Maternal iron intake during pregnancy and the risk of small for gestational age

Serum Ferritin Combined with Glycated Hemoglobin for Early Prediction of Gestational Diabetes Mellitus: A Retrospective Cohort Study

OBJECTIVE

To investigate the value of serum ferritin (SF) in conjunction with glycated hemoglobin (HbA1c) for the early prediction of gestational diabetes mellitus (GDM) and to provide insights that could enhance health care standards for women and newborns.

METHODS

A retrospective cohort study was conducted involving 650 pregnant women who received regular prenatal check-ups at our institution from January 2019 to April 2024. Participants were categorized into four groups based on their SF concentration quartiles during the 11th to 13th weeks of gestation. Logistic regression analyses were conducted to assess the predictive value of early GDM risk factors, with the lowest quartile group serving as a reference.

RESULTS

The incidence rate of GDM rose progressively with increasing SF concentrations at 11-13 weeks of gestation, with rates of 18.79%, 21.25%, 24.38%, and 25.45% respectively. Notably, the incidence rate in the highest quartile group (quartile 4) was significantly higher compared to the lowest (quartile 1), with an odds ratio of 1.48 and a 95% confidence interval of 1.12 to 1.93. Additionally, the predictive model incorporating both SF concentration and HbA1c (Model 2) outperformed the model with SF alone (Model 1), indicating a heightened predictive accuracy for GDM when these two biomarkers are used in combination.

CONCLUSION

The findings of this study highlight the potential utility of SF and HbA1c as early predictors of GDM risk, especially when employed in combination.

Association between dietary inflammation index with anemia in Americans: a cross-sectional study with U.S. National health and nutrition examination survey

OBJECTIVES

Dietary inflammatory index (DII) is utilized to determine the inflammatory effects of nutrients and foods on various diseases. Inflammation is a potential risk factor for anemia. We hypothesize that pro-inflammatory diets boost the incidence of anemia, as indicated by high DII.

METHODS

41, 360 Americans were included in this study from the U.S. National Health and Nutrition Survey (NHANES) from 2003-2018. Multivariable logistic regression models were employed to examine the association between DII and anemia.

RESULTS

After adjustment for all the covariates, the odds ratios (ORs) (95% CI) between the risk of anemia and DII across tertile 3 were 1.2556 (95% CI 1.0621, 1.4843; P = 0.0077), and the trend test was statistically significant (P for trend = 0.009). Furthermore, in the subgroup analysis stratified by gender. The ORs (95% CI) between the risk of anemia and DII across tertile 2 and 3 were 1.8071 (95% CI 1.1754, 2.7783; P = 0.0070) and 2.1591 (95% CI 1.4009, 3.3278; P = 0.0005) in men after multivariable adjustment. However, in women, this association was only significantly different (P < 0.05) across tertile 3 in the crude model. In the subgroup analysis stratified by race, this association was significant (P < 0.05) between the risk of anemia and DII for Non-Hispanic Whites/Blacks after adjustment.

DISCUSSION

Together, anemia was significantly associated with DII using logistic regression. In stratified analyses, higher DII scores were linked to an increased incidence of anemia in men, while no association was found in women after adjustment. Additionally, anemia may be associated with greater pro-inflammatory diets in Non-Hispanic Whites/Blacks.

CONCLUSION

In the present study, we evaluate the potential relationship between DII and anemia using data from NHANES. This cross-sectional study confirmed the hypothesis that the higher DII was significantly associated with a higher risk of anemia in the U.S. population.

Maternal iron nutrition during pregnancy and fetal intrauterine growth

BACKGROUND

Iron is critical for maternal and fetal health; however, the effect of iron nutrition on fetal intrauterine growth remains unclear. This study aimed to investigate the associations of maternal iron nutrition during pregnancy with fetal intrauterine growth parameters among the Chinese population.

METHODS

This retrospective birth cohort study included 482 pregnant women. Maternal information was collected by standard questionnaires. Maternal concentrations of serum ferritin and hemoglobin were detected. Fetal ultrasound examinations in the second and third trimesters were conducted. Quantile regression or linear regression models were applied to assess the associations.

