components reflect attention and memory updating processes, respectively.Results: All groups showed differences in Nc amplitude elicited by mother and stranger faces at 9 months. At 18 months, only postnatal ID and iron-sufficient groups showed condition differences in Nc amplitude. However, the 2 groups were different in the involved brain regions. For LSW, only the 2 ID groups showed condition differences in amplitude at 9 months. At 18 months, condition differences were not observed in any group.Conclusions: This study indicates that the timing of ID in early life (fetal-neonatal vs. postnatal) modulates the impact of ID on recognition memory. Such impact also varies depending on the age of infants at testing (9 vs. 18 months).

Urinary ferritin; a potential noninvasive way to screen NICU patients for iron deficiency

OBJECTIVE

Building on our previous study, showing a correlation between ferritin in serum and urine, we conducted a feasibility evaluation, measuring urinary ferritin as a potential noninvasive screening test for iron deficiency among NICU patients.

STUDY DESIGN

This was a prospective analysis of paired serum/urine ferritin levels. We defined iron-limited erythropoiesis by a RET-He <5th percentile lower reference interval (<28 pg).

RESULTS

We obtained 49 paired serum/urine samples from neonates judged as at-risk for iron deficiency. Urine ferritin ("corrected" for urine creatinine and specific gravity) correlated with serum ferritin (correlation coefficient of log₁₀-transformed values 0.44). A corrected urine ferritin <12 ng/mL had a sensitivity of 82% (95% CI, 67-93%) and a specificity of 100% (CI, 66-100%) for detecting iron-limited erythropoiesis, with a positive predictive value of 100% (CI, 89-100%).

CONCLUSIONS

Measuring urinary ferritin in NICU patients is feasible. Since low values identify iron-limitation, this could become a useful noninvasive screen.

Are Pregnant Women Who Are Living with Overweight or Obesity at Greater Risk of Developing Iron Deficiency/Anaemia?

Low-grade inflammation is often present in people living with obesity. Inflammation can impact iron uptake and metabolism through elevation of hepcidin levels. Obesity is a major public health issue globally, with pregnant women often affected by the condition. Maternal obesity is associated with increased pregnancy risks including iron deficiency (ID) and iron-deficiency anaemia (IDA)-conditions already highly prevalent in pregnant women and their newborns. This comprehensive review assesses whether the inflammatory state induced by obesity could contribute to an increased incidence of ID/IDA in pregnant women and their children. We discuss the challenges in accurate measurement of iron status in the presence of inflammation, and available iron repletion strategies and their effectiveness in pregnant women living with obesity. We suggest that pre-pregnancy obesity and overweight/obese pregnancies carry a greater risk of ID/IDA for the mother during pregnancy and postpartum period, as well as for the baby. We propose iron status and weight gain during pregnancy should be monitored more closely in women who are living with overweight or obesity.

Early iron supplementation and iron sufficiency at one month of age in NICU patients at-risk for iron deficiency

In order to reduce iron deficiency in neonates at-risk for iron deficiency, we implemented a guideline to increase the consistency of early iron supplementation in infants of diabetic mothers, small for gestational age neonates and very low birthweight premature neonates. Three years following implementation we performed a retrospective analysis in order to assess adherence to the guideline and to compare timing of early iron supplementation and reticulocyte-hemoglobin (RET-He) values at one month of life in at-risk infants. Adherence with early iron supplementation guidelines was 73.4% (399/543) with 51% (275/543) having RET-He values obtained at one month. Despite good adherence, 16% (44/275) had RET-He <25 pg (5th percentile for gestational age). No infants receiving red blood cell transfusion (0/20) had RET-He <25 pg vs. 26.1% (40/153) of those treated with darbepoetin (p < 0.001). There was no evidence of increased feeding intolerance (episodes of emesis/day) with early iron supplementation.

