[Recommendations for the assessment of birth size and postnatal growth of preterm newborns].

It is unquestionable the need to have standards of size at birth and growth to evaluate and contribute to guide the actions in the care of the newborn. For many years the references of Lejarraga and Fustiñana were used, progressively replaced by those of Fenton and Kim. However, recently, the INTERGROWTH-21st project has developed prescriptive growth standards to evaluate the size at birth from 33 weeks of gestational age, references from 24 to 32.6 weeks of gestational age, and curves for postnatal growth from 27 weeks of gestational age onward. The Growth and Development and Neonatal Fetal Studies Committees of the Argentine Society of Pediatrics in conjunction with the Secretary of National Government of Health agreed to recommend the replacement of the Fenton and Kim curves with those of INTERGROWTH-21st.