RESULTS

Participants took iron supplementation in early, mid, and late pregnancy accounted for 19.1%, 40.3%, and 37.8%, respectively. Iron supplementation in the first and second trimesters and total iron intake in pregnancy were positively associated with fetal intrauterine growth parameters at some percentiles. Compared with those without iron supplementation in the second trimester, women with iron supplementation in the second trimester had 0.37 (95%CI = 0.24-0.49), 0.37 (95%CI = 0.26-0.48), 0.15 (95%CI = 0.04-0.26), and 0.52 (95%CI = 0.42-0.61) higher z-scores in fetal biparietal diameter, femur length, abdominal circumference, and estimated fetal weight at the 50th percentile in the second trimester, respectively. Maternal serum ferritin and hemoglobin concentrations in the first and second trimesters were positively correlated with several fetal growth parameters.

CONCLUSIONS

Fetal intrauterine growth may benefit from maternal iron nutrition in the first and second trimesters.

Screening and Supplementation for Iron Deficiency and Iron Deficiency Anemia During Pregnancy: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance

In 2015 the US Preventive Services Task Force (USPSTF) found insufficient evidence to assess the balance of benefits and harms of routine screening and supplementation for iron deficiency anemia during pregnancy.

Objective

To update the 2015 review on screening for iron deficiency anemia, in addition to iron deficiency during pregnancy, to inform the USPSTF.

Data Sources

Ovid MEDLINE and Cochrane databases through May 24, 2023; surveillance through May 24, 2024.

Study Selection

Randomized clinical trials of iron supplementation, screening effectiveness, treatment, and harms; observational studies of screening.

Data Extraction and Synthesis

Dual review of abstracts, full-text articles, study quality, and data abstraction. Data were pooled using a random-effects model.

Main Outcomes and Measures

Maternal and infant clinical outcomes, hematologic indices, and harms.

Results

Seventeen trials (N = 24 023) on maternal iron supplementation were included. Iron supplementation was associated with decreased risk of maternal iron deficiency anemia at term (4 trials, n = 2230; 8.6% vs 19.8%; relative risk, 0.40 [95% CI, 0.26-0.61]; I2 = 20.5%) and maternal iron deficiency at term (6 trials, n = 2361; 46% vs 70%; relative risk, 0.47 [95% CI, 0.33-0.67]; I2 = 81.9%) compared with placebo or no iron supplement. There were no statistically significant differences in maternal quality of life, rates of gestational diabetes, maternal hemorrhage, hypertensive disorders of pregnancy, cesarean delivery, preterm birth, infant low birth weight, or infants small for gestational age for maternal iron supplementation compared with placebo or no supplementation. Harms of iron supplementation included transient gastrointestinal adverse effects. No studies evaluated the benefits or harms of screening for iron deficiency or iron deficiency anemia during pregnancy. Data on the association between iron status and health outcomes, such as hypertensive disorders of pregnancy and preterm birth, were very limited.

Conclusions and Relevance

Routine prenatal iron supplementation reduces the incidence of iron deficiency and iron deficiency anemia during pregnancy, but evidence on health outcomes is limited or indicates no benefit. No studies addressed screening for iron deficiency or iron deficiency anemia during pregnancy. Research is needed to understand the association between changes in maternal iron status measures and health outcomes.

Dietary management of gestational diabetes: A review

Gestational diabetes mellitus (GDM) is a common condition in pregnant women that can affect the health of both the mother and the fetus. A healthy diet reduces the risk of GDM, while on the contrary, an unhealthy diet can increase the risk of developing GDM. Dietary interventions remain an important way to control GDM at this time. However, real-life diets are complex and varied, and the effect of these diets on gestational diabetes is unknown. This article summarizes research related to dietary control of GDM. Hopefully, this will help with dietary interventions for people with GDM.