Iron Nutrition, Erythrocytes, and Erythropoietin in the NICU: Erythropoietic and Neuroprotective Effects

Prematurity, maternal diabetes, maternal smoking, being medically underserved, and small size for gestational age are common characteristics of neonates in the NICU and can predispose them to develop congenital iron deficiency. Iron is critical for organ development. In the fetus and newborn, iron is prioritized for red blood cell production, sometimes at the expense of other tissues, including the brain. It is critical to optimize iron levels in newborns to support erythropoiesis, growth, and brain development. Available studies support improved neurodevelopmental outcomes with either iron supplementation or delayed umbilical cord clamping at birth. Erythropoietic doses of erythropoietin/erythrocyte-stimulating agents may also improve neurocognitive outcomes. However, the literature on the effect of liberal red blood cell transfusions on long-term neurodevelopment is mixed. Understanding age-specific normal values and monitoring of iron indices can help individualize and optimize the iron status of patients in the NICU.

Contribution of iron status at birth to infant iron status at 9 months: data from a prospective maternal-infant birth cohort in China

BACKGROUND/OBJECTIVES

The contribution of iron status at birth to iron status in infancy is not known. We used a physiologic framework to evaluate how iron status at birth related to iron status at 9 months, taking iron needs and sources into account.

SUBJECTS/METHODS

In a longitudinal birth cohort in China, iron status measures in cord blood and venous blood in infancy (9 months) and clinical data were prospectively collected in 545 healthy term maternal–infant dyads. We used structural equation modeling (SEM) to create a 9-month iron composite and to assess direct and indirect contributions of multiple influences on 9-month iron status. Logistic regression was used to calculate odds ratios (OR) for iron deficiency (ID), iron deficiency anemia (IDA), and anemia.

RESULTS

Approximately 15% (78/523) of infants were born with cord SF<75 μg/l, suggesting fetal-neonatal ID. At 9 months, 34.8% (186/535) and 19.6% (105/535) of infants had ID and IDA, respectively. The following factors were independently associated with poorer 9-month iron status: higher cord zinc protoporphyrin/heme (ZPP/H) (adjusted estimate −0.18, P< 0.001) and serum transferrin receptor (sTfR) (−0.11, P=0.004), lower cord hemoglobin (Hb) (0.13, P=0.004), lower birth weight (0.15, P< 0.001), male sex (0.10, P=0.013), older age at testing (−0.26, P<0.001), higher 9-month weight (−0.12, P=0.006) and breastfeeding (0.38, P<0.001). Breastfeeding at 9 months showed the strongest association, adjusting for all other factors. Compared to formula-fed infants, the odds of IDA were 19.1 (95%CI: 6.92, 52.49, P< 0.001) and 3.6 (95%CI: 1.04, 12.50, P=0.043) times higher in breastfed and mixed-fed infants, respectively.

CONCLUSIONS

Indicators of iron status at birth, postnatal iron needs, and iron sources independently related to iron status at 9 months. Sex was an additional factor. Public health policies to identify and protect infants at increased risk of ID should be prioritized.

Screening umbilical cord blood for congenital Iron deficiency

OBJECTIVES

Small for gestational age infants (SGA), infants of diabetic mothers (IDM), and very low birth weight infants (VLBW) are at risk for congenital iron deficiency. We evaluated the iron status of SGA, IDM, and VLBW neonates at birth and sought mechanistic explanations in those with iron deficiency.

METHODS

This was a prospective study. If congenital iron deficiency was present, maternal iron studies were obtained. When neonates were two weeks old, their iron status was reevaluated.

RESULTS

Sixteen of 180 neonates screened were iron deficient at birth. The Body Mass Index of the 16 mothers was high. These mothers often had mild iron deficiency and measurable hepcidin levels. Two weeks after birth, neonates had improved iron measurements.

CONCLUSIONS

Among SGA, IDM, and VLBW neonates, maternal obesity is a risk factor for congenital iron deficiency. We speculate that elevated hepcidin levels in obese pregnant women impede iron absorption and interfere with transplacental iron transfer.

Cord Blood Erythropoietin and Hepcidin Reflect Lower Newborn Iron Stores due to Maternal Obesity during Pregnancy

OBJECTIVE

Obesity during pregnancy impedes fetal iron endowment. In adults, both iron depletion and hypoxia stimulate erythropoietin (Epo) production, while hepcidin, the primary iron regulator, is inhibited by Epo and stimulated by obesity. To understand this relationship in fetuses, we investigated obesity, inflammation, and fetal iron status on fetal Epo and hepcidin levels.

