Advances in Neonatal Infections.

Despite continued advances and developments in neonatal medicine, neonatal sepsis is the third leading cause of neonatal mortality and a major public health problem, especially in developing countries. Sepsis accounts for mortality for almost 50% of global children under 5 years of age.Over the past 50 years, there have been many advances in the diagnosis, prevention, and treatment of neonatal infections. The diagnostic advances include better culture techniques that permit more rapid confirmation of the diagnosis, advent of polymerase chain reaction (PCR) to rapidly diagnose viral infections, use of biologic markers indicating evidence of infection, and a better understanding of immunoglobulin markers of infection. From a therapeutic stand point, there have been a variety of antibiotics, antifungals, and antiviral agents, better approaches to prevent sepsis, specific immunotherapy, for example, respiratory syncytial virus (RSV); bundled approach to prevention of deep-line infection and better antibiotic stewardship, leading to earlier discontinuation of antibiotic therapy.Hand hygiene remains the benchmark and gold standard for late-onset sepsis prevention. The challenge has been that each decade, newer resistant bacteria dominate as the cause of sepsis and newer viruses emerge, for example, human immunodeficiency virus, zika virus, and novel coronavirus disease 2019.Future treatment options might include stem cell therapy, other antimicrobial protein and peptides, and targeting of pattern recognition receptors in an effort to prevent and/or treat sepsis in this vulnerable population. Also, the microbiome of premature infants has a smaller proportion of beneficial bacteria and higher numbers of pathogenic bacteria compared with term infants, likely owing to higher frequencies of cesarean sections, antibiotic use, exposure to the hospital environment, and feeding nonhuman milk products. Modifying the microbiome with more mother's milk and shorter duration of antibiotics in noninfected babies should be a goal. KEY POINTS: · Neonatal sepsis remains a leading cause of mortality.. · Challenges include bacterial resistance and newer viruses.. · Future treatments may include newer antibiotics/antivirals and stem cell therapy..

The ongoing quandary of defining the standard of care for neonates.

UNLABELLED: Despite extensive use of the term 'standard of care' (SOC), there is no such medical definition. How are neonatal therapies accepted as SOC with huge centre-to-centre variation? What defines SOC? We will consider paths to acceptance of multiple therapies (antenatal corticosteroids, preventing GBS, others). We conclude single-centre trials drive care, but are not consistently predictive for multicentre trials. Innovation/quality improvement initiatives also alter care, despite strong evidence practice changes take time. Furthermore, there are powerful medico-legal implications if a therapy is designated SOC. CONCLUSION: Defining SOC is a quandary with more legal implications than medical, but what's most critical is keeping current in a rapidly changing field.

Death or neurodevelopmental impairment at 18 to 22 months corrected age in a randomized trial of early dexamethasone to prevent death or chronic lung disease in extremely low birth weight infants.

OBJECTIVE: To evaluate the incidence of death or neurodevelopmental impairment (NDI) at 18-22 months corrected age in subjects enrolled in a trial of early dexamethasone treatment to prevent death or chronic lung disease in extremely low birth weight infants. STUDY DESIGN: Evaluation of infants at 18-22 months corrected age included anthropomorphic measurements, a standard neurological examination, and the Bayley Scales of Infant Development-II, including the Mental Developmental Index and the Psychomotor Developmental Index. NDI was defined as moderate or severe cerebral palsy, Mental Developmental Index or Psychomotor Developmental Index <70, blindness, or hearing impairment. RESULTS: Death or NDI at 18-22 months corrected age was similar in the dexamethasone and placebo groups (65% vs 66%, P = .99 among those with known outcome). The proportion of survivors with NDI was also similar, as were mean values for weight, length, and head circumference and the proportion of infants with poor growth (50% vs 41%, P = .42 for weight less than 10th percentile); 49% of infants in the placebo group received treatment with corticosteroid compared with 32% in the dexamethasone group (P = .02). CONCLUSION: The risk of death or NDI and rate of poor growth were high but similar in the dexamethasone and placebo groups. The lack of a discernible effect of early dexamethasone on neurodevelopmental outcome may be due to frequent clinical corticosteroid use in the placebo group.

Aggressive vs. conservative phototherapy for infants with extremely low birth weight.

