Outcome of neonates with birth weights of less than 801 grams

The follow-up results of intensive care for 68 infants with birth weights less than 801 g treated at Stanford University Hospital were reviewed. The overall survival rate for these infants was 35%, but was 50% for those infants who had been successfully resuscitated in the delivery room and were admitted to the Intensive Care Nursery. Infants under 601 g in weight or less than 25 weeks gestation were more likely to die in the delivery room, but survival among those admitted to the Intensive Care Nursery did not depend on birth weight or gestational age. One-minute and 5-minute Apgar scores less than 5 and interstitial emphysema were associated with increased risk of neonatal death. Only two of 22 survivors (9%) were severely handicapped and another eight (36%) had remediable disabilities at 2 years of age. No infant developed hydrocephalus and only one infant had spasticity. We suggest that the low incidence of major handicaps among survivors encourages the vigorous resuscitation of infants weighing less than 801 g at birth, yet strategies must be developed that will minimize both prolonged dying and the cost of intensive care for nonviable infants.     

Status of infants at birth and risk for adverse neonatal events and long-term sequelae: a study in low birth weight infants

We evaluated the relationship of infant status at birth to neonatal morbidity and long-term development in 246 low birth weight infants (600 to 1750 gm). Nineteen percent of infants had 1-minute Apgar scores of less than or equal to 3, and 8% had an umbilical artery pH of less than or equal to 7.2. Acidosis was associated with an increased risk of grade 3 to 4 intracranial hemorrhage (odds ratio = 3.3). Low 1-minute Apgar score was associated with an increased risk of death (odds ratio = 4.8). Grade 3 to 4 intracranial hemorrhage was a strong risk factor for cerebral palsy among survivors (odds ratio = 16.1), as was low 1-minute Apgar score (odds ratio = 2.9). Only 15% of cases of cerebral palsy in this study were associated with acidosis at birth.     

Positive changes among very low birth weight infant Apgar scores that are associated with the Neonatal Resuscitation Program in Illinois.

OBJECTIVE: The American Academy of Pediatrics and American Heart Association sponsored Neonatal Resuscitation Program (NRP) was started in Illinois 1987 to standardize knowledge and skills for successful resuscitation to decrease newborn morbidity and mortality. This study evaluated the hypothesis that the statewide NRP in Illinois hospitals was associated with positive outcomes in the Apgar scores among very low birth weight newborns. STUDY DESIGN: A retrospective design was used to compare the (a) different rates of lower (0-6) and higher (7-10) 1- and 5-minute Apgar scores and (b) positive change from a lower 1-minute to a higher 5-minute Apgar score before and after NRP was started. Analyses included maternal characteristics, birth weight groups (grams: 500-749, 750-999, 1000-1249, 1250-1499), and hospital levels (I, II, III). RESULTS: A significantly higher proportion of infants had a higher 1-minute and a higher 5-minute Apgar score after NRP, overall, for Level II and II+ hospitals and for each weight group. Logistic regression indicated that newborns with low 1-minute Apgar scores were 81% more likely to have a higher 5-minute Apgar score after NRP. CONCLUSION: Significant improvement in Apgar score occurred after NRP. Empirical support is demonstrated for the clinical effectiveness of NRP instruction in Illinois hospitals.     

Correlating head-to-body delivery intervals with neonatal depression in vaginal births that result in permanent brachial plexus injury