STUDY DESIGN

Epo, hepcidin, C-reactive protein (CRP), and ferritin levels were measured in 201 newborns of 35 to 40 weeks' gestation with historical risk factors for a low fetal iron endowment, including half with maternal obesity.

RESULTS

Epo was unrelated to fetal size, but Epo was directly related to maternal body mass index (BMI; kg/m²) (p < 0.03) and CRP (p < 0.0005) at delivery. Epo levels were twice as likely to be elevated (≥50 IU/L) while comparing the lowest quartile of ferritin with the upper three quartiles (p < 0.01). Hepcidin was directly related to ferritin (p < 0.001) and indirectly related to maternal BMI (p < 0.015), but BMI became nonsignificant when undergoing multivariate analysis. Hepcidin was unrelated to Epo.

CONCLUSION

Although some of the fetal responses involving Epo were similar to adults, we did not find a hepcidin-Epo relationship like that of adults, where fetal liver is the site of both hepcidin and Epo production.

Maternal Perceived Stress during Pregnancy Increases Risk for Low Neonatal Iron at Delivery and Depletion of Storage Iron at One Year

OBJECTIVE

To investigate the impact of maternal stress during pregnancy on newborn iron and stage 1 iron deficiency at 1 year of age.

STUDY DESIGN

In total, 245 mothers and their newborn infants (52% male; 72% white) were recruited at the Meriter Hospital Birthing Center on the basis of known risk factors for iron deficiency. Umbilical cord blood hemoglobin and zinc protoporphyrin/heme (ZnPP/H) were determined to evaluate erythrocyte iron and plasma ferritin was determined to reflect storage iron. Mothers retrospectively reported stress experienced previously during pregnancy on a 25-item questionnaire. Blood was also was collected from 79 infants who were breastfed at 1 year of age.

RESULTS

Maternal recall of distress and health concerns during pregnancy correlated with cord blood ZnPP/H indices (r = 0.21, P < .01), even in the absence of major traumatic events. When concurrent with other known risks for iron deficiency, including maternal adiposity, socioeconomic status, and race, maternal stress had a summative effect, lowering cord blood iron. At 1 year, 24% of infants who were breastfed had moderate iron deficiency (plasma ferritin <12 µg/L). Higher cord blood ZnPP/H was predictive of this moderate iron deficiency (95% CI 0.26-1.47, P = .007). When coincident with maternal reports of gestational stress, the likelihood of low plasma ferritin at 1 year increased 36-fold in breastfed infants as compared with low-stress pregnancies (95% CI 1.33-6.83, P = .007).

CONCLUSIONS

Maternal recall of stress during pregnancy was associated with lower iron stores at birth. High cord blood ZnPP/H, reflecting low erythrocyte iron, was correlated with the likelihood of stage 1 iron deficiency at 1 year, when rapid growth can deplete storage iron in breastfed infants.

Zinc protoporphyrin/heme ratio as parameter of iron status in moderately preterm infants: natural course and associations in the first 4 months

OBJECTIVE

To determine the natural course of zinc protoporphyrin/heme ratio (ZnPP/H) and its role in the detection of iron deficiency (ID) and iron-deficiency anemia (IDA) in the first 4 months of life in moderately preterm infants.

STUDY DESIGN

ZnPP/H was measured at 1 week, 6 weeks and 4 months postnatal age in a prospective cohort of 161 Dutch infants born at a gestational age of 32+0 to 36+6 weeks who did not receive an erythrocyte transfusion or iron supplementation.

RESULTS

ZnPP/H levels decreased in the first 6 weeks and increased thereafter. At 4 months postnatal age, ZnPP/H was higher in the 11 (8.5%) infants with IDA (mean (s.d.): 260.8 (16.1)) but not in the 27 (21.3%) infants with ID (mean (s.d.): 177.0 (15.1)) compared with normal infants (mean (s.d.): 157.3 (12.5)).

CONCLUSION

In moderately preterm infants, ZnPP/H can be of additional value to detect infants at risk for IDA due to iron-deficient erythropoiesis at 4 months of age.

Breastfeeding, Mixed, or Formula Feeding at 9 Months of Age and the Prevalence of Iron Deficiency and Iron Deficiency Anemia in Two Cohorts of Infants in China

OBJECTIVE

To assess associations between breastfeeding and iron status at 9 months of age in 2 samples of Chinese infants.

