Delivery mode and altered infant growth at 1 year of life in India.

BACKGROUND Cesarean section (C-section) delivered infants are more likely to be colonized by opportunistic pathogens, resulting in altered growth. We examined whether C-section (elective/emergency) vs vaginal delivery was associated with altered weight and linear growth at 1 year of life. METHODS A total of 638 mother-infant pairs were included from MAASTHI cohort 2016-2019. Information on delivery mode was obtained from medical records. Based on WHO child growth standards, body mass index-forage z-score (BMI z) and length-for-age z-score (length z) were derived. We ran multivariable linear and Poisson regression models before and after multiple imputation. RESULTS The rate of C-section was 43.4% (26.5%: emergency, 16.9%: elective). Percentage of infant overweight was 14.9%. Compared to vaginal delivery, elective C-section was associated with β = 0.57 (95% CI 0.20, 0.95) higher BMI z. Also infants born by elective C-section had RR = 2.44 (95% CI 1.35, 4.41) higher risk of being overweight; no such association was found for emergency C-section. Also, elective C-section delivery was associated with reduced linear growth at 1 year after multiple imputation (β = -0.38, 95% CI -0.76, -0.01). CONCLUSIONS Elective C-section delivery might contribute to excess weight and also possibly reduced linear growth at 1 year of age in children from low- and middle-income countries. IMPACT Our study, in a low-income setting, suggests that elective, but not emergency, C-section is associated with excess infant BMI z at 1 year of age and elective C (C-section) was also associated with altered linear growth but only in multiple imputation analyses. Elective C-section was associated with a higher risk of being overweight at 1 year of age. Our results indicate that decreasing medically unnecessary elective C-section deliveries may help limit excess weight gain and stunted linear growth among infants.