The impetus for shorter hospital stay of mother and newborn infant after delivery is based on economic constraints and parental preference. Earlier published studies did not demonstrate any increase in morbidity rate with shorter stay, but these studies were limited by methodologic flaws and biases that limited the validity and generalizability of the conclusions. More recent studies showed that readmission rates increased with shorter stay and that the severity of illness of readmitted infants may have increased. In addition, the interpretation of current newborn screening tests may not be applicable when performed prior to early discharge. In light of recent changes in neonatal hospital length of stay, a careful review and update of current guidelines and practices for newborn care are required.