BACKGROUND: It is unclear whether aggressive phototherapy to prevent neurotoxic effects of bilirubin benefits or harms infants with extremely low birth weight (1000 g or less). METHODS: We randomly assigned 1974 infants with extremely low birth weight at 12 to 36 hours of age to undergo either aggressive or conservative phototherapy. The primary outcome was a composite of death or neurodevelopmental impairment determined for 91% of the infants by investigators who were unaware of the treatment assignments. RESULTS: Aggressive phototherapy, as compared with conservative phototherapy, significantly reduced the mean peak serum bilirubin level (7.0 vs. 9.8 mg per deciliter [120 vs. 168 micromol per liter], P<0.01) but not the rate of the primary outcome (52% vs. 55%; relative risk, 0.94; 95% confidence interval [CI], 0.87 to 1.02; P=0.15). Aggressive phototherapy did reduce rates of neurodevelopmental impairment (26%, vs. 30% for conservative phototherapy; relative risk, 0.86; 95% CI, 0.74 to 0.99). Rates of death in the aggressive-phototherapy and conservative-phototherapy groups were 24% and 23%, respectively (relative risk, 1.05; 95% CI, 0.90 to 1.22). In preplanned subgroup analyses, the rates of death were 13% with aggressive phototherapy and 14% with conservative phototherapy for infants with a birth weight of 751 to 1000 g and 39% and 34%, respectively (relative risk, 1.13; 95% CI, 0.96 to 1.34), for infants with a birth weight of 501 to 750 g. CONCLUSIONS: Aggressive phototherapy did not significantly reduce the rate of death or neurodevelopmental impairment. The rate of neurodevelopmental impairment alone was significantly reduced with aggressive phototherapy. This reduction may be offset by an increase in mortality among infants weighing 501 to 750 g at birth. (ClinicalTrials.gov number, NCT00114543.)

Cytokines and neurodevelopmental outcomes in extremely low birth weight infants.

OBJECTIVE: To determine if selected pro-inflammatory and anti-inflammatory cytokines and/or mediators of inflammation reported to be related to the development of cerebral palsy (CP) predict neurodevelopmental outcome in extremely low birth weight infants. STUDY DESIGN: Infants with birth weights ≤1000 g (n = 1067) had blood samples collected at birth and on days 3 ± 1, 7 ± 1, 14 ± 3, and 21 ± 3 to examine the association between cytokines and neurodevelopmental outcomes. The analyses were focused on 5 cytokines (interleukin [IL] 1ß; IL-8; tumor necrosis factor-α; regulated upon activation, normal T-cell expressed, and secreted (RANTES); and IL-2) reported to be most predictive of CP in term and late preterm infants. RESULTS: IL-8 was higher on days 0-4 and subsequently in infants who developed CP compared with infants who did not develop CP in both unadjusted and adjusted analyses. Other cytokines (IL-12, IL-17, tumor necrosis factor-ß, soluble IL rα, macrophage inflammatory protein 1ß) were found to be altered on days 0-4 in infants who developed CP. CONCLUSIONS: CP in former preterm infants may, in part, have a late perinatal and/or early neonatal inflammatory origin.

Association of antenatal corticosteroids with mortality and neurodevelopmental outcomes among infants born at 22 to 25 weeks' gestation.

CONTEXT: Current guidelines, initially published in 1995, recommend antenatal corticosteroids for mothers with preterm labor from 24 to 34 weeks' gestational age, but not before 24 weeks due to lack of data. However, many infants born before 24 weeks' gestation are provided intensive care. OBJECTIVE: To determine if use of antenatal corticosteroids is associated with improvement in major outcomes for infants born at 22 and 23 weeks' gestation. DESIGN, SETTING, AND PARTICIPANTS: Cohort study of data collected prospectively on inborn infants with a birth weight between 401 g and 1000 g (N = 10,541) born at 22 to 25 weeks' gestation between January 1, 1993, and December 31, 2009, at 23 academic perinatal centers in the United States. Certified examiners unaware of exposure to antenatal corticosteroids performed follow-up examinations on 4924 (86.5%) of the infants born between 1993 and 2008 who survived to 18 to 22 months. Logistic regression models generated adjusted odds ratios (AORs), controlling for maternal and neonatal variables. MAIN OUTCOME MEASURES: Mortality and neurodevelopmental impairment at 18 to 22 months' corrected age. RESULTS: Death or neurodevelopmental impairment at 18 to 22 months was significantly lower for infants who had been exposed to antenatal corticosteroids and were born at 23 weeks' gestation (83.4% with exposure to antenatal corticosteroids vs 90.5% without exposure; AOR, 0.58 [95% CI, 0.42-0.80]), at 24 weeks' gestation (68.4% with exposure to antenatal corticosteroids vs 80.3% without exposure; AOR, 0.62 [95% CI, 0.49-0.78]), and at 25 weeks' gestation (52.7% with exposure to antenatal corticosteroids vs 67.9% without exposure; AOR, 0.61 [95% CI, 0.50-0.74]) but not in those infants born at 22 weeks' gestation (90.2% with exposure to antenatal corticosteroids vs 93.1% without exposure; AOR, 0.80 [95% CI, 0.29-2.21]). If the mothers had received antenatal corticosteroids, the following events occurred significantly less in infants born at 23, 24, and 25 weeks' gestation: death by 18 to 22 months; hospital death; death, intraventricular hemorrhage, or periventricular leukomalacia; and death or necrotizing enterocolitis. For infants born at 22 weeks' gestation, the only outcome that occurred significantly less was death or necrotizing enterocolitis (73.5% with exposure to antenatal corticosteroids vs 84.5% without exposure; AOR, 0.54 [95% CI, 0.30-0.97]). CONCLUSION: Among infants born at 23 to 25 weeks' gestation, antenatal exposure to corticosteroids compared with nonexposure was associated with a lower rate of death or neurodevelopmental impairment at 18 to 22 months.