STUDY DESIGN

Associations between feeding at 9 months of age (breastfed as sole milk source, mixed fed, or formula fed) and iron deficiency anemia (IDA), iron deficiency, and iron sufficiency were determined in infants from Zhejiang (n = 142) and Hebei (n= 813) provinces. Iron deficiency was defined as body iron < 0 mg/kg, and IDA as iron deficiency + hemoglobin < 110 g/L. Multiple logistic regression assessed associations between feeding pattern and iron status.

RESULTS

Breastfeeding was associated with iron status (P < .001). In Zhejiang, 27.5% of breastfed infants had IDA compared with 0% of formula-fed infants. The odds of iron deficiency/IDA were increased in breastfed and mixed-fed infants compared with formula-fed infants: breastfed vs formula-fed OR, 28.8 (95% CI, 3.7-226.4) and mixed-fed vs formula-fed OR, 11.0 (95% CI, 1.2-103.2). In Hebei, 44.0% of breastfed infants had IDA compared with 2.8% of formula-fed infants. With covariable adjustment, odds of IDA were increased in breastfed and mixed-fed groups: breastfed vs formula-fed OR, 78.8 (95% CI, 27.2-228.1) and mixed-fed vs formula-fed OR, 21.0 (95% CI, 7.3-60.9).

CONCLUSIONS

In both cohorts, the odds of iron deficiency/IDA at 9 months of age were increased in breastfed and mixed-fed infants, and iron deficiency/IDA was common. Although the benefits of breastfeeding are indisputable, these findings add to the evidence that breastfeeding in later infancy identifies infants at risk for iron deficiency/IDA in many settings. Protocols for detecting and preventing iron deficiency/IDA in breastfed infants are needed.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00642863 and NCT00613717.

Impact of maternal, antenatal and birth-associated factors on iron stores at birth: data from a prospective maternal-infant birth cohort

BACKGROUND/OBJECTIVES

Low serum ferritin concentrations at birth, which reflect neonatal iron stores, track through to early childhood and have been associated with poorer neurodevelopmental outcomes. We aimed to identify maternal, antenatal and birth-associated factors that influence iron stores at birth in a prospective maternal-infant birth cohort.

SUBJECTS/METHODS

In a population-based, longitudinal, birth cohort in Ireland, 413 maternal-infant dyads with prospectively collected lifestyle and clinical data from 15 weeks' gestation had umbilical cord serum ferritin concentrations measured. Regression models were developed to identify independent factors associated with cord ferritin concentrations.

RESULTS

Median (IQR) cord ferritin concentrations were 185.7 (131.7, 385.5) μg/l, and 8% (n=33) of infants had low iron stores (ferritin <76 μg/l) at birth. Maternal obesity (BMI ⩾30 kg/m²) at 15 weeks' gestation (adj. estimate (95% confidence interval (CI)): -66.4 (-106.9, -25.9) μg/l, P<0.0001) and delivery by caesarean section (-38.8 (-70.2, -7.4) μg/l, P=0.016) were inversely associated with cord ferritin concentrations. In addition, maternal smoking at 15 weeks' gestation (adj. odds ratio (95% CI): 2.9 (1.2, 7), P=0.020) and being born small-for-gestational age (3.4 (1.3, 8.9), P=0.012) were associated with an increased risk of low iron stores (ferritin <76 μg/l) at birth.

CONCLUSIONS

We have identified a number of potentially modifiable lifestyle factors that influence iron stores at birth, with the important role of overall maternal health and lifestyle during pregnancy highlighted. Public health policies targeting women of child-bearing age to improve nutrition and health outcomes should be prioritised for the health of the next generation.

Maternal Obesity Affects Inflammatory and Iron Indices in Umbilical Cord Blood

OBJECTIVE

To determine the impact of maternal obesity and gestational weight gain across pregnancy on fetal indices of inflammation and iron status.

STUDY DESIGN

Eighty-five healthy term newborns delivered via elective cesarean were categorized by 2 maternal body mass index (BMI) thresholds; above or below 30 kg/m(2) or above or below 35 kg/m(2). Umbilical cord plasma levels of C-reactive protein, interleukin (IL)-6, tumor necrosis factor (TNF)-α, ferritin, and hepcidin were assayed. Cytokines released by phytohemagglutinin-stimulated umbilical cord mononuclear cells (MNCs) were assayed.

