Can Pre-Pregnancy Weight Affect Your Baby's Brain Development

Research suggests that a mother’s health before pregnancy may shape her child’s long term brain development(1^✔ ✔Trusted Source
Maternal pre-pregnancy body mass index and the risk of neurodevelopmental disorders in offspring

Go to source). A large population-based study from South Korea now reports that higher maternal pre pregnancy BMI is associated with a greater risk of childhood epilepsy and intellectual disability.

With obesity rising among women of reproductive age, these findings highlight the importance of preconception health.

How Pregnancy Weight Connects to Baby Brain Development

Obesity among young women is increasing in many countries. While it has been known that children of mothers with obesity face greater metabolic risks, evidence is growing that maternal weight may also affect early neurodevelopment.

Previous research has suggested potential links between higher maternal BMI and differences in fetal neural pathways, slower cognitive development and altered emotional regulation.

The new study strengthens this evidence by examining these associations in a very large national population.

Study Design and Data Source

Researchers evaluated data from the Korean National Health Information Database to determine whether maternal BMI measured within three years before pregnancy influences childhood neurodevelopment. BMI categories were assigned using Asia Pacific standards that classify underweight, normal weight, overweight and two levels of obesity.

The analysis included 779091 mother infant pairs who completed maternal and child health screening programs. The researchers also examined gestational age, preterm birth, birth weight, neonatal intensive care admission, and congenital anomalies to account for possible confounders.

Key Findings: Epilepsy and Intellectual Disability Risks Rise

Initial unadjusted analyses showed that children born to mothers with higher BMI had elevated risks of several neurodevelopmental conditions. However, after adjusting for maternal and neonatal characteristics, the most consistent associations remained for childhood epilepsy and intellectual disability. These results represent modest but meaningful increases in risk across rising BMI groups.

Maternal underweight, on the other hand, did not show significant associations in the fully adjusted analysis. The study suggests that elevated maternal BMI may influence fetal brain development through metabolic, inflammatory, or epigenetic mechanisms that begin early in pregnancy.

Associations with autism, attention difficulties and cerebral palsy did not remain significant after full adjustment, suggesting that maternal or neonatal factors accounted for these initial findings.

Importance of Preconception Weight Management

The findings reinforce the idea that pregnancy preparation begins well before conception. A woman’s metabolic environment, including factors linked to excess weight, may affect early neural development.

Supporting women to achieve a healthy weight before pregnancy could reduce certain preventable neurodevelopmental risks in children.

Public health programs aimed at weight care for young women may play an important role in improving long term child health. The results also highlight the value of preconception counseling on nutrition, lifestyle and weight management for women planning pregnancy.

Final Takeaway:

Healthy maternal weight before pregnancy may help lower the risk of epilepsy and intellectual disability in children.

Strengthening preconception care and weight guidance could contribute to better neurodevelopmental outcomes for future generations.

Reference:

1. Maternal pre-pregnancy body mass index and the risk of neurodevelopmental disorders in offspring - (https://www.nature.com/articles/s41366-025-01955-7)

Source-Medindia