Maternal iron status: relation to fetal growth, length of gestation, and iron endowment of the neonate

Maternal anemia associated with walkable distance to healthy food sources in Bronx, New York

The relationship between walkable access to healthy food sources and risk of anemia in pregnancy was evaluated for a cohort of 4678 women who initiated prenatal care in the year 2010 at an academic medical center in Bronx, New York. After geocoding patient residences, street network distances were obtained for the closest healthy food sources, which were identified from multiple databases. For lower-income patients, as indicated by Medicaid or lack of health insurance, those who lived less than 0.25miles from a healthy food source were less likely to be anemic when compared to those who lived farther (adjusted OR=0.65, 95% CI 0.48, 0.88). Patients with commercial insurance showed no effect. These results help to understand how a nutritionally-mediated condition such as anemia during pregnancy can be affected by one's built environment, while also highlighting the importance of conditioning on socioeconomic status for these types of studies.

Transferrin Sialylation in Smoking and Non-Smoking Pregnant Women with Intrauterine Growth Restriction

Transferrin (Tf) is a glycosylated protein responsible for transporting iron. Various sialylation levels of Tf are observed during physiological and pathological processes. We studied if the changes in iron stores as well as tobacco smoke may have an impact on foetal development and in consequence lead to intrauterine growth restriction (IUGR). In the third trimester of pregnancy, lower levels of 4-sialoTf isoform and higher levels of 5-sialoTf were observed in the serum of non-smoking women with IUGR in comparison to the control group. On the day of labour, level of 2-sialoTf was significantly lower and level of 3-sialo was Tf higher in the serum of non-smoking women. Level of 4-sialo was found lower in the serum of smoking women with IUGR than in the control group. The observed changes may suggest a connection between iron stores, transport of iron to the foetus and foetal development.

A review of the impact of dietary intakes in human pregnancy on infant birthweight

Studies assessing maternal dietary intakes and the relationship with birthweight are inconsistent, thus attempting to draw inferences on the role of maternal nutrition in determining the fetal growth trajectory is difficult. The aim of this review is to provide updated evidence from epidemiological and randomized controlled trials on the impact of dietary and supplemental intakes of omega-3 long-chain polyunsaturated fatty acids, zinc, folate, iron, calcium, and vitamin D, as well as dietary patterns, on infant birthweight. A comprehensive review of the literature was undertaken via the electronic databases Pubmed, Cochrane Library, and Medline. Included articles were those published in English, in scholarly journals, and which provided information about diet and nutrition during pregnancy and infant birthweight. There is insufficient evidence for omega-3 fatty acid supplements’ ability to reduce risk of low birthweight (LBW), and more robust evidence from studies supplementing with zinc, calcium, and/or vitamin D needs to be established. Iron supplementation appears to increase birthweight, particularly when there are increases in maternal hemoglobin concentrations in the third trimester. There is limited evidence supporting the use of folic acid supplements to reduce the risk for LBW; however, supplementation may increase birthweight by ~130 g. Consumption of whole foods such as fruit, vegetables, low-fat dairy, and lean meats throughout pregnancy appears beneficial for appropriate birthweight. Intervention studies with an understanding of optimal dietary patterns may provide promising results for both maternal and perinatal health. Outcomes from these studies will help determine what sort of dietary advice could be promoted to women during pregnancy in order to promote the best health for themselves and their baby.

Identification, prevention and treatment of iron deficiency during the first 1000 days

Iron deficiency is a global problem across the life course, but infants and their mothers are especially vulnerable to both the development and the consequences of iron deficiency. Maternal iron deficiency during pregnancy can predispose offspring to the development of iron deficiency during infancy, with potentially lifelong sequelae. This review explores iron status throughout these "first 1000 days" from pregnancy through two years of age, covering the role of iron and the epidemiology of iron deficiency, as well as its consequences, identification, interventions and remaining research gaps.

Maternal low glycaemic index diet, fat intake and postprandial glucose influences neonatal adiposity--secondary analysis from the ROLO study

BACKGROUND

The in utero environment is known to affect fetal development however many of the mechanisms by which this occurs remain unknown. The aim of this study was to examine the association between maternal dietary macronutrient intake and lifestyle throughout pregnancy and neonatal weight and adiposity.

METHODS

This was an analysis of 542 mother and infant pairs from the ROLO study (Randomised cOntrol trial of LOw glycaemic index diet versus no dietary intervention to prevent recurrence of fetal macrosomia). Food diaries as well as food frequency and lifestyle and physical activity questionnaires were completed during pregnancy. Maternal anthropometry was measured throughout pregnancy and neonatal anthropometry was measured at birth.