RESULTS

Maternal class II obesity, defined as BMI of 35 kg/m(2) and above, predicted higher C-reactive protein and TNF-α in umbilical cord plasma (P < .05 for both), and also proinflammatory cytokines (IL-1β, IL-6, and TNF-α) from stimulated MNC (P < .05 for all). The rise in plasma TNF-α and MNC TNF-α was not linear but occurred when the threshold of BMI 35 kg/m(2) was reached (P < .005, P < .06). Poorer umbilical cord iron indices were associated with maternal obesity. When ferritin was low, IL-6 was higher (P < .04), but this relationship was present primarily when maternal BMI exceeded 35 kg/m(2) (P < .03). Ferritin was correlated with hepcidin (P < .0001), but hepcidin was unrelated to either maternal BMI or inflammatory indices.

CONCLUSIONS

Class II obesity and above during pregnancy is associated with fetal inflammation in a threshold fashion. Although maternal BMI negatively impacted fetal iron status, hepcidin, related to obesity in adults, was related to iron status and not obesity in fetuses. Pediatricians should be aware of these relationships.

Impact of Growth Restriction and Other Prenatal Risk Factors on Cord Blood Iron Status in Prematurity

OBJECTIVE

To determine whether prenatal risk factors (RFs) that predict cord blood iron status in term newborns also predict iron status of premature newborns.

STUDY DESIGN

Cord blood iron indices from 80 preterm newborns were compared with historical and demographic RFs for developing iron deficiency if born at term.

RESULT

The presence of multiple RFs did not incrementally interfere with cord iron status in preterm newborns. Poorer iron status accompanied being small for gestational age in prematurity, but other RFs, including diabetes, had relatively little impact.

CONCLUSION

Growth-restricted preterm newborns are at risk for poor iron endowment, likely due to uteroplacental insufficiency. Other RFs were less impactful on iron status of premature newborns than in term newborns, likely reflecting that disruptive effects of RFs are more impactful in the third trimester. Understanding RFs for poor iron endowment is important for clinical recognition and treatment of premature babies.

Does Body Mass Index in Pregnant Women Affect Laboratory Parameters in the Newborn?

Objective The objective of this study was to determine the effect of body mass index (BMI) during pregnancy in laboratory parameters in the serum of the three groups of pregnant women and in their newborns. Methods This prospective study is comparison between the three groups of pregnant women and their newborns categorized according to their BMI. The study included 128 pregnant women and their newborns. In this study, the concentration of blood count, iron, ferritin, and bilirubin were analyzed in the subjects. Results The pregnant women in the three groups significantly differ in the values of blood count (p < 0.001). Statistically significant difference in iron and ferritin was not found between individual three studied groups of pregnant women (p = 0.947). The newborn of the first group of pregnant women had significantly lower values of ferritin (p < 0.001), leucocytes (p < 0.001), and bilirubin (p < 0.001). Significant positive correlation between BMI of pregnant women and leucocytes, ferritin, and bilirubin of the newborn was found (p < 0.001). Conclusion In this study, the tested pregnant women do not have biochemical signs of anemia, neither do their newborns. It was noted that there was no negative correlation between individual tested biochemical parameters for anemia in pregnant women and their newborns.

Low-Dose Iron Supplementation in Infancy Modestly Increases Infant Iron Status at 9 Mo without Decreasing Growth or Increasing Illness in a Randomized Clinical Trial in Rural China

BACKGROUND

Previous trials of iron supplementation in infancy did not consider maternal iron supplementation.

OBJECTIVE

This study assessed effects of iron supplementation in infancy and/or pregnancy on infant iron status, illnesses, and growth at 9 mo.