Association of a pro-inflammatory diet and gestational diabetes mellitus with maternal anemia and hemoglobin levels during pregnancy: a prospective observational case-control study

Anemia is prevalent in pregnant women, and the causes include inadequate diet, increased demand for iron, and inflammation. We hypothesized that gestational diabetes mellitus (GDM) and hepcidin-related gene polymorphisms may contribute to maternal anemia and that an anti-inflammatory diet can alleviate this negative effect. The aim of this study was to investigate the association of an inflammatory diet, GDM, and single nucleotide polymorphisms (SNPs) in hepcidin-related genes, which are key regulators of iron, with maternal anemia. This was a secondary data analysis of a prospective prenatal diet and pregnancy outcome study in Japan. The Energy-Adjusted Dietary Inflammatory Index was calculated using a brief self-administered diet history questionnaire. We analyzed 121 SNPs in 4 genes: TMPRS6 (43 SNPs), TF (39 SNPs), HFE (15 SNPs), and MTHFR (24 SNPs). Multivariate regression analysis was conducted to determine the association between the first variable and maternal anemia. The prevalence of anemia in first, second, and third trimesters were 5.4%, 34.9%, and 45.8%, respectively. The pregnant women with GDM had a significantly higher incidence of moderate anemia than those without GDM (40.0% vs. 11.4%, P = .029). In multivariate regression analysis, Energy-adjusted Dietary Inflammatory Index (β = -0.057, P = .011) and GDM (β = -0.657, P = .037) were significantly associated with hemoglobin levels during the third trimester. Using Stata's qtlsnp command, TMPRSS6 rs2235321 was found to be associated with hemoglobin levels during the third trimester. These results indicate that inflammatory diets, GDM, and TMPRSS6 rs2235321 polymorphism are associated with maternal anemia. This result suggests that a pro-inflammatory diet and GDM are associated with maternal anemia.

Correlation between high serum ferritin levels and adverse pregnancy outcomes in women with gestational diabetes mellitus

Aims

To explore the association between higher serum ferritin (SF) levels in mid-pregnancy and adverse pregnancy outcomes in gestational diabetes mellitus (GDM) pregnancies, then develop a predictive cut-off value that might effectively predict the risk of adverse pregnancy outcomes in future clinical.

Methods

The study involved 201 pregnant women with GDM. 201 gestational age and parity matched normoglycemic pregnant women were taken as control group. The differences in clinical data were compared by the Mann-Whitney U test and Chi-square tests. Multivariate logistic regression was used to determine the relationship between SF and GDM-relate adverse pregnancy outcomes. The predicted value of SF level was determined through receiver operating characteristic (ROC) curve analysis.

Results

SF level was significantly higher in women with GDM [16.10 (27.30-9.50) (ng/mL) vs. 12.04 (18.11-7.06) (ng/mL), (p < 0.001)]. Meanwhile, higher levels of SF were also discovered in GDM women with preeclampsia and neonatal hypoglycemia and respiratory distress (all p < 0.05). In the adjusted model, a positive association was shown between SF and preeclampsia [adjusted odds ratio (AOR) = 1.032, 95%CI = 1.004-1.060, p = 0.024], neonatal hypoglycemia [adjusted odds ratio (AOR) = 1.047, 95%CI = 1.022-1.072, p < 0.001] and respiratory distress outcomes (AOR = 1.034, 95%CI = 1.011-1.058, p = 0.004) respectively. The area under ROC curve (AUC) for prediction of preeclampsia by SF combined with serum calcium, age, pre-pregnancy BMI and gestational weight gain (GWG) was 0.658 (95% CI = 50.8-80.8%, p = 0.028) with the cut-off value of 24.45 ng/mL, and the sensitivity and specificity were 58.8.0% and 64.3%, respectively. To predict neonatal hypoglycemia, the clinical point value of SF was 27.43 ng/mL with AUC was 0.800, sensitivity and specificity was 90.5% and 68.0% respectively. Predicting neonatal respiratory distress, the AUC value of the SF level was 0.730, with a cut-off value of 27.37 ng/mL and the sensitivity and specificity were 52.0% and 86.5%, respectively.

Conclusions

Higher level of SF in mid-pregnancy was significantly associated with the risk of GDM and GDM-relate adverse pregnancy outcomes. Moreover, SF levels have moderate clinical value in predicting the adverse outcomes of maternal preeclampsia, neonatal hypoglycemia and respiratory distress.