Whole-body hypothermia for neonates with hypoxic-ischemic encephalopathy.

BACKGROUND: Hypothermia is protective against brain injury after asphyxiation in animal models. However, the safety and effectiveness of hypothermia in term infants with encephalopathy is uncertain. METHODS: We conducted a randomized trial of hypothermia in infants with a gestational age of at least 36 weeks who were admitted to the hospital at or before six hours of age with either severe acidosis or perinatal complications and resuscitation at birth and who had moderate or severe encephalopathy. Infants were randomly assigned to usual care (control group) or whole-body cooling to an esophageal temperature of 33.5 degrees C for 72 hours, followed by slow rewarming (hypothermia group). Neurodevelopmental outcome was assessed at 18 to 22 months of age. The primary outcome was a combined end point of death or moderate or severe disability. RESULTS: Of 239 eligible infants, 102 were assigned to the hypothermia group and 106 to the control group. Adverse events were similar in the two groups during the 72 hours of cooling. Primary outcome data were available for 205 infants. Death or moderate or severe disability occurred in 45 of 102 infants (44 percent) in the hypothermia group and 64 of 103 infants (62 percent) in the control group (risk ratio, 0.72; 95 percent confidence interval, 0.54 to 0.95; P=0.01). Twenty-four infants (24 percent) in the hypothermia group and 38 (37 percent) in the control group died (risk ratio, 0.68; 95 percent confidence interval, 0.44 to 1.05; P=0.08). There was no increase in major disability among survivors; the rate of cerebral palsy was 15 of 77 (19 percent) in the hypothermia group as compared with 19 of 64 (30 percent) in the control group (risk ratio, 0.68; 95 percent confidence interval, 0.38 to 1.22; P=0.20). CONCLUSIONS: Whole-body hypothermia reduces the risk of death or disability in infants with moderate or severe hypoxic-ischemic encephalopathy.

Changes in pathogens causing early-onset sepsis in very-low-birth-weight infants.

BACKGROUND: It is uncertain whether the rates and causes of early-onset sepsis (that occurring within 72 hours after birth) among very-low-birth-weight infants have changed in recent years, since antibiotics have begun to be used more widely during labor and delivery. METHODS: We studied 5447 very-low-birth-weight infants (those weighing between 401 and 1500 g) born at centers of the Neonatal Research Network of the National Institute of Child Health and Human Development between 1998 and 2000 who had at least one blood culture in the first three days of life and compared them with 7606 very-low-birth-weight infants born at centers in the network between 1991 and 1993. RESULTS: Early-onset sepsis (as confirmed by positive blood cultures) was present in 84 infants in the more recent birth cohort (1.5 percent). As compared with the earlier birth cohort, there was a marked reduction in group B streptococcal sepsis (from 5.9 to 1.7 per 1000 live births of infants weighing 401 to 1500 g, P<0.001) and an increase in Escherichia coli sepsis (from 3.2 to 6.8 per 1000 live births, P=0.004); the overall rate of early-onset sepsis was not significantly changed. Most E. coli isolates from the recent birth cohort (85 percent) were resistant to ampicillin, and mothers of infants with ampicillin-resistant E. coli infections were more likely to have received intrapartum ampicillin than were those with ampicillin-sensitive strains (26 of 28 with sensitivity data vs. 1 of 5, P=0.01). Infants with early-onset sepsis were more likely to die than uninfected infants (37 percent vs. 13 percent, P<0.001), especially if they were infected with gram-negative organisms. CONCLUSIONS: Early-onset sepsis remains an uncommon but potentially lethal problem among very-low-birth-weight infants. The change in pathogens over time from predominantly gram-positive to predominantly gram-negative requires confirmation by ongoing surveillance.