METHODS

Enrollment occurred from December 2009 to June 2012 in Hebei, China. Infants born to women in a pregnancy iron supplementation trial were randomly assigned 1:1 to iron [∼1 mg Fe/(kg · d) as oral iron proteinsuccynilate] or placebo from 6 wk to 9 mo, excluding infants with cord ferritin <35 μg/L. Study groups were pregnancy placebo/infancy placebo (placebo/placebo), pregnancy placebo/infancy iron (placebo/iron), pregnancy iron/infancy placebo (iron/placebo), and pregnancy iron/infancy iron (iron/iron). The primary outcome was 9-mo iron status: iron deficiency (ID) by cutoff (≥2 abnormal iron measures) or body iron <0 mg/kg and ID + anemia (hemoglobin <110 g/L). Secondary outcomes were doctor visits or hospitalizations and weight or length gain from birth to 9 mo. Statistical analysis by intention to treat and dose-response (between number of iron bottles received and outcome) used logistic regression with concomitant RRs and general linear models, with covariate control as applicable.

RESULTS

Of 1482 infants randomly allocated, 1276 had 9-mo data (n = 312-327/group). Iron supplementation in infancy, but not pregnancy, reduced ID risk: RRs (95% CIs) were 0.89 (0.79, 0.998) for placebo/iron compared to placebo/placebo, 0.79 (0.63, 0.98) for placebo/iron compared to iron/placebo, 0.87 (0.77, 0.98) for iron/iron compared to placebo/placebo, and 0.86 (0.77, 0.97) for iron/iron compared to iron/placebo. However, >60% of infants still had ID at 9 mo. Receiving more bottles of iron in infancy was associated with better infant iron status at 9 mo but only among iron-supplemented infants whose mothers were also iron supplemented (i.e., the iron/iron group). There were no group differences in hospitalizations or illnesses and no adverse effects on growth overall or among infants who were iron sufficient at birth.

CONCLUSIONS

Iron supplementation in Chinese infants reduced ID at 9 mo without adverse effects on growth or illness. Effects of iron supplementation in pregnancy were observed only when higher amounts of iron were distributed in infancy. This trial was registered at clinicaltrials.gov as NCT00613717.

Iron deficiency (ID) at both birth and 9 months predicts right frontal EEG asymmetry in infancy

This study considered effects of timing and duration of iron deficiency (ID) on frontal EEG asymmetry in infancy. In healthy term Chinese infants, EEG was recorded at 9 months in three experimental conditions: baseline, peek-a-boo, and stranger approach. Eighty infants provided data for all conditions. Prenatal ID was defined as low cord ferritin or high ZPP/H. Postnatal ID was defined as ≥ two abnormal iron measures at 9 months. Study groups were pre- and postnatal ID, prenatal ID only, postnatal ID only, and not ID. GLM repeated measure analysis showed a main effect for iron group. The pre- and postnatal ID group had negative asymmetry scores, reflecting right frontal EEG asymmetry (mean ± SE: -.18 ± .07) versus prenatal ID only (.00 ± .04), postnatal ID only (.03 ± .04), and not ID (.02 ± .04). Thus, ID at both birth and 9 months was associated with right frontal EEG asymmetry, a neural correlate of behavioral withdrawal and negative emotions.

Impact of Fetal-Neonatal Iron Deficiency on Recognition Memory at 2 Months of Age

OBJECTIVE

To assess the effects of fetal-neonatal iron deficiency on recognition memory in early infancy. Perinatal iron deficiency delays or disrupts hippocampal development in animal models and thus may impair related neural functions in human infants, such as recognition memory.

STUDY DESIGN

Event-related potentials were used in an auditory recognition memory task to compare 2-month-old Chinese infants with iron sufficiency or deficiency at birth. Fetal-neonatal iron deficiency was defined 2 ways: high zinc protoporphyrin/heme ratio (ZPP/H > 118 μmol/mol) or low serum ferritin (<75 μg/L) in cord blood. Late slow wave was used to measure infant recognition of mother's voice.

RESULTS

Event related potentials patterns differed significantly for fetal-neonatal iron deficiency as defined by high cord ZPP/H but not low ferritin. Comparing 35 infants with iron deficiency (ZPP/H > 118 μmol/mol) to 92 with lower ZPP/H (iron-sufficient), only infants with iron sufficiency showed larger late slow wave amplitude for stranger's voice than mother's voice in frontal-central and parietal-occipital locations, indicating the recognition of mother's voice.

CONCLUSIONS

Infants with iron sufficiency showed electrophysiological evidence of recognizing their mother's voice, whereas infants with fetal-neonatal iron deficiency did not. Their poorer auditory recognition memory at 2 months of age is consistent with effects of fetal-neonatal iron deficiency on the developing hippocampus.

