Breastfeeding linked to lower risk of developmental delays

Breastfeeding linked to lower risk of developmental delays | Image Credit: © Анастасія Стягайло - © Анастасія Стягайло - stock.adobe.com.

Breastfeeding and developmental outcomes

The risks of developmental delays and language or social neurodevelopmental conditions are reduced by exclusive or longer duration breastfeeding, according to a recent study published in JAMA Network Open.¹

Guidelines from the World Health Organization encourage exclusive breastfeeding in the first 6 months of life and up to 2 years of breastfeeding complemented by healthy foods.² However, while data has noted the impact of nutrition on physical and cognitive development early in life, investigators have noted cofounding bias in studies assessing breastfeeding outcomes.¹

“Many studies classify breastfeeding as a dichotomy, that is, either breast milk or formula feeding within a prespecified time window, whereas in practice, many infants receive both,” wrote investigators. “Therefore, it is of interest to investigate the duration of any breastfeeding, not necessarily exclusive breastfeeding.

Study design and data collection

The cohort study was conducted to evaluate the link between breastfeeding and child development in early-term to postterm and late-preterm children, defined as 37- to 42-weeks’ gestation and 35- to 36-weeks’ gestation, respectively. Data was obtained from mother-child health clinics (MCHCs) and insurance disability entitlements records.

The research platform TIMNA was used to extract data from MCHCs, which offer free pediatric preventive services such as vaccinations, early detection of health problems, and education to children aged up to 6 years. Visits are recommended at birth and at 1, 2, 4, 6, 9, 12, 18, 24, 38, 48, and 60 months.

Study population and breastfeeding classification

Children born from January 2014 to December 2020 were included in the analysis. Eligibility criteria included having at least 1 follow-up visit when aged 2 to 3 years, being born after 35 weeks’ gestation, having no severe illness, and being discharged from the hospital within 5 days of birth. Population diversity was determined through self-reported ethnicity.

Child nutrition was recorded in an electronic form during interviews between the mothers and nurses at each visit. During the interviews, nurses asked mothers whether they had breastfed, if they had ceased, and the age at cessation.

Reported categories of breastfeeding included less than 6 months of feeding, at least 6 months of nonexclusive feeding, and at least 6 months of exclusive feeding. Continuation breastfeeding of any duration was also reported.

Developmental milestones and outcome measures

Investigators collected outcome data such as delayed attainment of milestones and diagnosis of a neurodevelopmental condition (NDC) in March 2023. MCHC visit records were assessed to determine milestone delays based on the Tipat-Halav Israeli Surveillance standardized scale.

There were 3 language or social milestones and 3 gross or fine motor milestones assessed when patients were aged 24 to 36 months. Not attaining at least 2 of 3 milestones was considered milestone delay. NDCs were based on National Insurance Institute of Israel entitlements.

Key findings

Of children born from 2014 to 2020, 570,532 were included in the final analysis, 48.8% of whom were female and 51.2% were male. Birth in early term to postterm was reported in 96.4%, preterm birth in 3.6%, breastfeeding for at least 6 months in 52.2%, milestone attainment delay in 6.5%, and an NDC in 2.5%.

Exclusive breastfeeding was performed in 21.7% of the cohort, while 30.4% received nonexclusive breastfeeding. The remaining 47.8% of infants were not breastfed.

The odds of milestone attainment delay were reduced among infants with breastfeeding, with an adjusted odds ratio (aOR) of 0.86 for nonexclusive breastfeeding and 0.73 for exclusive breastfeeding. Significant differences in motor NDC rates were not observed between groups.

Longer breastfeeding was associated with a gradual decline in the aOR, especially during the first months of life. However, this was not linked to reduced motor MDC risk. When matching the cohort for covariates, the aOR for milestone attainment delay was 0.83.

Conclusion and public health implications

For language or social milestone delay and motor milestone delay, the aORs were 0.82 and 0.88, respectively. For language and social NDC, undetermined NDC, and motor NDCs, the aORs were 0.72, 0.74, and 0.76, respectively. This data highlighted the link between breastfeeding persistence and reduced odds of developmental delays.

“These findings may guide parents, caregivers, and public health initiatives in promoting optimal child development,” concluded investigators.

References

1. 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
2. Meek JY, Noble L; Section on Breastfeeding. Policy statement: breastfeeding and the use of human milk. Pediatrics. 2022;150(1):e2022057988. doi:10.1542/peds.2022-057988