Home observations of high-risk premature infants and their mothers during the first year of life: A microanalytic behavioral study.

Abstract

This study investigates behavioral interactions among mothers and their extremely low birth weight (ELBW, birth weight $<$ 1250 grams) preterm infants at four and eight months of age from an ethological-evolutionary perspective. The main objective is to determine whether these behavioral patterns support the "compensation" or the "overstimulation" hypothesis. The "compensation" hypothesis suggests that mothers are responding appropriately to the signals and special needs of their ELBW infant, resulting in mutually rewarding engagement. The "overstimulation" hypothesis suggests that mothers are overactive and insensitive to infant signals, causing ELBW infants to withdraw and/or fuss, thus decreasing the likelihood of positive engagement. A second objective was to examine how infant health characteristics affected maternal behavior towards ELBW twins. Naturalistic observations of mothers and 94 singleton infants (41 ELBW and 53 full-term) and 14 ELBW twin infants were conducted at four and eight months of infant age (corrected for gestational age in the ELBW group). Simultaneous and sequential frequencies and durations of behaviors were recorded continuously during home observations. Behaviors were examined in isolation (durations and frequencies), and in context (rates and durations of co-occurring behaviors). Analyses of group (ELBW vs. full-term) behavioral differences at four and eight months supported the "compensation hypothesis." Mothers engaged their ELBW infants in more proximate interactions relative to mothers of full-term infants, resulting in equal amounts of reciprocal engagement between groups. ELBW infants were less vocal than full-term infants, but sequential and contextual analyses of vocal patterns revealed that ELBW infants were not less vocally responsive. Risk status of ELBW infants also affected maternal behavior. Mothers were more attentive to higher-risk ELBW infants compared to lower-risk ELBW infants, although the nature of this involvement differed depending on the child's characteristics. ELBW infants who experienced neurological insult received more proximate stimulation, whereas ELBW infants who experienced severe respiratory problems received more distal stimulation at eight months. However, under more stressful circumstances, such as with ELBW twins, mothers gave preferential treatment to their healthier infant. Overall, mothers of preterm infants are best characterized as adjusting to, not insensitive to, infant signals and characteristics.