Impact of iron supplementation on gestational diabetes mellitus: A literature review

Gestational diabetes mellitus (GDM) is a common complication of pregnancy, affecting 14% of pregnancies worldwide, and the prevention of pathological hyperglycaemia during pregnancy is meaningful for global public health. The role of iron supplementation in the progression of GDM has been of significant interest in recent years. Iron is a micronutrient that is vital during pregnancy; however, given the toxic properties of excess iron, it is probable that prophylactic iron supplementation will increase the risk of adverse pregnancy outcomes, including GDM. It is critical to clarify the effect of iron supplementation on the risk of GDM. Therefore, in this review, we comprehensively assess the role of iron in pregnancy. This review aimed to analyse the necessity of iron supplementation and maintenance of iron homeostasis during pregnancy, particularly reviewing the role and function of iron in beta cells and examining the mechanisms of excess iron contributing to the pathogenesis of GDM. Moreover, we aimed to discuss the association of haemoglobin and ferritin with GDM and identify priority areas for research.

Association of maternity formula supplementation during pregnancy with small for gestational age birth in Chinese newborns

OBJECTIVES

This study aimed to explore the association between maternity formula supplementation and small for gestational age (SGA) status in Chinese newborns.

METHODS

Data were from a population-based cross-sectional survey conducted in Shaanxi, Northwest China between August and December 2013. A total of 27 780 women pregnant with singletons and 356 with twins were included in this survey. Information on use of maternity formulas fortified with vitamins, folic acid, pantothenic acid, calcium, iron, zinc, and docosahexaenoic acid (DHA) was collected. SGA was defined as birthweight <10th percentile of fetal growth. Generalized linear models and estimating equation models were used to estimate crude odds ratios (ORs) or adjusted ORs with 95% confidence intervals (CIs) for SGA.

RESULTS

The rate of maternity formula supplementation during the entire pregnancy was 13.0% in the overall population. There was no significant association between maternal formula supplementation during pregnancy and the risk of total SGA birth (OR: 1.00; 95% CI, 0.90-1.11; P = 0.950). However, maternity formula supplementation during pregnancy was related to a lower risk of SGA for twins (OR: 0.49; 95% CI, 0.31-0.80; P = 0.004), twin A (OR: 0.50; 95% CI, 0.25-0.98; P = 0.045), and twin B (OR: 0.48; 95% CI, 0.25-0.95; P = 0.034). Furthermore, maternity formula supplementation during the first trimester was inversely associated with the risk of SGA birth of twins (OR: 0.32; 95% CI, 0.15-0.65; P = 0.002).

CONCLUSIONS

No significant association was observed between maternity formula supplementation and total SGA birth. However, women supplemented with maternal formula during pregnancy, especially during the first trimester, may have a reduced risk of SGA birth of twins.

Longitudinal Nutritional Intakes in Italian Pregnant Women in Comparison with National Nutritional Guidelines

BACKGROUND

Nutritional quality during pregnancy is crucial for mother and child health and their short/long-term outcomes. The aim of this study is to evaluate the adherence to nutritional recommendations in Italy during the three pregnancy trimesters in Normal Weight (NW) and Over Weight (OW) women.

METHODS

Data from a multicenter randomized controlled trial included 176 women (NW = 133; OW = 43) with healthy singleton pregnancies enrolled within 13 + 6 weeks of gestation. Dietary intake was assessed every trimester by a Food Frequency Questionnaire.

RESULTS

OW and NW had similar gestational weight gain. However, as Institute of Medicine (IOM) recommend lower gestational weight gain (GWG) for OW, they exceeded the suggested range. In both groups, caloric intake during the three trimesters never met recommendations. Protein intake in first and second trimester was higher than recommendations, as was sugars percentage. Dietary fiber intake was lower in OW. Polyunsaturated fatty acids, calcium, iron and folic acid requirements were never satisfied, while sodium intake exceeded recommendations.

CONCLUSIONS

NW and OW women in Italy do not adhere to nutritional recommendations during pregnancy, with lower caloric intake, protein and sugars excess and inadequacies in micronutrients intake. Pregnant women in Italy should be provided with an adequate counseling and educational intervention as well as supplementation when indicated.

