Newborn Behavior Research Articles

Newborn Behavioral Effect of Cocaine: Is It Amount of Prenatal Exposure or Acute Toxicity? † 1234

Part of the problem in understanding the nature of early postpartum effects of fetal cocaine exposure has been the lack of separation of true effects of prenatal exposure from those associated with acute toxicity. Only a few studies have compared newborn behavior of infants exposed prenatally and positive for cocaine metabolites at birth to those exposed infants negative for cocaine at birth. Most failed to use blinded observers, drug-free controls, or prospective enrollment. None considered amount of exposure of positive vs. negative infants, thus possibly confounding the effects of amounts of exposure with acute toxicity. We prospectively enrolled 154 women who used cocaine during pregnancy and matched 154 controls on SES, race, parity and prenatal risk. Marijuana was the only other illicit drug allowed. Pregnant women were interviewed in a private setting by trained staff who collected details of past drug use at the end of each trimester. All subjects were required to provide urine specimens at enrollment and to consent to full toxicology testing of their newborns. Following delivery, certified, blinded examiners administrated the Neonatal Behavioral Assessment Scale (NBAS) under controlled conditions. Based on interviews, toxicology testing, and availability for NBAS testing, there were 81 who admitted use or were positive in pregnancy, but whose infants were negative at birth; 48 whose infants were positive at birth; and 148 controls. We determined that median amounts spent on cocaine per day during pregnancy differed for those positive ($1.81) and those negative ($0.66) at birth; therefore, to evaluate acute toxicity, the amount spent on cocaine was used as a covariate in all analyses along with adjustment for amount of tobacco, alcohol and marijuana use. Our results demonstrated that of the 7 NBAS cluster scores, only Autonomic Regulation was significantly different by group. Of the 9 supplementary scores qualifying NBAS performance, only Alert Responsiveness was significant for group; the infants who were positive at birth scored significantly lower than controls, with scores of those negative falling in between. Our earlier work with this cohort found behavioral effects related to the amount of prenatal cocaine exposure. In this study, after controlling for the amount of prenatal exposure, only 2 of 16 NBAS scores were significantly different between infants positive and negative for cocaine metabolites at birth. We conclude that newborn behavioral effects do not seem to be highly related to acute toxicity.

CSF 5-HIAA and family history of antisocial personality disorder in newborns.

The relationship between genetic liability for antisocial behavior and CSF 5-hydroxyindoleacetic acid (5-HIAA) in newborns was explored. The authors assayed 5-HIAA in "leftover" CSF from 193 neurologically normal newborns and obtained family psychiatric histories of the newborns' first- and second-degree relatives. Levels of 5-HIAA were significantly lower in the infants with family histories of antisocial personality disorder than in the newborns without such family histories. These findings support the possibility that serotonin mediates one component of genetic liability to antisocial outcome, but the magnitude of that component may be less than what has been inferred from previously published reports.

Using confirmatory factor analysis to identify newborn behavior structure with the NBAS

The Neonatal Behavioral Assessment Scale (NBAS) (Brazelton, 1973, 1984) is a 27-item scale representing individual differences in the newborn infants' behavioral repertoire. The NBAS items are typically collapsed into six clusters (Lester, 1984). Although the NBAS has been examined using exploratory factor analysis methods, no confirmatory factor analysis study has been published in which the behavior structure of full-term, healthy infants is examined. In the current research, competing models assessing variations of the Lester behavior clusters were performed using confirmatory factor analysis. Models comparing six independent factors, six correlated factors, and models estimating a general adaptiveness factor plus six factors were assessed. Examination of the results suggests continued investigations of neonatal behaviors are needed.

Behavior of Macrosomie and Appropriate-for-Gestational-Age Newborns

To compare the behavior of macrosomic newborns who were vaginally delivered of healthy mothers without diabetes with that of non-macrosomic, appropriate-for-gestational-age (AGA) newborns. Newborns were recruited conveniently from a tertiary hospital. Newborns were examined at 12-24 and 36-48 hours of age, using the Brazelton Neonatal Behavioral Assessment Scale (NBAS). Thirty macrosomic newborns who were delivered vaginally were matched with AGA newborns for ethnicity, maternal education, parity, and obstetric medications. Dimensions scores derived from the individual NBAS items measured reflex functioning, response decrement, orientation, motor processes, range of state, autonomic stability, and regulation of state. Macrosomic newborns performed weaker than AGA newborns on the reflex and motor dimensions. Both groups displayed improved motor scores on Day 2, but regulation of state scores were weaker. For orientation, AGA newborns scored higher on Day 1, and macrosomic newborns scored higher on Day 2. Increased head, limb, and body mass of macrosomic newborns, compared with adjacent and overall muscle strength, might have interfered with the execution of coordinated movements. Nurses can inform mothers of changes they can expect in their newborns' behavior.