OBJECTIVE: The purpose of this study was to evaluate which variables predict neonatal depression in vaginal deliveries that result in permanent brachial plexus injury. STUDY DESIGN: With the use of a data set of litigated vaginal deliveries (n = 103 deliveries) from 1978 through 1999 that resulted in permanent brachial plexus injury, detailed delivery and neonatal and pediatric information was obtained by chart review. Neonatal depression was defined as a 5-minute Apgar score of <7. Data that were extrapolated from neonates with low Apgar scores at 5 minutes were compared with neonates with Apgar scores of > or =7 with the use of the Fisher exact test, chi(2) test, or one-way analysis of variance; a two-tailed probability value of <.05 was considered significant. RESULTS: Nine of 89 neonates (10%) had low 5-minute Apgar scores. Head-to-body delivery intervals (available for 36 deliveries) were significantly longer in neonates with 5-minute Apgar scores of <7 vs > or =7 (294 +/- 68 seconds vs 147 +/- 82 seconds, P <.001). Differences in other clinical variables (ie, maternal weight, gestational age, diabetes mellitus, parity, birth weight, and sex) were not significant. None of the infants in this data set, which includes those infants with neonatal depression) died or had long-term asphyxia-related sequelae in the form of speech impediments, seizures, cerebral palsy, coma, or organ dysfunction. CONCLUSION: The head-to-body delivery interval was the only significant factor in the prediction of 5-minute Apgar score of <7 in a data set of deliveries that resulted in permanent brachial plexus injury. Despite extended times (< or =6 minutes) on the perineum that resulted in a higher reduced Apgar score rate, there was no asphyxia-related morbidity.     

Risk factors for early death among extremely low-birth-weight infants

OBJECTIVE: The purposes of this study were to compare the clinical characteristics of extremely low birth-weight infants (501-1000 g birth weight) who die early (<12 hours of age) with those of infants who die >12 hours after birth and infants who survive to neonatal intensive care unit discharge and to develop a model of risk for early death. STUDY DESIGN: Perinatal data were prospectively collected on 5986 infants in the 12 participating centers of the National Institute of Child Health and Human Development Neonatal Research Network from March 1993 through December 1997. Maternal and neonatal characteristics of infants who died early were compared with infants who survived and infants who died beyond 12 hours of age. A model for risk for early death was developed by logistic regression analysis, with results expressed as odds ratio with 95% CI. RESULTS: Mothers of infants who died early were more likely to be delivered in an inborn setting and experience labor and were less likely to have hypertension or preeclampsia, to receive antenatal corticosteroids, or to be delivered by cesarean birth than mothers of infants who died >12 hours after birth or infants who survived. Infants who died early were more likely to have lower Apgar scores and lower gestational age/birth weight and were less likely to be intubated at birth and to receive mechanical ventilation and surfactant therapy than infants who died >12 hours after birth or infants who survived. Greater risk for early death versus survival to neonatal intensive care unit discharge was associated with the lack of surfactant administration (odds ratio, 8.6; 95% CI, 6.3-11.9), lack of delivery room intubation (odds ratio, 5.3; 95% CI, 3.5-8.1), lack of antenatal corticosteroid use (odds ratio, 2.3; 95% CI, 1.6-3.2), lower 1-minute Apgar score (odds ratio, 2.0; 95% CI, 1.8-2.2), male sex (odds ratio, 1.7; 95% CI, 1.3-2.3), multiple gestation (odds ratio, 1.7; 95% CI, 1.2-2.5), no tocolytics (odds ratio, 1.7; 95% CI, 1.2-2.3), lower gestational age per week (odds ratio, 1.4; 95% CI, 1.3-1.6), and lower birth weight per 50 g (95% CI, 1.2-1.4). CONCLUSION: Early death (<12 hours of age) among extremely low-birth-weight infants may reflect an assessment of non-viability by obstetricians and neonatologists.     

Acid-base status at birth and neurodevelopmental outcome at four and one-half years

Two hundred thirty term infants with measured acid-base status in umbilical arterial blood at birth were selected from 1210 consecutive deliveries for detailed neurodevelopmental follow-up at age 4 1/2 years; 203 were examined. Cutoff points approximately 1 SD from the mean (pH less than or equal to 7.10; base deficit greater than 12 mmol/L) were used to define acidosis. No statistically significant associations between acidosis and developmental outcome were found. The highest proportion of unimpaired children was found among those who were most severely acidotic at birth (pH less than or equal to 7.04; 2 SD below mean), but this finding was not statistically significant. These findings suggest that the ability of the fetus to produce an acidosis in response to the stress of labor may be beneficial to long-term outcome. The 10 nonacidotic babies with 1-minute Apgar scores of less than or equal to 3 showed statistically significant deficits in some areas. Coincident acidosis was not associated with a worse outcome for infants with low Apgar scores.     

