Maternal and infant factors had a significant impact on birthweight andlongitudinal growth in a South African birth cohort

Aim: This birth cohort study investigated longitudinal infant growth and associated factors in a multiethnic population living in a low-resource district surrounding the town of Paarl in South Africa. Methods: Between March 2012 and October 2014, all mothers attending their second trimester antenatal visit at Paarl Hospital were approached for enrolment. Mother-infant pairs were followed from birth until 12 months of age. Comprehensive socio-demographic, nutritional and psychosocial data were collected at birth, two, six and 12 months. Infant anthropometry was analysed as z-scores for weight and height. Linear regression was used to investigate predictors of birthweight, and linear mixed-effects models were used to investigate predictors of infant growth. Results: Longitudinal anthropometric data from 792 infants were included: 53% were Black African, 47% were mixed race, and 15% were born preterm. Stunting occurred in 13% of infants at 12 months. Maternal height, antenatal alcohol and tobacco use, ethnicity and socioeconomic status were significant predictors of birthweight. In the adjusted mixed-effects model, birthweight was a significant predictor of growth during the first year of life. Conclusion: Birthweight was an important predictor of growth trajectory during infancy. Birthweight and growth were influenced by several important modifiable factors.