Neurological evaluation of the maturity of newborn infants.

Abstract

Cerebral maturation during the last three months of fetal life brings about constant modification of muscle tone and of certain reflexes.This has enabled a scheme to be devised, whereby the neurological maturity of the premature infant at different ages can be assessed.Saint-Anne Dargassies (1955) defined this neurological progression by analysing a group of 100 prematures of known gestational age, and the longitudinal evolution of healthy prematures, born at 28 weeks' gestational age and studied up to 40 weeks' gestational age.The clinical results have been compared with the electroencephalographic (Dreyfus-Brisac, Flescher, and Plassart, 1962) and anatomical (Larroche, 1962) stages of development of the brain.In applying this maturation scheme to 'small-for-dates' babies it has been concluded that brain development during fetal life progresses independently of unfavourable gestational circumstances.Chronic fetal stress is reflected mainly in the birthweight and to a lesser degree in the body length at birth.The brain, however, from the point of view of anatomy and physiology, evolves more in proportion to the gestational age (Gesell and Amatruda, 1945; Bergstrom, Gunther, Olow, and Soderling, 1955; Saint-Anne Dargassies, 1955).The original observations on which this paper is based are those of Minkowski, Larroche, Vignaud, Dreyfus-Brisac, and Saint-Anne Dargassies (1966).This paper presents a practical method for applying clinically the principles described by these authors.Butler and Bonham (1963) estimated that a third of infants weighing less than 2500 g. have a gestational age greater than 38 weeks.The small-for-dates baby is liable to develop serious metabolic distur- bance shortly after birth; for this reason it is imperative that the assessment of gestational age be made early.Occasionally the initial neurological evaluation of maturation is confused by signs of neurological disorders.But, as a rule, neurological examination during the first days of life can provide