RESULTS

Multiple linear regression analysis revealed the main maternal factor associated with increased birth weight was greater gestational weight gain R2adj 23.3% (F = 11.547, p < 0.001). The main maternal factor associated with increased birth length was non-smoking status R2adj 27.8% (F = 6.193, p < 0.001). Neonatal central adiposity (determined using waist:length ratio) was negatively associated with maternal age, and positively associated with the following parameters: smoking status, maternal pre-pregnancy arm circumference, percentage energy from saturated fat in late pregnancy, postprandial glucose at 28 weeks gestation and membership of the control group with a positive trend towards association with trimester 2 glycaemic load R2adj 38.1% (F = 8.000, p < 0.001).

CONCLUSIONS

Several maternal diet and lifestyle factors were associated with neonatal anthropometry . Low glycaemic index dietary intervention in pregnancy was found to have a beneficial effect on neonatal central adiposity. Additionally, central adiposity was positively associated with maternal dietary fat intake and postprandial glucose highlighting the important role of healthy diet in pregnancy in promoting normal neonatal adiposity.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN54392969.

Gestational iron deficiency differentially alters the structure and function of white and gray matter brain regions of developing rats

Gestational iron deficiency (ID) has been associated with a wide variety of central nervous system (CNS) impairments in developing offspring. However, a focus on singular regions has impeded an understanding of the CNS-wide effects of this micronutrient deficiency. Because the developing brain requires iron during specific phases of growth in a region-specific manner, we hypothesized that maternal iron deprivation would lead to region-specific impairments in the CNS of offspring. Female rats were fed an iron control (Fe+) or iron-deficient (Fe-) diet containing 240 or 6 μg/g iron during gestation and lactation. The corpus callosum (CC), hippocampus, and cortex of the offspring were analyzed at postnatal day 21 (P21) and/or P40 using structural and functional measures. In the CC at P40, ID was associated with reduced peak amplitudes of compound action potentials specific to myelinated axons, in which diameters were reduced by ∼20% compared with Fe+ controls. In the hippocampus, ID was associated with a 25% reduction in basal dendritic length of pyramidal neurons at P21, whereas branching complexity was unaffected. We also identified a shift toward increased proximal branching of apical dendrites in ID without an effect on overall length compared with Fe+ controls. ID also affected cortical neurons, but unlike the hippocampus, both apical and basal dendrites displayed a uniform decrease in branching complexity, with no significant effect on overall length. These deficits culminated in significantly poorer performance of P40 Fe- offspring in the novel object recognition task. Collectively, these results demonstrate that non-anemic gestational ID has a significant and region-specific impact on neuronal development and may provide a framework for understanding and recognizing the presentation of clinical symptoms of ID.

Hypoxia-inducible factor-1α (HIF-1α) expression in placentae of women with iron deficiency anemia and β-thalassemia trait

OBJECTIVE

To investigate hypoxia-inducible factor-1α (HIF-1α) expression in placentae of women with iron-deficiency anemia and β-thalassemia trait and to correlate the results with hematological parameters as well as with parameters associated with the outcome of pregnancy.

METHODS

About 126 women who delivered in the Larissa University Hospital were divided in three groups: iron-deficiency anemia (n = 39), β-thalassemia trait carriers (n = 53) and control group (n = 34). HIF-1α expression was assessed with immunochemical assays and statistical analysis was performed with chi-squared test and ANOVA.

RESULTS

HIF-1α immunostaining was intense in the two groups of anemia. A statistically significant association was found between HIF-1α immunoreactivity and hematocrit (p < 0.001), hemoglobin (p < 0.001), MCV (p < 0.001), transferrin (p < 0.001) and its receptors (p = 0.040), whereas no significant correlations were observed between HIF-1α, iron serum levels (p = 0.256) and ferritin (p = 0.232). We found no association between HIF-1α and birthweight (p = 0.256), placental weight (p = 0.870) and Apgar score at 1' (p = 0.210) and 5' (p = 0.400).

CONCLUSIONS

HIF-1α expression is affected by anemia, although this factor has no important direct effect on the perinatal outcome.

Perinatal iron deficiency and neurocognitive development

Iron deficiency is the most common form of nutrient deficiency worldwide. It is highly prevalent due to the limited availability of high quality food in developing countries and poor dietary habits in industrialized countries. According to the World Health Organization, it affects nearly 2 billion people and up to 50% of women who are pregnant. Maternal anemia during pregnancy is especially burdensome to healthy neurodevelopment in the fetus because iron is needed for proper neurogenesis, development, and myelination. Maternal anemia also increases the risk of low birth weight, either due to premature birth or fetal growth restriction, which is associated with delayed neurocognitive development and even psychiatric illness. As rapid neurodevelopment continues after birth infants that received sufficient iron in utero, but that receive a low iron diet after 6 months of age, also show deficits in neurocognitive development, including impairments in learning and memory. Unfortunately, the neurocognitive complications of iron deficiency during critical pre- and postnatal periods of brain development are difficult to remedy, persisting into adulthood. Thus, preventing iron deficiency in the pre- and postnatal periods is critical as is devising new means to recapture cognitive function in individuals who experienced early iron deficiency. This review will discuss the prevalence of pre- and postnatal iron deficiency, the mechanism, and effects of iron deficiency on brain and cognitive development.