Anorexia nervosa, bulimia, and pregnancy

Of 74 women previously treated for anorexia nervosa or bulimia, 15 had conceived 23 pregnancies when assessed at follow-up. The status of the eating disorder, course of pregnancy and delivery, infant health, and postpartum adjustment are described. Women in whom eating disorders were in remission at conception had greater maternal weight gain and babies with higher birth weights and 5-minute Apgar scores than women who conceived while they still had symptoms of restricting anorexia nervosa or bulimia. Women who had symptoms of eating disorders at conception also had continuance or worsening of these symptoms during pregnancy and the postpartum year. We recommend delay of pregnancy until the eating disorder is truly in remission.     

Comparison of umbilical artery pH and 5-minute Apgar score in the low-birth-weight and very-low-birth-weight infant

The division between "normal" and low Apgar scores is based largely on data obtained from term newborns and may not apply to the premature infant. Umbilical artery pH has been suggested as a better indicator of intrapartum asphyxia. We examined the charts of 558 infants with birth weights less than or equal to 2500 gm with respect to umbilical artery pH, 5-minute Apgar scores, and birth weight percentiles. A positive correlation between birth weight and 5-minute Apgar score was noted. No such relationship existed between birth weight and umbilical artery pH. Within birth weight groups, small-for-gestational-age infants have higher Apgar scores and lower umbilical artery pH values than their appropriate-for-gestational age counterparts.     

Outcome of extremely-low-birth-weight infants at highest risk: gestational age < or =24 weeks, birth weight < or =750 g, and 1-minute Apgar < or =3

OBJECTIVE: The purpose of this study was to evaluate neurodevelopmental outcome in extremely-low-birth-weight (ELBW) infants, all of whom had 3 characteristics: gestational age (GA) < or =24 weeks, birth weight < or =750 g, and 1-minute Apgar score < or =3. STUDY DESIGN: Surviving infants were evaluated at 18 to 22 months' corrected age with a neurologic examination and the Bayley II Mental and Psychomotor Developmental Index (MDI and PDI). RESULTS: Between 1993 and 1999, 1016 infants had GA < or =24 weeks, birth weight < or =750 g, and 1-minute Apgar score < or =3. Of 246 survivors, 30% had cerebral palsy (CP), 5% had hearing impairment, and 2% were blind. MDI was > or =85 in 33% and < 70 in 46% of infants, while PDI was > or =85 in 41% and < 70 in 36% infants. Predictors of MDI < 70 were grade III-IV ICH, cystic periventricular leukomalacia (PVL), male gender, black race, and Medicaid insurance. Two-parent household was associated with an MDI >70. Predictors of PDI < 70 were grade III-IV ICH, PVL, steroids for bronchopulmonary dysplasia (BPD), and Medicaid insurance. CP was associated with grade III-IV ICH and PVL. CONCLUSION: Perinatologists and neonatologists should be aware of the risk of morbidity and mortality in this high-risk ELBW group.     

Factors affecting survival in infants weighing 750 g or less

OBJECTIVE: To assess which factors independently affect survival in infants weighing 750g or less. STUDY DESIGN: We reviewed the obstetric, neonatal, and placental pathology information of all non-malformed neonates with birth weight of 750g or less from January 1998 to December 2002. Logistic regression analysis was used to control for the effect of confounding variables. A P<0.05 was considered significant. RESULTS: Fifty nine neonates fulfilled the inclusion criteria; 30 (51%) survived the perinatal period. Surviving neonates were more frequently born after steroid administration (P=0.03) and from indicated delivery (P=0.01), had greater birth weight (P=0.001), gestational age at delivery (P<0.001), and 5-min Apgar scores of 7 or more (P=0.04) than those who died. There were no significant differences in placental pathology between survivors and neonates who died. Stepwise logistic regression analysis showed that gestational age (P=0.01), birth weight (P=0.004), female sex (P=0.03), 5-min Apgar score (0.026), and steroid administration (P=0.04) were independent predictors of survival. Cumulatively these five predictors explained 69% of neonatal survival. CONCLUSIONS: The predictors of survival among micropremies are the same as those reported for older preterm neonates. The type of preterm delivery (spontaneous versus indicated) and placental pathology do not independently affect survival.     

