[Weight/head circumference ratio at birth for assessing fetal growth]

The scope of this article was to use the weight/head circumference ratio at birth to assess fetal growth. A cross-sectional study was conducted in a birth cohort in the State of Paraíba, Northeast of Brazil, with 726 children born at term and weighing 2,500 grams or more. The anthropometric measurements, sociodemographic characteristics, gestational care and type of delivery were collected in the first 24 hours after birth of infants were assessed. Infants were classified as proportionate (weight/head circumference ratio ≥0.87) versus disproportionate (<0.87). Lower mean weight/head circumference ratio was identified in newborns of lower gestational age, with lower birth weight, female, from families not benefiting from the Bolsa Família Program, of mothers who did not take folic acid during pregnancy and were born by cesarean section. Mean weight, length, and head circumference were lower among infants with disproportionate weight/head circumference ratio, independently of sex. Weight/head circumference ratio is an important indicator of fetal growth.