Breastfeeding and intelligence of preschool children

Long-term benefits of exclusive human milk diet in small for gestational age neonates: a systematic review of the literature

Evidence about feeding practices' consequences in small for gestational age newborns is not well established because they are less likely to initiate and continue breastfeeding than other newborns. Our aim was to study current knowledge about the benefits of exclusive human milk diet after 2 years of age in small for gestational age newborns. A systematic review of the literature was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline criteria. Pubmed and Scopus were searched for studies published from databases inception until June 2, 2023. Included articles were analysed and synthesised. Risk of bias and level of evidence assessments were performed. They were enrolled small for gestational age newborns fed by breastfeeding, breast milk or donor milk. The systematic review included 9 articles which were related to 4 health domains: neurodevelopment, cardiovascular, somatic growth and bone mineralization and atopy. Extracted data support a beneficial effect of breastfeeding on these outcomes. Better quality of evidence and longer follow-up are needed.

Prenatal exposure to ambient PM2.5 and its chemical constituents and child intelligence quotient at 6 years of age

There are limited studies on the associations between prenatal exposure to constituents of fine particulate matter (PM_2.5) and children's intelligence quotient (IQ). Our study aimed to explore the associations between prenatal PM_2.5 and its six constituents and the IQ levels of 6-year-old children. We included 512 mother-child pairs. We used a satellite-based modelling framework to estimate prenatal PM_2.5 and its six constituents (ammonium, sulfate, nitrate, organic carbon, soil dust, and black carbon). We assessed the children's IQ using the short form of the Wechsler Intelligence Scale. Perceptual Reasoning Index (PRI), Verbal Comprehension Index (VCI), and Full Scale IQ (FSIQ) scores were computed. The multiple informant model (MIM) was applied to explore the trimester specific effects of PM_2.5 and its six constituents' exposure on children's PRI, VCI, and FSIQ. To examine whether the duration of breastfeeding and physical activity (PA) could modify the effects of PM_2.5 on children's IQ, we stratified the analyses according to the duration of breastfeeding (≤6 and >6 months) and time of outdoor activities after school (≤2 and >2 h/week). The first trimester PM_2.5 and its five constituents' exposures were inversely associated with FSIQ [β = -1.34, 95 % confidence interval [CI] (-2.71, 0.04) for PM_2.5] and PRI [β = -2.18, 95 %CI (-3.80, -0.57) for PM_2.5] in children. The associations were magnified among boys and those with less outdoor activities or shorter breastfeeding duration. Our results indicate that prenatal PM_2.5 and several of its main constituents' exposure may disrupt cognitive development in children aged 6 years. More PA and longer breastfeeding duration may alleviate the detrimental effects of prenatal PM_2.5 exposure on children's cognitive function.

Exclusive breastfeeding and developmental and behavioral status in early childhood

Breastfeeding during infancy may have beneficial effects on various developmental outcomes in childhood. In this study, exclusively breastfed infants were randomly assigned to receive complementary foods from the age of 4 months in addition to breast milk (CF, n = 60), or to exclusively breastfeed to 6 months (EBF, n = 59). At 18 months and again at 30–35 months of age, the children were evaluated with the Parent’s Evaluation of Developmental Status questionnaire (PEDS) and the Brigance Screens-II. The parents completed the PEDS questionnaire at both time intervals and the children underwent the Brigance Screens-II at 30–35 months. At 30–35 months, no significant differences were seen in developmental scores from the Brigance screening test (p = 0.82). However, at 30–35 months a smaller percentage of parents in group CF (2%) had concerns about their children’s gross motor development compared to those in group EBF (19%; p = 0.01), which remained significant when adjusted for differences in pre-randomization characteristics (p = 0.03). No sustained effect of a longer duration of exclusive breastfeeding was seen on selected measures of developmental and behavioral status at 18 months, although at 30–35 months, a smaller percentage of parents of children introduced to complementary foods at four months of age expressed concerns about their gross motor development.