Apgar scores and cognitive performance at 17 years of age

The association between low Apgar scores (7 or less) at 1 and 5 minutes and cognitive performance in late adolescence was assessed. A 17-year follow-up of 1942 subjects was performed. The intelligence test scores at 17 years of age were matched with 1- and 5-minutes Apgar scores. A multiple linear regression analysis was used to control for the possible confounding effect of perinatal factors (birth weight, gestational age, serum bilirubin levels, birth order) and demographic characteristics (ethnic origin, paternal education, social class). The sensitivity and positive predictive value of a low 1-minute Apgar score were 8 and 8% and of a low 5-minute Apgar score 1.5 and 5%, respectively. Low Apgar scores are poorly correlated with long-term intellectual outcome.     

Low 5-minute Apgar score: a population-based register study of 1 million term births.

OBJECTIVE: To determine the rate of 5-minute Apgar scores below 7 in term infants (at least 37 weeks) in Sweden during 1988-1997, evaluate the influence of obstetric risk factors on low 5-minute Apgar scores, and to study the infant prognosis regarding infant mortality, neonatal neurologic morbidity, and outcome. METHODS: Data were collected from the Swedish Medical Birth Registry 1988-1997, and the National Hospital Discharge Registry. Odds ratios (OR) and risk ratios were calculated. RESULTS: Among 1,028,705 term newborns, 7787 (0.76%) had 5-minute Apgar scores below 7. The annual rate of low Apgar scores decreased from 0.77% in 1988 to 0.63% in 1992, but thereafter increased to 0.82% in 1998. The highest OR was found for vaginal breech delivery (OR 6.7), birth weights above 5 kg (OR 6.3), and second born twins (OR 4.1). Primiparity, maternal age, smoking, post-date pregnancy, epidural analgesia, male infant gender, and being born at night, were also significant risk factors for Apgar below 7 at 5 minutes. The infant mortality rate was 48 per 1000 (OR 14.4), and the ORs were 31.4 for a diagnosis with cerebral palsy, 7.9 for epilepsy, and 9.5 for mental retardation. CONCLUSION: Several obstetric risk factors are associated with low 5-minute Apgar score in term infants. Mortality and the risk of severe neurologic morbidity are increased in these infants.     

A persistent clinical problem: profile of the term infant with significant respiratory complications.

A group of 72 term infants with significant respiratory complications were compared with 11,428 term infants delivered during the same time period and without respiratory morbidity. Compared with controls, the study group had a higher incidence of postdatism (36 versus 7%), intrauterine growth retardation (33 versus 8%), meconium-stained amniotic fluid (AF) (90 versus 9%), fetal heart rate (FHR) abnormalities upon admission to labor and delivery (58 versus 7%), and low 5-minute Apgar scores (46 versus 1.4%). Even in the presence of normal intrapartum FHR and 5-minute Apgar scores, infants with meconium-stained AF had an incidence of respiratory complications 100 times higher than those with clear AF. Of infants with a low 5-minute Apgar score at birth, only 20% went on to develop respiratory complications. The remaining 80% had a significantly lower incidence of postdatism, intrauterine growth retardation, and meconium-stained AF.     

Antenatal and Intrapartum Events Influencing Outcome in Very Low Birth-Weight Infants

The influence of antenatal and intrapartum events and the route of delivery on Apgar scores and short-term outcome was studied in 359 singleton very low birth-weight infants who were resuscitated adequately at birth and had no lethal congenital anomalies. When stratified according to gestation the occurrence of antepartum haemorrhage, pregnancy-induced hypertension and amnionitis had no influence on the outcome while cord prolapse in infants less than 26 weeks resulted in 100% mortality. Prolonged rupture of membranes significantly improved the chances of their survival. The route of delivery did not influence survival, but greater numbers of babies between 27 and 30 weeks delivered by the breech had lower Apgar scores both at 1 and 5 minutes. Survival was dependent on gestational age and the condition at birth among this group of very low birth-weight infants.     