Nutrition and Brain Development

All nutrients are essential for brain development, but pre-clinical and clinical studies have revealed sensitive periods of brain development during which key nutrients are critical. An understanding of these nutrient-specific sensitive periods and the accompanying brain regions or processes that are developing can guide effective nutrition interventions as well as the choice of meaningful circuit-specific neurobehavioral tests to best determine outcome. For several nutrients including protein, iron, iodine, and choline, pre-clinical and clinical studies align to identify the same sensitive periods, while for other nutrients, such as long-chain polyunsaturated fatty acids, zinc, and vitamin D, pre-clinical models demonstrate benefit which is not consistently shown in clinical studies. This discordance of pre-clinical and clinical results is potentially due to key differences in the timing, dose, and/or duration of the nutritional intervention as well as the pre-existing nutritional status of the target population. In general, however, the optimal window of success for nutritional intervention to best support brain development is in late fetal and early postnatal life. Lack of essential nutrients during these times can lead to long-lasting dysfunction and significant loss of developmental potential.

Association between maternal plasma ferritin concentration, iron supplement use, and the risk of gestational diabetes: a prospective cohort study

BACKGROUND

The association between iron supplementation and gestational diabetes mellitus (GDM) is still inconclusive, and this association has not been extensively studied in relation to plasma ferritin in the early second trimester.

OBJECTIVES

We aimed to prospectively examine the independent and combined associations of plasma ferritin concentrations and iron supplement use with GDM.

METHODS

We studied 2117 women from the Tongji Maternal and Child Health Cohort in Wuhan, China. Plasma ferritin around 16 weeks' gestation was measured by ELISA kits and information on iron supplement use was collected by questionnaires. GDM was diagnosed by a 75-g oral-glucose-tolerance test (OGTT) at 24-28 weeks' gestation. A log-Poisson regression model was used to estimate the RR of GDM associated with plasma ferritin and iron supplementation.

RESULTS

The median and IQR of plasma ferritin was 52.1 (29.6-89.9) ng/mL, and 863 (40.8%) participants reported use of iron supplements during the second trimester. A total of 219 (10.3%) participants developed GDM. Adjusted RRs (95% CIs) for GDM across increasing quartiles of plasma ferritin were 1.00 (reference), 2.14 (1.37, 3.34), 2.03 (1.30, 3.19), and 2.72 (1.76, 4.21), respectively. After adjustment, supplemental iron ≥60 mg/d during the second trimester was associated with an increased risk of GDM compared with nonusers (RR: 1.37; 95% CI: 1.02, 1.84).

CONCLUSIONS

Both elevated plasma ferritin concentrations in the early second trimester and use of ≥60 mg/d of supplemental iron during pregnancy are independently associated with increased risk of GDM. Further clinical trials with precision nutrition approaches considering both baseline iron status and supplement use are needed to evaluate the benefits and risks of iron supplementation during pregnancy.

Nutrients that modulate gestational diabetes mellitus: A systematic review of cohort studies Jan 2019-Jan 2020

BACKGROUND

The role of eating habits of pregnant women in the development and treatment of gestational diabetes mellitus (GDM) is well established.

OBJECTIVES

To estimate the contribution of specific nutrients and dietary patterns in the development or privation of GDM in pregnant women.

DATA SOURCES

A systematic review of cohort studies, published between January 2019 and January 2020, of English articles using PubMed, Scopus and Europe PMC databases. Search terms included diabetes, pregnancy, dietary, food, and nutrients.

STUDY SELECTION

Only cohort studies about the association between eating habits before and during pregnancy and the risk of GDM in English were included. The studies used dietary patterns, specific nutrients or records of food intake of the participants using a questionnaire.

DATA EXTRACTION

Two authors independently extracted data from articles-including dietary patterns, food intake, nutrients, number and demographic data of participants, data about pregnancies-using predefined criteria.

RESULTS

In total, 28 cohort studies were organised to examine the correlation between dietary patterns and the prevention of GDM. Studies were conducted in 13 countries and included 3 058 242 participants. Of those, 13 (46%) studies focused on the consumption of vitamins, probiotics, micronutrients, folate, vegetables and fruits. Moreover, seven (25%) studies focused on what is considered to be "unhealthy" eating habits, including prudent and Western dietary patterns. The mediterranean pattern was used in three (11%) studies.

CONCLUSIONS

Ongoing studies support advice to adhere to a healthy balanced diet, with the addition of folic acid and a multi-vitamin suitable for pregnancy. There is new evidence suggesting probiotics and cod-liver oil supplementation may improve glycaemic control and also the important consideration of the psychological influences of eating.

