Inadequate iron stores in early term neonates

Effect of Maternal Nutritional Status and Mode of Delivery on Zinc and Iron Stores at Birth

Zinc and iron deficiencies among infants aged under 6 months may be related with nutrient store at birth. This study aimed to investigate the association between zinc and iron stores at birth with maternal nutritional status and intakes during pregnancy. 117 pregnant women were enrolled at the end of second trimester and followed until delivery. Clinical data during pregnancy, including pre-pregnancy body mass index (BMI) and at parturition were collected from medical record. Zinc and iron intakes were estimated from a food frequency questionnaire. Serum zinc and ferritin were determined in maternal blood at enrollment and cord blood. Mean cord blood zinc and ferritin were 10.8 ± 2.6 µmol/L and 176 ± 75.6 µg/L, respectively. Cord blood zinc was associated with pre-pregnancy BMI (adj. ß 0.150; p = 0.023) and serum zinc (adj. ß 0.115; p = 0.023). Cord blood ferritin was associated with pre-pregnancy BMI (adj. ß -5.231; p = 0.009). Cord blood zinc and ferritin were significantly higher among those having vaginal delivery compared to cesarean delivery (adj. ß 1.376; p = 0.007 and 32.959; p = 0.028, respectively). Maternal nutritional status and mode of delivery were significantly associated with zinc and iron stores at birth. Nutrition during preconception and pregnancy should be ensured to build adequate stores of nutrients for infants.

Iron Content of Commercially Available Infant and Toddler Foods in the United States, 2015

OBJECTIVES

To describe the iron content of commercially available infant and toddler foods.

METHODS

Nutrition Facts label data were used from a 2015 database of 1037 commercial infant and toddler food and drink products. Products were grouped into food categories on the basis of name, ingredients, target age, and reference amounts customarily consumed (RACC). Mean and median iron content per 100 g and per RACC were calculated. The proportion of products considered good and excellent sources of iron were determined on the basis of percent daily value (% DV) thresholds.

RESULTS

Among products marketed for infants (aged 4-12 months), infant cereals had the highest mean (6.19 mg iron per RACC; 41.25 iron mg per 100 g) iron content. Among products marketed for toddlers (aged 12-36 months), vegetable-based mixtures or meals contained the highest mean iron in mg per RACC (mean: 2.97 mg) and dry, grain-based desserts had the highest mean iron in mg per 100 g (mean: 6.45 mg). Juice and drink products had the lowest mean iron contents in both infant and toddler products.

CONCLUSIONS

Most commercially available infant cereals are considered to be an excellent source of iron, likely from fortification, but wide variability was observed in iron content by food category. Products that are considered good or excellent sources of iron (≥10% DV) can help consumers identify products with higher iron content, such as infant cereals or toddler vegetable-based mixtures/meals.

Maternal Prenatal Psychosocial Stress and Prepregnancy BMI Associations with Fetal Iron Status

BACKGROUND

Iron accrued in utero is critical for fetal and infant neurocognitive development. Psychosocial stress and obesity can each suppress fetal iron accrual. Their combined effects and differences by fetal sex are not known. In an observational pregnancy cohort study in Mexico City, we investigated associations of maternal prenatal life stressors, psychological dysfunction, and prepregnancy BMI with fetal iron status at delivery.

OBJECTIVES

We hypothesized that greater maternal prenatal psychosocial stress and prepregnancy overweight and obesity are associated with lower cord blood ferritin and hemoglobin (Hb), with stronger associations in boys than girls.

METHODS

Psychosocial stress in multiple domains of life stress (negative life events, perceived stress, exposure to violence) and psychological dysfunction symptoms (depression, generalized anxiety, and pregnancy-specific anxiety) were assessed with validated questionnaires during pregnancy. Prepregnancy BMI was predicted with a validated equation and categorized as normal/overweight/obese. Cord blood ferritin and Hb associations with prenatal psychosocial stress and BMI were modeled in multivariable linear regressions adjusted for maternal age, socioeconomic status, child sex, and prenatal iron supplementation. Interactions with child sex and 3-way stress-overweight/obesity-sex interactions were tested with product terms and likelihood ratio tests.

RESULTS

In 493 dyads, median (IQR) cord blood ferritin and Hb concentrations were 185 µg/L (126-263 g/dL) and 16 g/dL (14.7-17.1 g/dL), respectively. Ferritin was lower in infants of mothers with higher prenatal perceived stress (-23%; 95% CI: -35%, -9%), violence exposure (-28%; 95% CI: -42%, -12%), anxiety symptoms (-16%; 95% CI: -27%, -4%), and obesity (-17%; 95% CI: -31%, 0.2%). Interaction models suggested sex differences and synergism between maternal stress and overweight/obesity. No associations were observed between stress or BMI and Hb.

CONCLUSIONS

Multiple prenatal psychosocial stressors and excess prepregnancy BMI were each inversely associated with fetal iron status at birth. Pregnancies and infants at elevated risk of impaired fetal iron accrual may be identifiable according to observed synergism between maternal stress and obesity and differential associations with fetal iron status by infant sex.