Early discharge of low birthweight infants as a hospital policy

All 123 infants with birthweights less than or equal to 2000 g born at a private institution between February 1, 1987, and January 31, 1988, were eligible for early discharge if they met the following criteria: weight about 1800 g, medically stable, feeding well by nipple, satisfactory weight gain, thermostability, and parents and home prepared. Forty-one of 48 (85.4%) infants who satisfied these criteria were discharged at birthweights less than 2100 g. None of the 35 infants for whom follow-up was possible were rehospitalized, had a serious illness, or died as a result of the policy. The policy was universally accepted by the staff. Such a policy has the potential to unite babies and families sooner, promote the mental health of the families, save medical dollars, and make the medical resources of newborn intensive care units available for critically ill infants.     

Obstetric antecedents to apparent stillbirth (Apgar score zero at 1 minute only)

OBJECTIVE: To identify antecedent risk factors for the delivery of an infant with an Apgar score of 0 at 1 minute who is subsequently successfully resuscitated. METHODS: Infants born between January 1986 and February 1999 with 1-minute Apgar score of 0 followed by 5-minute Apgar score above 0 were studied. Each eligible infant was randomly matched with two control infants, born in the same year, with 1-minute Apgar score greater than 0. Hospital records of their mothers were reviewed. The variables were compared between the groups by univariate analysis. Those factors demonstrating significant differences were then analyzed by logistic regression. P <.05 was considered statistically significant. RESULTS: Seventy-four of 81,603 infants (0.9:1000 births) born with an Apgar score of 0 at 1 minute only were compared with 148 control babies. Univariate analysis revealed significant differences between study and control group regarding: gestational age, abruptio placentae, preterm premature rupture of membranes, chorioamnionitis, preeclampsia, small-for-gestational age, male gender, bradycardia, and abnormal fetal heart rate (FHR) other than bradycardia, respectively. Logistic regression of these factors found gestational age, bradycardia, and abnormal FHR to be independent risk factors for the delivery of an apparent stillborn infant. After exclusion of FHR criteria, logistic regression found gestational age (odds ratio [OR] 0.8 per week), male gender (OR 2.5), preeclampsia (OR 3.9), and abruptio placentae (OR 13.6) to be independent risk factors for the delivery of an apparent stillborn infant. CONCLUSION: Preterm birth, male gender, preeclampsia, and abruptio placentae are independently associated with an increased risk of apparent stillbirth.     

Obstetric variables predicting survival of the immature newborn (less than or equal to 1000 gm): a five-year experience at a single perinatal center

The immature neonate constitutes less than 3% of total births and yet accounts for almost 50% of all perinatal deaths. In a 5-year period, 476 consecutive live and inborn neonates weighing less than or equal to 1000 gm were studied. The purpose of this study was to describe our experience with these pregnancies and determine the obstetric predictors of survival. Statistical methods of univariate and multivariate analysis were used. Survival was defined as the discharge home of an alive infant. The overall survival rate without exclusions was 40.3%. The following variables were most significant and accurately predicted survivors in 76.2% and nonsurvivors in 69.2% of cases: a combination of birth weight, 5-minute Apgar score, gestational age, cervical dilatation on admission, sex, a more recent study time interval, and race. Of the factors studied, the following were directly related to advancing gestational age and birth weight: higher Apgar scores at 1 and 5 minutes, increased operative delivery rate, and increased frequency of tocolysis and glucocorticoid usage; of these factors, only the 5-minute Apgar score remained statistically significant, when controlling for gestational age and birth weight by multivariate analysis.     

Neurobehavioral assessment predicts differential outcome between VLBW and ELBW preterm infants.