Observations of newborn suckling behavior

The suckling behaviors of 11 newborns, who were positioned for breastfeeding with their mouths just touching their mothers' nipple, and who were allowed to try to attach to it without maternal guidance, were videotaped at their very first breastfeeding and 4 days later. Slow-motion analyses revealed that on both days, newborns responded to the nipple with bursts of suckling attempts, which eventually resulted in nipple attachment and sucking. In each suckling attempt, newborns pulled slightly back from the nipple until their mouths were just out of contact with it, then moved toward it while opening their mouths and reestablished contact, all in one smooth motion. This usually ended with the nipple inside the mouth. Thus, when there was no need to search for a nipple, human newborns, like other mammals, exhibit an organized pattern of suckling behaviors that enables them to attach to it on their own.

Assessment of reliability and validity of the behavioral observation record for developmental care.

Due to time constraints, clinicians are rarely able to carry out neurobehavioral assessments that use the Naturalistic Observation of Newborn Behavior Instrument. The content validity, interrater reliability, and criterion-related validity for a less time-consuming instrument, the Modified Infant Behavioral Observation Record (MIBOR) for developmental care was evaluated in this study. Eight developmental care specialists evaluated the MIBOR for content validity. Fifteen infants (birth weight < 1,500 g) were observed to determine interrater reliability, and three were observed to evaluate criterion-related validity. The content validity of the MIBOR, as determined by average congruence, was 96.9%. Interrater reliability for each developmental care subsystem ranged from 67% to 98%. Three of the four subsystems on the MIBOR achieved criterion-related validity, achieving an agreement of r = .60.

A Reconceptualization of the Effects of Undernutrition on Children's Biological, Psychosocial, and Behavioral Development and commentaries

A Reconceptualization of the Effects of Undernutrition on Children's Biological, Psychosocial, and Behavioral Development and commentaries

Activity Level from Birth through First Grade: Stability or Inversion of Intensity?

Two seemingly opposing positions on the stability of behavior related to activity are considered. The first position is that there is stability in activity level beginning very early in development. The second position is the inversion of hypothesis, which posits that intense behavior in the newborn predicts low activity in the third year of life, and newborn behavior which is-lacking in intensity predicts high activity at this time. Paradoxically, support for both positions is found in the present study of girls and boys from birth to 6 years of age.

Prenatal Cocaine and Neonatal Outcome: Evaluation of Dose-Response Relationship

The aim of this study was to evaluate the hypothesis that prenatal cocaine exposure would negatively affect newborn behavior. A prospective observational study of term infants recruited from the low-risk nursery used a structured, standardized interview to obtain maternal data. Cocaine exposure was determined by radioimmunoassay of the infant's meconium stool. An examiner blinded to the infant's cocaine status administered the Brazelton Neonatal Behavioral Assessment Scales. The sample was composed of 23 exposed and 29 nonexposed infants. On six of the seven Brazelton Neonatal Behavioral Assessment Scale clusters, cocaine-exposed infants performed less well than control infants, with significant differences observed for autonomic stability. In addition, a dose-response relationship was suggested. Significant negative, within-group relationships were evident in the exposed group, indicating poorer performance with increasing meconium cocaine concentration for orientation (r = -.40) and regulation of state (r = -.40). Regression model testing of the influence of meconium cocaine concentration on neurobehavioral outcomes, after controlling for significant confounders, identified a significant independent, negative effect of meconium cocaine concentration on two clusters-motor and regulation of state. In otherwise healthy full-term infants, prenatal cocaine exposure identified by quantitative analysis of cocaine concentration in meconium had a significant, independent negative association with motor and regulation of state that remained after controlling for other significant confounders. A dose-response relationship was evident.