Prenatal Iron Supplementation Reduces Maternal Anemia, Iron Deficiency, and Iron Deficiency Anemia in a Randomized Clinical Trial in Rural China, but Iron Deficiency Remains Widespread in Mothers and Neonates

BACKGROUND

Previous trials of prenatal iron supplementation had limited measures of maternal or neonatal iron status.

OBJECTIVE

The purpose was to assess effects of prenatal iron-folate supplementation on maternal and neonatal iron status.

METHODS

Enrollment occurred June 2009 through December 2011 in Hebei, China. Women with uncomplicated singleton pregnancies at ≤20 wk gestation, aged ≥18 y, and with hemoglobin ≥100 g/L were randomly assigned 1:1 to receive daily iron (300 mg ferrous sulfate) or placebo + 0.40 mg folate from enrollment to birth. Iron status was assessed in maternal venous blood (at enrollment and at or near term) and cord blood. Primary outcomes were as follows: 1) maternal iron deficiency (ID) defined in 2 ways as serum ferritin (SF) <15 μg/L and body iron (BI) <0 mg/kg; 2) maternal ID anemia [ID + anemia (IDA); hemoglobin <110 g/L]; and 3) neonatal ID (cord blood ferritin <75 μg/L or zinc protoporphyrin/heme >118 μmol/mol).

RESULTS

A total of 2371 women were randomly assigned, with outcomes for 1632 women or neonates (809 placebo/folate, 823 iron/folate; 1579 mother-newborn pairs, 37 mothers, 16 neonates). Most infants (97%) were born at term. At or near term, maternal hemoglobin was significantly higher (+5.56 g/L) for iron vs. placebo groups. Anemia risk was reduced (RR: 0.53; 95% CI: 0.43, 0.66), as were risks of ID (RR: 0.74; 95% CI: 0.69, 0.79 by SF; RR: 0.65; 95% CI: 0.59, 0.71 by BI) and IDA (RR: 0.49; 95% CI: 0.38, 0.62 by SF; RR: 0.51; 95% CI: 0.40, 0.65 by BI). Most women still had ID (66.8% by SF, 54.7% by BI). Adverse effects, all minor, were similar by group. There were no differences in cord blood iron measures; >45% of neonates in each group had ID. However, dose-response analyses showed higher cord SF with more maternal iron capsules reported being consumed (β per 10 capsules = 2.60, P < 0.05).

CONCLUSIONS

Prenatal iron supplementation reduced anemia, ID, and IDA in pregnant women in rural China, but most women and >45% of neonates had ID, regardless of supplementation. This trial was registered at clinicaltrials.gov as NCT02221752.

Maternal pregnancy weight gain and cord blood iron status are associated with eosinophilia in infancy

OBJECTIVE

Allergic disease is multifactorial in origin. Because iron nutrition affects immune responses and maternal pregnancy weight gain impairs fetal iron delivery while increasing fetal demands for growth, the study examined maternal pregnancy weight gain, newborn iron status and an index of atopic disease, infant eosinophilia.

STUDY DESIGN

Within a larger prospective study of healthy newborns at risk for developing iron deficiency anemia, umbilical cord iron indicators were compared to infant eosinophil counts.

RESULT

Infants who developed eosinophilia exhibited higher cord reticulocyte-enriched zinc protoporphyrin/heme ratio, P<0.05 and fewer cord ferritin values in the highest (best) quartile, P<0.05. If cord ferritin was in the upper three quartiles, the negative predictive value for infant eosinophilia was 90%. High maternal pregnancy weight gain predicted infant eosinophil counts, P<0.04, and contributed to cord ferritin predicting eosinophilia, P<0.003.

CONCLUSION

Poor fetal iron status may be an additional risk factor for infant eosinophilia.

Neonatal iron status is impaired by maternal obesity and excessive weight gain during pregnancy

OBJECTIVE

Maternal iron needs increase sixfold during pregnancy, but obesity interferes with iron absorption. We hypothesized that maternal obesity impairs fetal iron status.