Anaemia, prenatal iron use, and risk of adverse pregnancy outcomes: systematic review and meta-analysis

OBJECTIVES

To summarise evidence on the associations of maternal anaemia and prenatal iron use with maternal haematological and adverse pregnancy outcomes; and to evaluate potential exposure-response relations of dose of iron, duration of use, and haemoglobin concentration in prenatal period with pregnancy outcomes.

DESIGN

Systematic review and meta-analysis

DATA SOURCES

Searches of PubMed and Embase for studies published up to May 2012 and references of review articles.

STUDY SELECTION CRITERIA

Randomised trials of prenatal iron use and prospective cohort studies of prenatal anaemia; cross sectional and case-control studies were excluded.

RESULTS

48 randomised trials (17 793 women) and 44 cohort studies (1 851 682 women) were included. Iron use increased maternal mean haemoglobin concentration by 4.59 (95% confidence interval 3.72 to 5.46) g/L compared with controls and significantly reduced the risk of anaemia (relative risk 0.50, 0.42 to 0.59), iron deficiency (0.59, 0.46 to 0.79), iron deficiency anaemia (0.40, 0.26 to 0.60), and low birth weight (0.81, 0.71 to 0.93). The effect of iron on preterm birth was not significant (relative risk 0.84, 0.68 to 1.03). Analysis of cohort studies showed a significantly higher risk of low birth weight (adjusted odds ratio 1.29, 1.09 to 1.53) and preterm birth (1.21, 1.13 to 1.30) with anaemia in the first or second trimester. Exposure-response analysis indicated that for every 10 mg increase in iron dose/day, up to 66 mg/day, the relative risk of maternal anaemia was 0.88 (0.84 to 0.92) (P for linear trend<0.001). Birth weight increased by 15.1 (6.0 to 24.2) g (P for linear trend=0.005) and risk of low birth weight decreased by 3% (relative risk 0.97, 0.95 to 0.98) for every 10 mg increase in dose/day (P for linear trend<0.001). Duration of use was not significantly associated with the outcomes after adjustment for dose. Furthermore, for each 1 g/L increase in mean haemoglobin, birth weight increased by 14.0 (6.8 to 21.8) g (P for linear trend=0.002); however, mean haemoglobin was not associated with the risk of low birth weight and preterm birth. No evidence of a significant effect on duration of gestation, small for gestational age births, and birth length was noted.

CONCLUSIONS

Daily prenatal use of iron substantially improved birth weight in a linear dose-response fashion, probably leading to a reduction in risk of low birth weight. An improvement in prenatal mean haemoglobin concentration linearly increased birth weight.

Prevalence of iron deficiency states and risk of haemoconcentration during pregnancy according to initial iron stores and iron supplementation

OBJECTIVE

To describe the prevalence of iron depletion (ID), iron-deficiency anaemia (IDA) and risk of haemoconcentration during pregnancy and at delivery and to assess the influence of initial Fe stores and Fe supplementation on that prevalence.

DESIGN

Longitudinal study.

SETTING

Hospital Universitari Sant Joan de Reus (Catalonia, Spain).

SUBJECTS

Two hundred and eighty-five pregnant women. Serum ferritin and Hb were measured in the first, second and third trimesters and at delivery. Women were classified according to initial Fe stores as ID or no ID (serum ferritin $12mg/l) and according to Fe supplement use as supplemented or nonsupplemented.

RESULTS

Initial ID was 16.2%. At delivery, 45.7% had ID, 13.5% IDA and 13.3% had risk of haemoconcentration. Initial ID and non-supplemented groups had significantly higher prevalences of ID and IDA and lower risk of haemoconcentration at delivery than the other groups. In the multiple logistic models, no initial ID and Fe supplementation exerted a protective effect against ID at delivery (adjusted OR50.28; 95% CI 0.13, 0.58 and adjusted OR50.39; 95% CI 0.22, 0.69, respectively). Moderate Fe supplementation did not seem to clearly prevent IDA (adjusted OR50.91; 95% CI 0.42, 1.96) or to enhance the haemoconcentration (adjusted OR51.42; 95% CI 0.58, 3.50).

CONCLUSIONS

The prevalence of ID and IDA was high in late pregnancy in healthy pregnant women, particularly in those with initial ID and/or those not taking supplements. Starting pregnancy with no ID and/or taking moderate Fe supplementation decreased the likelihood of ID at delivery. The risk of haemoconcentration was high at delivery, but did not seem to be promoted by Fe supplementation. Further research is necessary to determine the most appropriate nutritional advice for pregnant women.

