Investigating Relations between the NICU Speech Environment and Weight Gain in Infants Born Very Preterm

Objective Children born preterm, especially those born very preterm (< 32 weeks of gestational age [GA]) are at risk for poor growth and adverse neurodevelopmental outcomes. Adverse growth and neurodevelopmental outcomes in preterm children have been attributed, in part, to the aversive sounds and relative speech paucity of the neonatal intensive care unit (NICU). Experimental studies that directly expose preterm infants to speech sounds in the NICU find significant improvements in health factors relevant to neurodevelopment. Few studies have examined whether natural variations in the speech environment of the NICU are related to short-term health outcomes in preterm infants. Such data are important for optimizing the sound environment of the NICU. Our objective was to examine relations between the NICU speech environment and the rate of weight gain during hospitalization.Study Design Participants were infants born very preterm ( n = 20). The speech environment of each infant was assessed at 32 to 36 weeks of postmenstrual age using an automatic speech-counting device. Average rates of weight gain (g/kg/d) were ascertained over the same period. Calories were derived from charted intake (kcals/kg/d). Linear regressions examined caloric intake and speech counts as predictors of infant weight gain.Results Infant weight gain was significantly predicted by caloric intake and speech exposure, each uniquely accounting for approximately 27% variance (total R (2) = 60.2%; p < 0.001). Speech counts were uncorrelated with rates of family visitation, time in incubator, or health acuity.Conclusion While future research should establish causality and direction of effects, enhancing speech exposure in the NICU may be beneficial for physical growth. NICU care plans should consider opportunities to increase speech exposure.