Factors Affecting Neurobehavioral Responses of Preterm Infants at Term Conceptional Age

Abstract

A revised Prechtl Neurological Examination was administered to 510 singleton infants at term conceptional age to assess the influence of gestational age, race, and sex on neurobehavioral responses in a "typical" newborn population. The infants were born at 1 of 5 centers and were subjects of the NIH Collaborative Study on Antenatal Steroid Therapy. Of these babies, 392 were born at less than 37 weeks gestational age, whereas 118 infants were born at greater than or equal to 37 weeks. Of a total of 50 items of interest, 12 differed significantly based on race, 14 items differed in terms of gestational age at birth, and 5 items were influenced by the sex of the baby. These data suggest that singleton preterm infants born at differing gestational ages should not be considered to comprise a homogeneous sample. Further, caution should be exercised when considering babies of heterogeneous race groupings, and the babies' sex has minimal impact on neurobehavioral responses at term conceptional age.

Human fetal and neonatal movement patterns: Gender differences and fetal‐to‐neonatal continuity

“…4). Other studies have also reported neonatal gender differences for motility and sensorimotor behaviors, for example, low-intensity activity, patterns of activity development, and performance on neurological exams (Aylward et al, 1984;Buelke-Sam et al, 1984;Phillips et al, 1978). With advancing postnatal development from infant through adolescent ages, gender effects on motor behaviors are frequently reported (e.g., Aaron, Kriska, Dearwater, Anderson, Olsen, Cauley, & Laporte, 1993;Eaton & Enns, 1986;Gabriel, Chilla, & Kozielski, 1976;Johnson & Brody, 1977;Schwartz, Niman, & Gisel, 1984).…”

“…Gender differences have been reported for antenatal studies of hormones (Bayer et al, 1994;Hines, 1982;Meyer-Bahlburg et al, 1988;Reinisch, 1974;Toran-Allerand, 1984), nervous system (Beaston-Wimmer & Smolen, 1991;Engele, Pilgrim, & Reisert, 1989;Hutchison et al, 1994;de Lacoste et al, 1986;Patchev, Hayashi, Orikasa, & Almeida, 1995;Schindler, 1975), surfactant production and lung development (Hanley et al, 1996;Neilsen & Torday, 1981), biochemistry and immunology (Romero, Gomez, Galasso, Mazor, Berry, Quintero, & Cotton, 1994), and somatic growth (Ounsted et al, 1981, Scott, Guardian, Angelus, & Backstrom, 1991Sumulian et al, 1995). For newborn infants, there are reports of gender differences for motility and sensorimotor behaviors (Aylward et al, 1984;Buelke-Sam et al, 1984;Eaton & Enns, 1986;Phillips et al, 1978), as well as perinatal gender differences for the incidence of preterm birth (McGregor, Leff, Orleans, & Baron, 1992) and for perinatal mortality (Perelman, Palta, Kirby, & Farrell, 1986). The antenatal biological studies (particularly the hormonal, nervous system and growth studies) and the neonatal motor behavior studies converge to indicate that gender differences for antenatal movements might be expected, based on differential biological and behavioral developmental patterns for male and female fetuses and neonates.…”

“…For example, antenatal studies of humans and other animals report gender differences for measures of hormones (Bayer, Green, & Hutchison, 1994;Hines, 1982), nervous system (Hutchison, Bayer, Green, & Wozniak, 1994;de Lacoste, Holloway, & Woodward, 1986), somatic growth (Ounsted, Scott, & Moar, 1981;Sumulian, Campbell, Rodis, Feeney, Fabbri, & Vintzileos, 1995), and lung development (Hanley, Rassner, Jiang, Vansomphone, Crumrine, Komuves, Elias, Feingold, & Williams, 1996;Nielsen & Torday, 1981), among others. Further, postnatal studies report gender differences for motility and sensorimotor behaviors for human infants (Aylward, Hatcher, Leavitt, Rao, Bauer, Brennan, & Gustafson, 1984;Buelke-Sam, Sullivan, Kimmel, & Nelson, 1984;Eaton & Enns, 1986;Phillips, King, & DuBois, 1978). Combined, the fetal hormone, nervous system and somatic growth research plus the neonatal movement studies indicate the potential for gender differences for fetal movement patterns.…”

Early tactile experience of low birth weight children: links to later mental health and social adaptation

“…Frequent touch may especially overload their neural apparatus, impeding their ability to process the myriad stimuli to which they are exposed. Less responsive infants with more complicated courses show both a diminished ability to modulate their arousal (Aylward et al, 1984) and substantial avoidance of interaction (Bennett, 1997) in an apparent attempt to manage their arousal. In addition, the painful probing and pricking experienced by very high risk infants in the course of their medical care may create some tactile aversion in these children which impedes their ability to effectively integrate tactile input later on (DeMaio-Feldman, 1994).…”

Avaliação da idade gestacional de recém-nascidos pré-termo através do exame neurológico e das escalas neonatais e obstétrica

“…A mortalidade perinatal e a incidência de sequelas neurológicas em crianças prematuras têm diminuído, dados os avanços da perinatologia 5,6 . Mesmo as crianças de muito baixo peso ao nascer têm melhores chances de sobrevivência e estão menos sujeitas à elevada incidência de severas sequelas 5,7,8 .…”