Trends in neonatal morbidity and mortality for very low birthweight infants.

OBJECTIVE: To document the mortality and morbidity of infants weighing 501-1500 g at birth according to gestational age, birthweight, and sex. STUDY DESIGN: Prospective collection of perinatal events and neonatal course to 120 days of life, discharge, or death from January 1990 through December 2002 for infants born at 16 participating centers of the National Institute of Child Health & Human Development Neonatal Research Network. RESULTS: Compared with 1995-1996, for 1997-2002 the survival of infants with birthweight of 501-1500 g increased by 1 percentage point (from 84% to 85%). Survival without major neonatal morbidity remained static, at 70%; this includes bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), and necrotizing enterocolitis (NEC). Survival increased for multiple births (26%, up from 22%), antenatal corticosteroid use (79%, up from 71%), and maternal antibiotics (70%, up from 62%) (P < .05). From 1997 to 2002, birthweight-specific survival was 55% for infants weighing 501-750 g, 88% for 751-1000 g, 94% for 1001-1250 g, and 96% for 1251-1500 g. More females survived. The incidence of NEC (7%), severe IVH (12%), and late-onset septicemia (22%) remained essentially unchanged, but BPD decreased slightly, from 23% to 22%. The use of postnatal corticosteroids declined from 20% in 1997-2000 to 12% in 2001-2002. Growth failure (weight <10th percentile) at 36 weeks' postmenstrual age decreased from 97% in 1995-1996 to 91% in 1997-2002. CONCLUSION: There have been no significant increases in survival without neonatal and long-term morbidity among VLBW infants between 1997 and 2002. We speculate that to improve survival without morbidity requires determining, disseminating, and applying best practices using therapies currently available, and also identifying new strategies and interventions.

Short- and long-term consequences of hypotension in ELBW infants.

BACKGROUND: Hypotension affects close to half of all ELBW infants, yet an agreement on its definition is still lacking. Despite the fact that neonatal hypotension may be a risk factor for neurologic impairment, there is a paucity of data on the impact of low blood pressure (BP) in extremely low birth weight (ELBW) infants weighing below 1000 g on neuro-developmental outcome. OBJECTIVES: Explore the relationship between blood pressure in the first 72 hours of life, perinatal factors, morbidity, and mortality in ELBW infants. Compare neuro-sensory outcome in ELBW infants with and without symptomatic hypotension. METHODS: We reviewed the outcome for all 156 infants with a birth weight <1000 g admitted to the neonatal intensive care unit covering the time period 1998 to 1999. Infants who received fluid pushes and/or pressors during the first 72 hours of life in an attempt to increase blood pressure were regarded as "symptomatic" or "treated infants"; the others were designated "non-treated infants." Follow-up at 20 months corrected age included neurologic status, Bayley motor/mental evaluation, plus tests of vision and hearing. Statistical analysis was by SPSS 11.0. Univariate and multivariate analyses were conducted to determine morbidities associated with symptomatic hypotension. RESULTS: A total of 59 infants (mean BW 714 +/- 154 g; GA 24.9 +/- 1.7 weeks) required BP support; 97 infants (mean BW 768 +/- 141 g; GA 26.1 +/- 1.9 weeks) received no BP support. The groups had similar race, gender, delivery mode, and maternal socioeconomic status. Thirty-five (22%) infants died, including 20 who received BP support. There were more infants with severe IVH (grade III/IV), 19% versus 2%, and the mortality was greater, 34% versus 16%, in those infants who received BP support. Of the 121 survivors, 110 (91%) had complete follow-up evaluations. Multivariate analysis controlling for SES and neonatal morbidity revealed that symptomatic hypotension is associated with delayed motor development (-6.0; SE 3.1) and hearing loss (O.R. 8.9; CI 0.92-86.3). CONCLUSIONS: Symptomatic hypotension in ELBW infants in the first 72 hours of life is associated with significant short-term and long-term morbidity. Infants with symptomatic hypotension are more likely to have delayed motor development, hearing loss, and death.

Blood pressure disorders in the neonate: hypotension and hypertension.

Although many sick newborns are treated for hypotension and hypertension, the normal physiologic blood pressure range ensuring appropriate organ perfusion is uncertain. Treatment decisions are based on statistically defined gestational and postnatal age-dependent normative blood-pressure values, combined with clinical intuition, because of difficulties evaluating organ perfusion and adequacy of cerebral oxygen delivery. Early-onset hypotension usually results from the combined effects of abnormal peripheral vasoregulation, myocardial dysfunction, and hypovolemia. Volume administration is the primary initial therapy but its use can be associated with significant untoward effects, especially in preterm infants, and should be limited to 10-20 mL/kg of isotonic saline. If the blood pressure cannot be normalized, dopamine should be added, and sometimes followed by adrenaline (epinephrine) and corticosteroids. Hypertension, most often caused by congenital or acquired renovascular disease or volume overload, needs a thorough search for the etiology and cautious treatment, so that blood pressure does not fall too quickly or too low.

