Development of breastfeeding behavior in preterm infants : Behavioral and neurophysiological evidence of early competence

Sammanfattning: The objectives of this thesis were to develop a method for observation of maturational steps in preterm infants' breastfeeding behavior, test the reliability and validity of this method, describe this development and explore effects of certain infant and maternal factors on infant breastfeeding behavior. The Preterm Infant Breastfeeding Behavior Scale (PIBBS) was developed. Surface electromyography (EMG) was used for the first time for registration of breastfeeding behavior in preterm infants.A high level of agreement was obtained for PIBBS observations by two observers and by observers and mothers, and for simultaneous observation and EMG data. A very preterm infant's behavior was described according to the Newborn Individualized Developmental Care and Assessment Program. Prospective PIBBS data was obtained in 4321 observations by mothers' of 71 infants born after 26-35 gestational weeks, from initiation of breastfeeding until infants' discharge.Irrespective of postmenstrual age, infants rooted and sucked on the first day with breastfeeding. Efficient rooting, areolar grasp and latching on were observed at 28 weeks, nutritive sucking at 30 weeks, and repeated bursts of >-10 sucks at 31 weeks. Fifty-seven infants were breastfed fully at discharge and ten partly. Full breastfeeding was established at 33-40 weeks. Higher PIBBS scores were associated with higher birthweight, less need of ventilator and oxygen treatment, higher hemoglobin level, no need of Theophylline treatment,no suspicion of infection, absence of bottle-feeding, and mothers' breastfeeding experience.Observation and surface EMG are recommended as reliable and valid methods for assessment of preterm infants' breastfeeding behavior. Infants' early sucking competence is interpreted as an effect of a learning experience, enhanced by contingent stimuli.