Dr. C. Mary Schooling, professor at the CUNY Graduate School of Public Health and Health Policy, along with colleagues from Hong Kong examined the association of late prematurity with markers of adiposity in adolescence and tested whether accelerated infant weight gain mediated the association. Their research was published in Obesity (Silver Spring).
The researcher used data from the Children of 1997, a population-representative Chinese birth cohort. The members of the cohort used in these analyses were born between 34 weeks 0 days and 36 weeks 6 days gestation. Children were followed until age 5 years at the Maternal and Child Health Centres and then once they had entered school, through the Student Health Service.
In adolescence, those with late preterm births had significantly greater body mass index (BMI) z-score, waist-hip ratio z-score, and waist-height ratio z-score, when compared to adolescents born at term. Accelerated infant weight gain was associated with higher BMI, but was not associated with waist-hip ratio or waist-height ratio adjusted for sex, highest parents’ education attainment, mother’s place of birth, presence of birth defects, and pregnancy characteristics (gestational diabetes, preeclampsia, and maternal smoking). The association of late premature birth with BMI was mediated by an indirect effect through accelerated infant weight gain.
The findings suggest that vulnerability to metabolic risk in late premature births may arise through multiple pathways.