OBJECTIVE: To evaluate the impact of birth weight on development of very low birth weight (VLBW) infants using the Neurobehavioral Assessment of the Preterm Infant (NAPI) before hospital discharge, and to show the relation to follow-up outcomes at 12, 18 and 30 months of age. STUDY DESIGN: In total, 113 preterm infants were assessed with the NAPI at 36 weeks postmenstrual age. Later, neurodevelopment was examined using the Bayley Infant Neurodevelopmental Screener (BINS) at 12 months and the Bayley Scales of Infant Development, at 18 and 30 months. The cohort was divided into two groups, based on birth weight, extremely low birth weight (ELBW) (<1000 g) and VLBW (1000 to 1500 g). RESULTS: ELBW infants showed significantly lower NAPI scores compared with VLBW infants at 36 weeks. The predischarge NAPI scores correlated with the 12, 18 and 30 months scores when the ELBW infants continue to have lower performance than the VLBW infants. In all, 14 infants developed cerebral palsy. These infants had significantly lower NAPI, BINS and Bayley scores compared with all other preterm infants. CONCLUSION: NAPI before discharge provides clinically meaningful information related to later neurodevelopmental outcome.     

Outcomes of macrosomic infants in a nurse-midwifery serivce

The purpose of this study was to compare outcomes of term infants of average birth weight with outcomes of large infants in a nurse-midwifery service. A retrospective study design was used. Data were retrieved from a computer data base that contained information from a data form routinely completed for all births. Subjects were women cared for by the nurse-midwives including those for whom the birth was conducted by a physician. The final n study population was 2,228; 322 (14.5%) of the infants weighed 4,000 g or more. Women who delivered large infants had a significantly higher prepregnant body mass index and pregnancy weight gain. Shoulder dystocia occurred more often in large infants; however, newborn intensive care unit admission rates did not differ between the average birth weight and the large infants. Apgar scores at 1 and 5 minutes were significantly lower for infants weighing ≥ 4,500 g compared to those with birth weights of 2,500–3,999 g and those 4,000–4,449 g; however, these differences were not clinically significant. A trend for fewer occurrences of shoulder dystocia in the side-lying birth position was observed. Logistic regression predicting poor Apgar scores (< 7) showed parity as a protective factor and increased gestational age and higher maternal body mass index as predictive of low Apgar scores. Large infants had birth outcomes comparable to those reported by others in the medical literature, suggesting that nurse-midwifery management, including consultation with physician colleagues, can be appropriate and safe.     

Influence of chorioamnionitis on developmental outcome in very low birth weight infants.

OBJECTIVE: To determine the effect of exposure to chorioamnionitis on developmental outcome in very low birth weight (VLBW) infants. METHODS: Five hundred four maternal charts (97% of all VLBW infants delivered from 1990 to 1994) were reviewed. A historical cohort study of the 330 infants delivered secondary to preterm premature rupture of membranes or preterm labor was performed. Case subjects (71) were delivered of mothers with chorioamnionitis by clinical criteria; control subjects (259) were delivered of mothers without chorioamnionitis. Bayley index scores at 7 months' corrected age and special care nursery outcomes were compared. One hundred seventy-three subjects were necessary to reject the two-sided null hypothesis with 80% power with a difference in mean Bayley index scores of at least 8. RESULTS: Neonatal sepsis (8.5% compared with 1.9%; odds ratio [OR] = 4.7, 95% confidence interval [CI] 1.4, 15.9, P = .015) and a low 5-minute Apgar (72% compared with 55%; OR = 2.1, CI 1.2, 3.8, P = .012) occurred more frequently in the chorioamnionitis group. One hundred eighty-seven (68%) of 273 surviving neonates had follow-up. Cases and controls were similar in mean Bayley mental developmental index (91.2 compared with 91.8, P = .84), Bayley psychomotor developmental index (89.8 compared with 89.1, P = .82), and number of infants developmentally delayed. Duration of exposure to chorioamnionitis did not affect neonatal outcome. CONCLUSION: Despite higher rates of sepsis and low Apgar scores, no difference in outcome at 7 months of corrected age was detected in VLBW infants exposed to chorioamnionitis. Contemporary neonatal management may reduce the adverse effects of this exposure.