Drug-hormone interactions on neurobehavioral responses in human neonates

Features of drug-behavioral interaction were studied in 42 healthy vaginally delivered newborns who were exposed either to local anesthesia or centrally acting opioids during labor and delivery. Each drug group consisted of 14 infants (7 males, 7 females). Results revealed that infants whose mothers received no anesthesia or only an epidural block with a local anesthetic (Marcaine) performed better on the neurobehavioral portion of testing than infants whose mothers received an epidural with narcotic sedatives (Demerol or Fentanyl). There was also an interactive effect between sex and drug group on salivary cortisol following stimulation. There were no significant effects for drug group or sex on gross measures of crying. Obstetric medication effects on newborn behavior and stress hormone changes appear to be influenced in varying degrees by drug potency, temporal factors, and sex of the infant.

Comparison of newborn circumcision pain to calcaneal heel puncture pain: is newborn circumcision pain control clinically warranted?

In newborns, elective male circumcision and calcaneal puncture for obtaining blood samples both cause pain. With elective male circumcision, dorsal penile nerve block (DPNB) is recommended for pain control, but no pain control is routinely recommended or used during calcaneal puncture. A prospective investigation was conducted to compare pain during elective circumcision (with and without DPNB) and calcaneal puncture to determine whether pain control should be used with the latter procedure. The study was conducted at a community hospital during a 4-month period. Two nurses observed newborn behavior during elective circumcision and routine calcaneal puncture and rated pain reactions by using a modified Gronigen Distress Scale. Ninety-one male newborns were circumcised without DPNB, and eight male newborns were circumcised with DPNB. Calcaneal puncture for blood samples was performed in 97 newborns (males and females). Pain scores during circumcision with and without DPNB were comparable with those during calcaneal puncture (2.1, 2.4, and 2.2, respectively). Pain control during circumcision may thus be considered, but caution should be taken that measures to prevent pain do not create new patient risk or additional pain.

Specificity of Preventative Pediatric Intervention Effects in Early Infancy

The efficacy of two contrasting short term preventative interventions administered to a heterogeneous sample of new mothers during the perinatal period was evaluated. The first was infant-centered and used the Brazelton Neonatal Behavioral Assessment Scale (NBAS) as a method of highlighting newborn behavior to new mothers. The second was mother-centered and consisted of an in-depth interview focused on the mothers' concerns about parenting. Mothers were randomized into groups and were administered intervention by experienced clinicians at 3 days in the hospital and again at 14 and 30 days at home. Effects of intervention on maternal reports of parenting stress, mother-infant interactive behavior, and infant developmental quotient were evaluated at 4 months infant age. It was hypothesized that participation in the infant-centered intervention would be related to more positive maternal and infant outcomes at 4 months. It was also expected that the impact of each intervention would be moderated by differences in maternal and infant risk and parity. Hierarchical multiple regressions controlling for risk and parity yielded no significant main effects of intervention at 4 months. However, significant interactions of intervention with parity and risk were observed, indicating that intervention was beneficial for specific groups of mothers. These data suggest that early intervention should be tailored to the needs of individual groups of mothers.

Preparing staff nurses to teach parents about newborn behavior.

The purpose of this project was to teach postpartum nurses about the many facets of newborn behavior and to help these nurses teach parents to recognize and respond to their newborn's cues, states, and behaviors. The Keys to Caregiving: Self-Instructional Video Series was used to accomplish this goal. Eighteen maternal-child nurses from a large metropolitan health sciences center completed the program. The average pre-test score was 80%; the average post-test score was 94%. Based on the pre- and post-test scores, the results demonstrate an improvement in nurses' knowledge about newborn behavior after completing the Keys to Caregiving program. The responses from staff nurses who completed the program were overwhelmingly positive.

Cocaine metabolites in the neonate: potential for toxicity.