STUDY DESIGN

Three hundred and sixteen newborns with risk factors for infantile iron deficiency anemia (IDA) were studied to examine obesity during pregnancy and neonatal iron status. Erythrocyte iron was assessed by cord blood hemoglobin (Hb), zinc protoporphyrin/heme (ZnPP/H) and reticulocyte-ZnPP/H, and storage iron by serum ferritin.

RESULT

Women with body mass index (BMI) ⩾ 30 kg m(-)(2), as compared with non-obese women, delivered larger offspring with higher reticulocyte-ZnPP/H and lower serum ferritin concentrations (P<0.05 for both). With increasing BMI, the estimated body iron was relatively lower (mg kg(-)(1)) and the ratio of total Hb-bound iron (mg) per total body iron (mg) increased. Maternal diabetes compromised infant iron status, but multivariate analysis demonstrated that obesity was an independent predictor.

CONCLUSION

Obesity during pregnancy and excessive weight gain are independent risk factors for iron deficiency in the newborn.

The influences of factors associated with decreased iron supply to the fetus during pregnancy on iron status in healthy children aged 0.5 to 3 years

OBJECTIVE

To investigate whether maternal anemia, pregnancy-induced diabetes, hypertension and smoking contributed to the recently found high prevalence of iron deficiency in a population of otherwise healthy children.

STUDY DESIGN

Iron status was assessed in 400 children aged 0.5 to 3 years. We obtained information on the mothers' laboratory results, the presence of diabetes and hypertension, smoking habits and use of medication while pregnant.

RESULT

We found no influence of maternal anemia, diabetes, hypertension or smoking during pregnancy on iron status in the children. Mean corpuscular volume (MCV) values of the children were positively correlated to maternal MCV values.

CONCLUSION

In this population, iron status in children is not affected by maternal anemia or maternal factors that are associated with a decreased iron transport during pregnancy. The correlation between MCV values in mothers and their children might be explained by genetic and/or shared environmental factors.

Low-level prenatal lead exposure alters auditory recognition memory in 2-month-old infants: an event-related potentials (ERPs) study

This study used event-related potentials (ERPs) to assess effects of low-level prenatal lead exposure on auditory recognition memory in 2-month-old infants. Infants were divided into four groups according to cord-blood lead concentration: (1) <2.00 μ g/dL, (2) 2.00-2.99 μ g/dL, (3) 3.0-3.7 μ g/dL, and (4) ≥3.7 μ g/dL. The first group showed the normally expected differences in P2, P750, and late slow wave (LSW) amplitudes elicited by mothers' and strangers' voices. These differences were not observed for one or more ERP components in the other groups. Thus, there was electrophysiological evidence of poorer auditory recognition memory at 2 months with cord-blood lead ≥2.00 μ g/dL.

Latent iron deficiency in utero is associated with abnormal auditory neural myelination in ≥ 35 weeks gestational age infants

OBJECTIVE

To determine whether cord serum ferritin level is associated with auditory brainstem evoked response interpeak latencies, an index of auditory neural myelination, in infants at ≥ 35 weeks gestational age (GA).

STUDY DESIGN

This prospective study compared auditory neural myelination in infants with latent iron deficiency (cord serum ferritin, 11-75 ng/mL) and infants with normal iron status (cord serum ferritin, >75 ng/mL) at birth. Our inclusion criteria were infants born at ≥ 35 weeks GA who had cord blood collected soon after birth and had 1 or more of the following risk factors for poor in utero iron status: maternal diabetes mellitus, pregnancy-induced hypertension, and intrauterine growth restriction. Cord serum ferritin level was measured using the chemiluminescence immunoassay method. Auditory brainstem evoked response was measured using 80-dB normal hearing level click stimuli at a rate of 69.9/second within 48 hours after birth to evaluate interpeak latencies, a measure of nerve conduction velocity or myelination.

RESULTS

Of the 45 infants studied, 12 had latent iron deficiency. On repeated-measures ANCOVA using interpeak latencies I-III, III-V, and I-V as multiple outcomes, infants with latent iron deficiency had significantly prolonged interpeak latencies (P = .01) compared with infants with normal iron status after controlling for confounders.

CONCLUSION

In utero latent iron deficiency is associated with abnormal auditory neural myelination at birth in infants born at ≥ 35 weeks GA.