Breast milk and cognitive development--the role of confounders: a systematic review

OBJECTIVES

The association between breastfeeding and child cognitive development is conflicted by studies reporting positive and null effects. This relationship may be confounded by factors associated with breastfeeding, specifically maternal socioeconomic class and IQ.

DESIGN

Systematic review of the literature.

SETTING AND PARTICIPANTS

Any prospective or retrospective study, in any language, evaluating the association between breastfeeding and cognitive development using a validated method in healthy term infants, children or adults, was included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Extracted data included the study design, target population and sample size, breastfeeding exposure, cognitive development assessment tool used and participants' age, summary of the results prior to, and following, adjustment for confounders, and all confounders adjusted for. Study quality was assessed as well.

RESULTS

84 studies met our inclusion criteria (34 rated as high quality, 26 moderate and 24 low quality). Critical assessment of accepted studies revealed the following associations: 21 null, 28 positive, 18 null after adjusting for confounders and 17 positive-diminished after adjusting for confounders. Directionality of effect did not correlate with study quality; however, studies showing a decreased effect after multivariate analysis were of superior quality compared with other study groupings (14/17 high quality, 82%). Further, studies that showed null or diminished effect after multivariate analysis corrected for significantly more confounders (7.7±3.4) as compared with those that found no change following adjustment (5.6±4.5, p=0.04). The majority of included studies were carried out during childhood (75%) and set in high-income countries (85.5%).

CONCLUSIONS

Much of the reported effect of breastfeeding on child neurodevelopment is due to confounding. It is unlikely that additional work will change the current synthesis. Future studies should attempt to rigorously control for all important confounders. Alternatively, study designs using sibling cohorts discordant for breastfeeding may yield more robust conclusions.

Developmental status of 1-year-old infants fed breast milk, cow's milk formula, or soy formula

BACKGROUND AND OBJECTIVE

Although soy formula has been reported to support normal development, concerns exist regarding potential adverse developmental effects of phytochemicals associated with soy protein. This study characterized developmental status (mental, motor, and language) of breastfed (BF), milk-based formula-fed (MF), or soy protein-based formula-fed (SF) infants during the first year of life.

METHODS

Healthy infants (N = 391) were assessed longitudinally at ages 3, 6, 9, and 12 months. Development was evaluated by using the Bayley Scales of Infant Development and the Preschool Language Scale-3. Mixed effects models were used while adjusting for socioeconomic status, mother's age and IQ, gestational age, gender, birth weight, head circumference, race, age, and diet history.

RESULTS

No differences were found between formula-fed infants (MF versus SF). BF infants scored slightly higher than formula-fed infants on the Mental Developmental Index (MDI) score at ages 6 and 12 months (P < .05). Infants who were breastfed also had higher Psychomotor Development Index scores than SF infants at age 6 months and slightly higher Preschool Language Scale-3 scores than MF infants at ages 3 and 6 months (P < .05). In addition, BF infants had a lower probability to score within the lower MDI quartile compared with MF infants and a higher likelihood to score within the upper quartile for the MDI and Psychomotor Development Index compared with SF infants.

CONCLUSIONS

This unique study showed that all scores on developmental testing were within established normal ranges and that MF and SF groups did not differ significantly. Furthermore, this study demonstrated a slight advantage of BF infants on cognitive development compared with formula-fed infants.

Nutrient enrichment of mother's milk and growth of very preterm infants after hospital discharge

OBJECTIVE

To determine if the addition of a multinutrient human milk fortifier to mother's milk while breastfeeding very preterm infants after hospital discharge is possible and whether it influences first-year growth.

METHODS

Of a cohort of 320 infants (gestational age: 24-32 weeks; birth weight: 535-2255 g), breastfed infants (65% [n = 207]) were randomly assigned shortly before hospital discharge to receive either unfortified (n = 102, group A) or fortified (n = 105, group B) mother's milk until 4 months' corrected age (CA). The remaining infants were bottle-fed with a preterm formula (group C). Follow-up was performed at term and at 2, 4, 6, and 12 months' CA.