Recent reports indicate that cocaine metabolites have biologic activity and could be toxic. To explore this possibility, two studies were initiated. The first study aimed to define the distribution of cocaine species by quantifying levels of cocaine and its metabolites norcocaine, benzoylecgonine, and benzoylnorecgonine in newborn cord blood and meconium. The second study sought to determine whether they produced a clinical effect. Compared to cord blood, meconium had a greater number of metabolites and a higher concentration of cocaine metabolites, including the previously undetectable norcocaine and benzoylnorecgonine derivatives. Benzoylecgonine was the most common species found in both sources and was usually lower in concentration in blood. An inverse relation existed between meconium benzoylecgonine levels and the serum catabolic enzyme pseudocholinesterase, implying genetic variability in cocaine metabolism. To determine whether cocaine and/or its metabolites could be linked to a distinct clinical state, a second study focusing on newborn behavior was performed with an independent large cohort of cocaine-exposed infants. Neonates with increased signs of "neuroexcitation" had benzoylecgonine and no cocaine in urine, whereas lethargic neonates had detectable urinary cocaine. These findings support the hypothesis that cocaine metabolites, especially benzoylecgonine, may play a role in altering newborn behavior and produce a clinical syndrome distinct from that related to the parent compound.

Influence of gestational age, birth weight, and asphyxia on neonatal neurobehavioral performance

The objectives of this study were to determine the influence of birth weight, gestational age, and asphyxia on neurobehavioral performance at 40 weeks conceptional age, and to demonstrate that this performance may differ in preterm high-risk infants when using low-risk preterm rather than healthy term infant norms. A cross-sectional comparative design was used to compare neurologic behavior in healthy and highrisk newborns at 40 weeks conceptional age using the Einstein Neonatal Neurobehavioral Assessment Scale. Seventy-four high-risk newborns were selected from a consecutive sample of asphyxiated, very-low-birth-weight, and small-for-gestational-age neonates. Controls did not fulfill any of the high-risk criteria and had no pre- or perinatal complications. There were 37 healthy term and 17 low-risk preterm controls. Statistically significant differences occurred between highrisk newborns and term controls for the total score ( P < .001) as well as for most individual items ( P < .05). Analysis of high-risk subgroups revealed that small-for-gestational-age and term asphyxiated newborns had the most abnormal responses. When comparing test performance between preterm high-risk and term controls, the majority of test items achieved significance ( P < .05); however, when compared to low-risk preterm controls, fewer items were abnormal, and the probability level on abnormal items was less significant than expected. This disparity in interpretation of neurobehavioral status in preterm high-risk neonates using a preterm versus term reference sample warrants further investigation. Appropriate normative standards for preterm infants require definition because it may increase the utility of the neonatal neurologic examination and its prognostic value.

The Neurobehavioral Organization of Efe (Pygmy) Infants

The neurobehavioral organization of 16 Efe Mbuti (pygmy) infants was examined over the first weeks of life using the Brazelton Neonatal Behavioral Assessment Scale. Mbuti infants are the smallest well-grown, full-term infants in the world, i.e., length and weight below the 10th percentile but ponderal index above the 50th percentile. The Efe infants are a relatively isolated population that allows for an evaluation of ethnic differences in newborn behavior; their small stature permits the examination of the relations among size, neurobehavioral organization, and morbid processes. The neurobehavioral organization of the Efe was compared with three groups of full-term infants: two full-statured, well-grown groups of infants, one African, one United States; and a group of symmetrically growth-retarded infants whose weight and length were proportionally compromised in utero. The behavioral organization of the Efe infants was found to be similar to the neurobehavior of the well-grown infants and superior to the group of growth-retarded infants. No unique neurobehavioral features were found compared with the other groups. These findings suggest that neurobehavioral organization has a universal form and that expected small size per se does not compromise infant behavior.

Short-term Effects of Feed Composition on Sleeping and Crying in Newborns

To determine whether the composition of feedings would affect newborn behavior independently of the act of feeding itself, 53 two- to three-day-old normal newborns were randomly assigned to receive an extra feeding of water, carbohydrate (lactose), or balanced formula 3 hours after their usual early morning feeding. Previous studies in adult humans and animals, and a single study in human newborns, have indicated that more sleep might be expected following the carbohydrate feed compared with the water and balanced-formula feeds because of recruitment of centrally mediated serotonergic systems. Behavioral effects were assessed for 40 minutes postfeeding by direct observation of the newborn's states (quiet, active, and indeterminate sleep; drowsiness; non-cry wakefulness; and fret/cry). Feed composition did affect behavior, and the effects were fairly specific to particular newborn states. Non-cry wakefulness and drowsiness were unrelated to the presence or type of nutrients, but they tended to occur soon after the meal in all groups. Crying was increased in water-fed newborns relative to both carbohydrate- and formula-fed newborns. Sleeping showed specific patterns of change in all three groups. Sleep duration was increased in the balanced-formula group compared with the water group throughout the observation period. Contrary to the prediction, sleeping duration in carbohydrate-fed newborns never exceeded that of formula-fed newborns; rather, it resembled that of water-fed newborns early in the postprandial period, but formula-fed newborns later. These effects could not easily be explained by potential confounding factors such as handling, volume ingested, caloric intake, or plasma glucose concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Determinants of pregnancy outcome and newborn behavior of a semirural Egyptian population