Periconceptional iron supplementation and risk of gestational diabetes mellitus: A prospective cohort study

AIMS

Iron supplementation has been recommended for healthy pregnancy, but concerns have been raised regarding the potential adverse effects. We sought to examine the impact of periconceptional iron supplement use on subsequent gestational diabetes mellitus (GDM) risk.

METHODS

Participants (N = 5101) with information on periconceptional micronutrient supplementation and diagnosis of GDM were involved. Information on iron supplementation and general characteristics were collected at enrollment and follow-up visits. GDM was diagnosed by oral glucose tolerance tests (OGTT) conducted at 24-28 weeks of gestation. Robust Poisson regression model was used to estimate the relative risks (RRs) and 95% confidence intervals (CI) for the effect of iron supplement use on GDM.

RESULTS

10.5% of the participants were diagnosed with GDM and the incidence was significantly higher in users with iron >30 mg/d for more than 3 months (Iron >30-L) than in nonusers. Adjusted RRs (95% CI) were 1.53 (1.21, 1.93) in Iron >30-L group, 1.14 (0.80, 1.61) in users with iron >30 mg/d for<3 months (Iron > 30-S) and 1.15 (0.86, 1.54) in users with iron ≤30 mg/d for any duration (Iron ≤30) respectively, compared to nonusers. This link in Iron >30-L group was even stronger (adjusted RR: 1.70, 95% CI: 1.25, 2.31) when restricting the analysis among primiparous and iron-replete participants without family history of diabetes. There were no significant differences in birth outcomes among groups.

CONCLUSIONS

Periconceptional iron supplementation >30 mg/d for long-term was associated with increased GDM risk. The need and safety of prophylactic iron supplement in iron-replete pregnant women should be reconsidered.

Nutrition in Reproductive Health: Nutritional Conditioning Factors during Pregnancy and Its Impact on Health

During the gestational period, women need to have optimal health to meet fetal requirements for growth and development. Nutrition is one of the most important factors that can ensure a mother`s health and also that of their offspring. The role of maternal diet, before and during pregnancy, has been associated with adverse birth outcomes and a worsening of maternal health. Medical conditions that are closely related to dietary intake and may affect women before or during pregnancy have also been associated with the appearance of pathology in a newborn. To date, several studies have been carried out in order to identify the role of diet as a factor associated with child physiological and psychological health, both in the short and long term. Educating mothers regarding the influence of maternal dietary intake during pregnancy on infants’ health could represent a simple but effective target for public health policies to improve pregnancy nutrition, and therefore help to avoid newborn diseases through the development.

Maternal iron intake during pregnancy and the risk of small for gestational age

Studies of iron and its association with the risk of small for gestational age (SGA) show inconsistent results. Consuming iron supplements during pregnancy is controversial because of possible risks. This study assessed the association between iron intake and the risk of having an SGA newborn and whether iron intake is associated with gestational diabetes. A case-control study of 518 pairs of Spanish women who were pregnant and attending five hospitals was conducted. Groups were matched 1:1 for age (±2 years) and hospital. Cases were women with an SGA newborn at delivery. Controls were women with normal-sized newborns at delivery. Data were gathered on demographic characteristics, socio-economic status, adverse habits (like smoking), and diet. A 137-item food frequency questionnaire was completed. Iron intakes were categorized in quintiles (Q1-Q5). Crude odds ratios (ORs) and adjusted ORs (aORs) with 95% confidence intervals (CIs) were estimated by conditional logistic regression. No significant relationship was found between dietary iron intake and SGA. A protective association was found for women receiving iron supplementation >40 mg/day and SGA versus women not taking supplements (aOR = 0.64, 95% CI [0.42, 0.99]). This association was identified in mothers both with (aOR = 0.57, 95% CI [0.40, 0.81]) and without (aOR = 0.64, 95% CI [0.64, 0.97]) anaemia. In women in the control group without anaemia, iron supplementation >40 mg/day was positively associated with gestational diabetes (aOR = 6.32, 95% CI [1.97, 20.23]). Iron supplementation in pregnancy may prevent SGA independently of existing anaemia but may also increase the risk of gestational diabetes.