RESULTS

Mean duration of breastfeeding after term was not significantly different between groups A and B (11.8 and 10.6 weeks, respectively). Weight, length, and head circumference were not significantly different between groups A and B at 12 months' CA. Compared with groups A and B, infants in group C had a higher increase in weight z score until term and in length z score until 6 months' CA. At 12 months' CA, boys in group C were significantly longer and heavier compared with those in groups A and B, whereas girls in group C were longer and heavier compared with those in group A only. A higher protein intake was related to a higher serum urea nitrogen level and growth.

CONCLUSIONS

Fortification of mother's milk after hospital discharge while breastfeeding very preterm infants was possible without influencing breastfeeding duration but did not significantly influence growth parameters at 1 year of age compared with unfortified mother's milk.

Placental chorioamnionitis at term: epidemiology and follow-up in childhood

The objective was to identify histologic chorioamnionitis ("amnionitis") in the placental disc at term and to investigate associations with demographic, lifestyle, and pregnancy factors and with allergic diseases, atopy, and intelligence quotients in childhood. The setting was a population-based case control study of small-for-gestational age infants at term. One thousand and twelve placentas were assessed histologically for amniocentric inflammation of fetal and/or maternal origin using conservative criteria. Data were collected at birth by maternal interview and from medical records. Follow-up data were obtained from 439 and 418 children at 3.5 and 7 years of age, respectively. Amnionitis was identified in 145 placentas (14.3%), with maternal reaction in 97.2% and fetal reaction in 48.3%. In multivariable analysis any amnionitis was significantly associated with a time from membrane rupture to delivery of 6 to 12 hours, but not with times beyond 12 hours, a duration of total labor exceeding 12 hours, ethnicity (incidences ranging from 8.8% in Indians to 23.5% in Chinese), male infant gender, and anaesthesia during labor, and amnionitis was negatively associated with induction of labor. No associations were found with later allergic disease, atopy, or intelligence quotients. This high incidence of histologic amnionitis at term is similar to historical estimates, despite large reductions in time-related risk factors during labor. Significant ethnic variations contribute to the high incidence and are unexplained, but variation in genetic polymorphisms for susceptibility factors is a possibility. "Silent" histologic amnionitis is a frequent cause of fetal immune activation with potential effects in later life.

Infant feeding practice and childhood cognitive performance in South India

AIM

Several studies have suggested a beneficial effect of infant breastfeeding on childhood cognitive function. The main objective was to examine whether duration of breastfeeding and age at introduction of complementary foods are related to cognitive performance in 9- to 10-year-old school-aged children in South India.

METHODS

The authors examined 514 children from the Mysore Parthenon birth cohort for whom breastfeeding duration (six categories from <3 to > or = 18 months) and age at introduction of complementary foods (four categories from <4 to > or = 6 months) were collected at the first-, second- and third-year annual follow-up visits. Their cognitive function was assessed at a mean age of 9.7 years using three core tests from the Kaufman Assessment Battery for children and additional tests measuring long-term retrieval/storage, attention and concentration, visuo-spatial and verbal abilities.

RESULTS

All the children were initially breastfed. The mode for duration of breastfeeding was 12-17 months (45.7%) and for age at introduction of complementary foods 4 months (37.1%). There were no associations between longer duration of breastfeeding, or age of introduction of complementary foods, and cognitive function at 9-10 years, either unadjusted or after adjustment for age, sex, gestation, birth size, maternal age, parity, socio-economic status, parents' attained schooling and rural/urban residence.

CONCLUSIONS

Within this cohort, in which prolonged breastfeeding was the norm (90% breastfed > or = 6 months and 65% breastfed for > or = 12 months), there was no evidence suggesting a beneficial effect of longer duration of breastfeeding on later cognitive ability.

Three randomized controlled trials of early long-chain polyunsaturated Fatty Acid supplementation on means-end problem solving in 9-month-olds

This study examines whether feeding infants formula supplemented with long-chain polyunsaturated fatty acids (LCPUFA) improves cognitive function of 9-month-olds. Participants included 229 infants from 3 randomized controlled trials. Children received either formula supplemented with docosahexaenoic acid and arachidonic acid, or a control formula beginning at 1-5 days (12-month feeding study), or following 6 weeks (6-week-weaning study) or 4-6 months of breastfeeding (4-to 6-month weaning study). Infants were assessed with a 2-step problem solving task. In the 12-month feeding and 6-week weaning studies, supplemented children had more intentional solutions (successful task completions) and higher intention scores (goal-directed behaviors) than controls. These results suggest that LCPUFA supplementation improves means-end problem solving.