Several potential determinants of birth weight and neonatal behavioral organization, ie, maternal anthropometry, food intake (energy, protein, and plant- and animal-source foods), morbidity, and household socioeconomic status, were followed systematically in a semirural Egyptian population during greater than or equal to 6 mo of pregnancy. In early pregnancy mothers were generally normal weight to moderately overweight. Their mean energy intake, largely from plant sources, was approximately 8.37 MJ/d (2000 kcal/d) during trimesters 2 and 3. Early (3 mo) pregnancy weight and weight gain during trimesters 2 and 3 were significantly positively related to birth weight Z scores. The best predictor model examined for birth weight included early pregnancy weight, weight gain, and length of gestation (R2 = 0.45). Early pregnancy weight and maternal intake of animal-source foods were significant positive predictors of the newborn's orientation and habituation behavior, respectively. Habituation and orientation measures assess the infant's early ability to process information.

Circulating Catecholamine Concentrations in Cocaine-Exposed Neonates: A Pilot Study

Twenty newborns, 12 with prenatal exposure to cocaine and an unexposed control group of 8, were studied to determine concentrations of circulating catecholamines and their relationship to newborn behavior. Birth weight of the cocaine-exposed neonates was significantly lower than that of the control group. Gestational age, length, and head circumference of the cocaine-exposed neonates were also lower, although the differences did not reach statistical significance. Between 24 and 48 hours of age, circulating concentrations of norepinephrine, dopamine, and the catecholamine precursor dihydroxyphenylalanine were measured and behavior was assessed using the Neonatal Behavioral Assessment Scale. Mean dihydroxyphenylalanine concentrations were increased in the cocaine-exposed newborns (10.3 ng/mL vs 5.9 ng/mL, P = .055), while there was no difference between the groups in mean norepinephrine or dopamine concentrations. There was a significant negative correlation between norepinephrine concentration and orientation cluster score for the cocaine-exposed newborns (r2 = .6979, P = .005). norepinephrine concentration did not correlate with the score for any other behavioral cluster, nor did dopamine or dihydroxyphenylalanine concentration correlate with the score for any cluster. These preliminary data from a pilot study suggest that catecholamine activity is increased in cocaine-exposed newborns and may play a role in neurobehavioral disturbances associated with prenatal exposure to this drug.

Using the Brazelton Neonatal Assessment Scale to Facilitate the Parent-Infant Relationship in a Primary Care Setting

This article describes use of the Brazelton Neonatal Assessment Scale (BNAS) as an effective parent-teaching tool and demonstrates how this tool can be successfully integrated into a primary care setting. Research indicates that the BNAS can be used to enhance parent-infant bonding, to promote parents' confidence, and to intervene in potentially dysfunctional parent-infant interactions before poor parenting patterns become well established. Case studies exemplify how a clinician can use the BNAS to evaluate 37 newborn behaviors and 18 neurological reflexes, identifying the newborn's individual strengths, elucidating coping behaviors (as he or she strives to maintain control over the autonomic nervous system), illuminating his or her individual stress responses, and demonstrating which comforting techniques are most effective for that child. Further case studies illustrate how the tool can enable a clinician to identify the positive characteristics of a difficult baby, and emphasize the importance of noticing and responding appropriately to a baby's state of consciousness. The BNAS is an effective interactional exam because the clinician captures the patients' attention by interacting with their newborn. During this interaction the clinician assesses and describes the newborn's strengths and needs, and at the same time models effective interaction with the infant. Samples of the BNAS scoring protocol and a helpful parent-education handout are included.