Six months of breastfeeding tied to lower risk of developmental delays | Image Credit: © evso - © evso - stock.adobe.com.

Children breastfed for at least 6 months had reduced odds of developmental delays and neurodevelopmental conditions, according to a cohort study using national Israeli data, published in JAMA Network Open.

Developmental impact of breastfeeding

“Detecting and addressing potentially modifiable factors associated with healthy development is key to optimizing a child’s potential,” wrote the study authors, led by Inbal Goldshtein, PhD, of KI Research Institute, Kfar Malal, Israel. “When investigating the outcomes of child development, it is important to account for disparities in feeding practices and avoid confounding bias.”

The study used data from 570,532 children (51.2% male) born between 2014 and 2020 after 35 weeks’ gestation. Of this group, 20,642 (3.6%) were preterm, 38,499 (6.7%) were small for gestational age, and 297,571 (52.1%) were breastfed for at least 6 months (123 984 [41.7%] were exclusively breastfed).

Children with severe illness or extended hospitalization at birth were excluded. Breastfeeding exposure was defined by duration and exclusivity, and outcomes included delays in milestone attainment and diagnosis of neurodevelopmental conditions (NDCs).

Adjusted outcomes for milestone delays

Children who were breastfed for at least 6 months had lower adjusted odds of milestone delays compared to those breastfed for less than 6 months. For exclusive breastfeeding, the adjusted odds ratio (AOR) was 0.73 (95% CI, 0.71–0.76); for nonexclusive breastfeeding, the AOR was 0.86 (95% CI, 0.83–0.88).

In a subgroup of 37,704 sibling pairs, children who were breastfed for 6 months or longer were also less likely to have delays in milestone attainment (OR, 0.91; 95% CI, 0.86–0.97) or receive a neurodevelopmental diagnosis (OR, 0.73; 95% CI, 0.66–0.82) compared with their sibling who received less or no breastfeeding.

Broader data sources strengthen findings

Investigators linked data from Israel’s Mother-Child Health Clinics, which conduct standardized surveillance visits for 70% of the pediatric population, with government records of disability entitlements. These entitlements reflect only moderate-to-severe functional conditions and are not granted for diagnosis alone.

The associations between breastfeeding and outcomes were consistent among late-preterm (35–36 weeks) and term/postterm infants. The absolute benefit appeared greater in preterm children due to higher baseline NDC prevalence.

Policy considerations and barriers

Although causality could not be established, the findings supported global recommendations encouraging breastfeeding. “The WHO strongly endorses breastfeeding, yet a gap remains between feeding recommendations and actual practices,” the authors stated.

They emphasized that breastfeeding is influenced by social, structural, and commercial forces, noting, “Breastfeeding is a learned behavior on the part of the mother and child and thrives best when there is adequate promotion, protection, and support. The aim of this study was not to alter or reduce neurodivergence but rather to maximize each individual child’s abilities and minimize functional gaps,” they wrote.

Conclusion

These findings, that breastfeeding for 6 months or longer was associated with lower odds of developmental delays and neurodevelopmental diagnoses, may inform counseling, public health guidance, and support strategies for early childhood development.

The authors stated that a study strength was the large, nationwide population sample along with critical confounders data availability. This use of routine surveillance data reduced risk of recall bias. Limitations listed by the authors included the risk of confounding by infant illness, as the investigators could not rule out that some illnesses were not completely captured. Additionally, parental engagement and dedication or paternal intelligence are unmeasured confounders which were mitigated by the within-family design, though siblings analysis was not feasible for preterm children.

Reference:

Goldshtein I, Sadaka Y, Amit G, et al. Breastfeeding Duration and Child Development. JAMA Netw Open. 2025;8(3):e251540. doi:10.1001/jamanetworkopen.2025.1540