Neonatal Neurobehaviour I: Development and its Relation to Obstetric Medication

SUMMARY

A general critique of the large body of research on the neonatal behavioural effects of obstetric medication is given to provide the clinician with a better framework within which to conceptualize the problem. Study designs are examined to illustrate limitations in the interpretations of the findings. Investigators often fail to consider principles of perinatal pharmacology when researching drug effects and do not include control samples of infants of unmedicated deliveries. The effects of other perinatal variables which may interact with drug effects are generally ignored. Furthermore, many of the dependent measures of behaviour which are assessed do not adequately conceptualize neonatal behavioural functioning. A description of the Brazelton Neonatal Behavioral Assessment Scale is given as an example of a measure which examines neonatal behavioural functioning within an interactive setting. It is recommended that changes in behaviours over time be investigated to assess drug effects on the infant's recovery from labour and delivery. A recent study which investigated the effects of bupivacaine epidural anaesthesia and obstetric variables that alter its rate of placental transfer is discussed. Findings showed synergistic effects of bupivacaine and the perinatal variables on neonatal behavioural functioning and recovery from labour and delivery up to one month of age, but not at one year.

The chapter illustrates that research findings do not support a simple, linear picture of drug effects on behaviour. A systems approach is suggested, in which neonatal behavioural functioning and parent-infant interaction are viewed in the light of the interaction of maternal characteristics that influence medication decisions, the medication, and maternal and fetal conditions which alter its placental transfer. Ultimately, it is these systems that affect the infant's developmental outcome.