Study of a group of extremely preterm infants (25-27 weeks): How do they function at 1 year of age?

The functional outcome of 49 extremely preterm infants (gestational age: 25 -27 weeks) was studied at the corrected age of 12 months. Apart from pediat ric follow-up, a full neurologic assessment and the Bayley Motor and Mental Scales of Infant Development was done. Emphasis was placed on postural con trol, spontaneous motility, hand function, and elicited infantile reactions . Special attention was given to symmetric development. The infants were th en categorized as having optimal or nonoptimal or asymmetric outcome. Overa ll, an optimal outcome was found in 19 infants (39%) and nonoptimal outcome in 30 infants (61%), 7 of whom failed on all domains of function. Postural control had a significant influence on the different domains of developmen t such as motility (P less than or equal to .001) and persistent infantile reactions (P less than or equal to .001) and slightly less on hand function (P=.08) and asymmetry (P=.06). The outcome on spontaneous motility was sig nificantly related to the results on infantile reactions (P less than or eq ual to .005) and hand function (P=.05). Also, the score on the motor scale of the Bayley Developmental test was clearly related to outcome on spontane ous motility (P less than or equal to .001) and reactions (P less than or e qual to .02). Abnormal brain ultrasonograms were related to the asymmetry o f the infantile reactions (P less than or equal to .05). Poor coordination of gross motor function will have consequences for appropriate visuomotor a nd sensorimotor integration, thereby hampering motor learning and later cog nitive function, as is often described in preterm infants. It is suggested that the poor postural control found in many infants born preterm is the re sult of both myogenic and neurogenic deviations caused by the preterm birth and its nursing consequences.