Pregnancy and iron homeostasis: an update

It has been nearly 15 years since the first review on pregnancy and iron deficiency was published in Nutrition Reviews. Many unresolved issues raised in that seminal review have been addressed. New proteins involved in nonheme and heme iron transport have been identified in the enterocyte, and information on the roles of these proteins in the placenta is evolving. The systemic iron regulatory hormone, hepcidin, has since been identified as a key regulator of iron homeostasis. Additional data on the efficacy and consequences of prenatal iron supplementation are available. Emerging data on developmental changes in iron absorption across early infancy have further emphasized the need to ensure that the iron endowment of the neonate at birth is optimal. This is especially important, given growing evidence linking neonatal iron status with subsequent cognitive and neurobehavioral outcomes. Along with the many advances, new questions and gaps in knowledge have been identified. This review summarizes new data on maternal iron utilization across pregnancy as it impacts the pregnant woman and the iron status of the neonate at birth.

Is intravenous iron sucrose the treatment of choice for pregnant anemic women?

Anemia during pregnancy remains an important public health problem in developing countries like India. Anemia is the direct cause of 12-15% of maternal deaths. Iron deficiency is the commonest cause for anemia in the Indian subcontinent. Several preventive and therapeutic approaches are in practice. The available routes of iron supplementation are oral and intravenous. In spite of oral iron being least invasive, cheap and safe, the ineffectiveness of oral iron due to dietary inhibitors and poor compliance are well known. Intravenous iron sucrose can be a promising therapy for moderate to severely anemic pregnant women and has been in practice for quite some time in private and public health practices. In this article, we report the current evidence on the safety and efficacy of intravenous iron sucrose in anemic pregnant women on hematological and clinical outcomes. Though the evidence on its efficacy in improving hemoglobin and serum ferritin is convincing, its effect on maternal and fetal outcomes are unclear. This is primarily due to lack of well-designed and larger studies powered to detect difference in clinical outcomes. Hence, there is a need to gather evidence from a well-designed large randomized clinical trial conducted in a developing country. The results of such a study would feed into the national policy and would form the basis to frame guidelines for management of anemia in developing countries.

Public health interventions, barriers, and opportunities for improving maternal nutrition in Northeast Nigeria

BACKGROUND

Efficacious strategies to improve maternal nutrition and subsequent maternal, neonatal, and child health exist, but their utilization and application at scale is limited.

OBJECTIVE

This study explored the gaps, barriers, and opportunities for maternal nutrition policy and programming in Nigeria, a country with a disproportionate share of the global burden of maternal and child mortality

METHODS

Research was conducted in three phases in four Local Government Authorities in Taraba State. Phase 1 consisted of a desk review of policies, programs, and sociodemographic and health indicators pertinent to maternal nutrition. In-depth interviews were conducted with key informants in state and local ministries of health as well as international nongovernmental organizations and community- and faith-based organizations. Phase 2 utilized in-depth interviews and focus group discussions with community leaders, health promoters, and mothers. Phase 3 consisted of key informant interviews with federal policy and program leaders in government ministries and nongovernmental organizations.

RESULTS

Nutrition, especially maternal nutrition, is not prioritized and is poorly funded in both the governmental and the nongovernmental systems. Perceived weak advocacy for nutrition and its role in economic development and the lack of coordination among governmental and nongovernmental actors were said to contribute to low prioritization. Dependence on health facilities as the primary platform for delivering maternal nutrition is problematic, given severe resource constraints and perceived community barriers, including cost, distance, and poor quality of care.

CONCLUSIONS

Advocacy for maternal nutrition that improves understanding of its consequences for health and economic development could hasten prioritization, coordination, and investment in maternal nutrition at the national, state, and local levels. Innovative, multisectoral strategies that move beyond facility-based platforms are needed to reduce the burden of maternal undernutrition in Northeast Nigeria.

[Hungarian Diet and Nutritional Status Survey -- the OTAP2009 study. V. Intake of microelements in the Hungarian population]

For a healthy status the adequate intake of microelements is vital.

AIM AND METHOD

The Hungarian Diet and Nutritional Status Survey - joining to the European Health Interview Survey - studied the dietary habits of the Hungarian population. The present paper demonstrates the microelement intake.

RESULTS

While the intake of iron, copper and zinc was sufficient in males, it was deficient in females according to the Hungarian recommendations. Especially women in their reproductive age ingested iron below the recommendation, thus representing a health risk. In comparison to earlier Hungarian data, zinc and chromium intake decreased unfavorable.

CONCLUSIONS

Since in Hungary the consumption of the whole grain products with high trace element content is traditionally low, as also reflected in the present study, it would be desirable to increase the contribution of these foods in the diet in order to enhance the intake of microelements.