Infant feeding attitudes and knowledge among socioeconomically disadvantaged women in Glasgow

OBJECTIVES

This study: (1) investigated infant feeding attitudes and knowledge among socioeconomically disadvantaged mothers in an urban community with historically low breastfeeding rates, (2) examined the influence of women's social networks on infant feeding attitudes and decisions, and (3) validated a measure of infant feeding attitudes and knowledge in this population (Iowa Infant Feeding Attitude Scale, IIFAS).

METHODS

Women attending a prenatal clinic (n=49) reported on: (1) demographics, (2) infant feeding attitudes and knowledge (IIFAS), (3) feeding intent, (4) opinions about breastfeeding in public, and (5) social networks. Feeding method at discharge was abstracted from hospital charts. Social network members (n=47) identified by the prenatal sample completed interviews covering: (1) demographics, (2) infant feeding attitudes and knowledge (IIFAS), (3) prior infant feeding methods and recommendations, and (4) opinions about breastfeeding in public.

RESULTS

Mean IIFAS scores were low in both groups, indicating neutral to negative breastfeeding attitudes; mothers' scores were lower than social network members. Higher maternal IIFAS score was significantly associated with intended and actual breastfeeding. A social network positive towards breastfeeding was significantly associated with mothers' positive attitude towards breastfeeding. Both mothers and social network members support breastfeeding in public. IIFAS internal consistency was robust for both mothers and social network members. Predictive validity was demonstrated by significant positive association between score and intended and actual feeding methods.

CONCLUSIONS

Knowledge and attitude predict breastfeeding initiation in this population. Social network members may influence mothers' feeding choices. This research is important because attitudes and knowledge derived from the IIFAS can be used to develop and evaluate breastfeeding promotion programs.

Use of contemporary antidepressants during breastfeeding: a proposal for a specific safety index

Despite the well known severe repercussions of maternal depression on infants' well being, women are often reluctant to seek pharmacological treatment for postnatal depression. The fear of adverse events for the suckling infant plays an important role in such maternal considerations. However, the pharmacological approach to mood disorders at postpartum onset often represents one of the most realistic options in a number of clinical conditions. Therefore, the necessity exists to establish the safety of antidepressant treatment in the breastfed infant. For this reason, the aim of this article is to propose a specific safety index that assesses the frequency and degree of severity of adverse events in infants associated with maternal treatment with second-generation antidepressants during puerperium. The index is derived from a simple formula that uses the number of reports of adverse events in infants exposed to antidepressants as the numerator and the combined total of reports of healthy outcomes and reports of adverse events as the denominator. The sum is then multiplied by 100. A value of < or =2 indicates that the drug should be relatively safe for use during breastfeeding, a value of 2.1-10 indicates that the drug should be used with great caution and a value >10 indicates that the drug should be contraindicated in breastfeeding mothers. In addition to the figure created by this calculation, each drug will also be assigned a letter or the combination of a letter and a subscripted number to symbolise, respectively, the type and clinical management of the most serious recorded event. At this early developmental stage of the index, a complete classification of contemporary antidepressants regarding their safety in infants nursed to the breast is unfeasible. Indeed, because of the lack of suitable published data, so far the index has been limited to the evaluation of four antidepressants. In accordance with the index classification for these four antidepressants, sertraline and paroxetine should be considered as first-line medications in women who need to start antidepressant treatment during the postpartum period and wish to continue breastfeeding. The utilisation of fluoxetine and citalopram seems conversely to be associated with a relatively higher risk of adverse events (with a low degree of severity, however). For the other newer antidepressant drugs, the index is still of no assistance to the patient or physician in deciding on the safety of their use in lactation.