Peer-reviewed article
Caesarean section may be associated with suspected motor developmental delay at 3 years of age in the Japan Environment and Children's Study.
Sanzen I, Matsumura K, Inano H, Tsuchida A, Sakai J et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study of over 53,000 Japanese mother-child pairs examined whether babies born by caesarean section had higher rates of developmental delay at age 3. While no overall link was found between delivery method and developmental delay, the analysis by sex revealed that boys born by caesarean section had higher rates of gross motor delay, and girls had higher rates of fine motor delay. The findings suggest a possible connection between caesarean delivery and motor developmental delay in early childhood.
Key points
- No significant overall relationship was found between mode of delivery and suspected developmental delay across all children
- Boys born by caesarean section had 27% increased risk of suspected gross motor developmental delay compared to those born vaginally
- Girls born by caesarean section had 34% increased risk of suspected fine motor developmental delay compared to those born vaginally
- The study used the Ages and Stages Questionnaires, Third Edition to assess developmental delay at 3 years of age
- Multivariate logistic regression analysis was used to calculate adjusted odds ratios accounting for other factors
Limitations
The study is observational and cannot establish causation; it relied on parent-reported questionnaires rather than clinical diagnostic assessment of developmental delay. The mechanism linking caesarean delivery to motor delays and the reasons for sex-specific differences remain unclear from this analysis.
Abstract
The number of births by caesarean section (CS) is increasing worldwide. In line with this trend, there is growing interest in the neurodevelopmental outcome of children born by CS. This study examined the relationship between the mode of delivery and suspected neurodevelopmental delay in young children. A total of 53,716 mother-child pairs participating in the Japan Environment and Children's Study, a representative Japanese cohort study of children, were included in the analysis of the association between CS and suspected developmental delay, as assessed by the Ages and Stages Questionnaires, Third Edition, in 3-year-old children. Multivariate logistic regression analysis was performed to calculate adjusted odds ratios (aORs) with 95% confidence intervals (CIs). No significant overall relationship was found between mode of delivery and suspected developmental delay. In an analysis by sex, CS was associated with increased risk of suspected gross motor developmental delay (aOR 1.27, 95% CI 1.07-1.49) in boys and increased risk of suspected fine motor developmental delay (aOR 1.34, 95% CI 1.11-1.63) in girls. These results suggest that there may be a relationship between CS and suspected motor developmental delay at the age of 3 years.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- Delivery by caesarean section versus vaginal delivery
- Population
- 53,716 mother-child pairs from the Japan Environment and Children's Study, a representative Japanese cohort
Key finding
No significant overall relationship between caesarean section and developmental delay across all children
I et al. · Europe PMC · 14 Apr 2026