Very low birth weight preterm infants with early onset neonatal sepsis: the predominance of gram-negative infections continues in the National Institute of Child Health and Human Development Neonatal Research Network, 2002-2003.

BACKGROUND: Early onset neonatal sepsis (EOS, occurring in the first 72 hours of life) remains an important cause of illness and death among very low birth weight (VLBW) preterm infants. We previously reported a change in the distribution of pathogens associated with EOS from predominantly gram-positive to primarily gram-negative organisms. OBJECTIVE: To compare rates of EOS and pathogens associated with infection among VLBW infants born at centers of the National Institute of Child Health and Human Development (NICHD) Neonatal Research Network during 3 time periods: 1991-1993; 1998-2000; and 2002-2003. STUDY DESIGN: Prospectively collected data from the NICHD Neonatal Research Network VLBW registry were retrospectively reviewed. Rates of blood culture confirmed EOS, selected maternal and infant variables and pathogens associated with infection were compared between 2002-2003 and 2 previously published cohorts. RESULTS: During the past 13 years, overall rates of EOS have remained stable (15-19 per 1000 live births of infants 401-1500 g). More than one-half of early infections in the 2002-2003 cohort were caused by gram-negative organisms (53%), with Escherichia coli the most common organism (41%). Rates of group B streptococcal infections remain low (1.8 per 1000 live births). Between 1991-1993 and 1998-2000, there was a significant increase in rates of E. coli infections; but in 2002-2003, there was no significant change (7.0 per 1000 live births). Infants with EOS continue to be at significantly increased risk for death compared with uninfected infants. CONCLUSION: EOS remains an uncommon but important cause of morbidity and mortality among VLBW infants. Gram-negative organisms continue to be the predominant pathogens associated with EOS.

Prolonged hospital stay for extremely premature infants: risk factors, center differences, and the impact of mortality on selecting a best-performing center.

OBJECTIVE: The first objective was to identify factors associated with prolonged hospital stay (PHS: hospitalized >42 weeks postmenstrual age) in extremely premature (EP: born less than or equal to 28 weeks gestation) infants. The second objective was to identify a PHS best-performing benchmark center. METHODS: This study was a retrospective cohort analysis of infants born < or =28 weeks gestation and admitted to one of 12 tertiary centers between January 1998 and October 2001. Risk-adjusted odds of PHS, defined as hospitalization beyond 42 weeks postmenstrual age, and the competing outcome, mortality, were assessed using logistic regression models. RESULTS: Among 3892 EP survivors who had complete data for multivariable analysis, 685 (18%) had PHS. Variables contributing to PHS included chronic lung disease (oxygen use at discharge home or 36 week postmenstrual age) (OR 6.75; 95% CI: 5.04 to 9.03), necrotizing enterocolitis requiring surgery (OR 13.83; 95% CI: 8.05 to 23.76), and >two episodes of late-onset sepsis (OR 2.39; 95% CI: 1.66 to 3.44). Centers' risk-adjusted PHS odds differed from the reference center, which had the lowest incidence of PHS and mortality (overall P-value <0.0001). Mortality contributed to PHS, but in an opposite direction compared to other factors. Centers with lowest PHS odds were among those with highest mortality. CONCLUSIONS: These findings suggest that reduction of CLD, surgical NEC, and late onset sepsis could reduce PHS in EP infants. Risk adjusted odds of PHS and mortality are both crucial for selecting a PHS best-performing center.

Effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants.

BACKGROUND: Glutamine is one of the most abundant amino acids in both plasma and human milk and may be conditionally essential in premature infants. However, glutamine is not provided by standard intravenous amino acid solutions. OBJECTIVE: We assessed the effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants receiving parenteral nutrition (PN). DESIGN: A total of 141 infants with birth weights of 401-1000 g were randomly assigned to receive a standard intravenous amino acid solution that did not contain glutamine or an isonitrogenous amino acid solution with 20% of the total amino acids as glutamine. Blood samples were obtained just before initiation of study PN and again after the infants had received study PN (mean intake: 2.3 +/- 1.0 g amino acids x kg(-1) x d(-1)) for approximately 10 d. RESULTS: Infants randomly assigned to receive glutamine had mean plasma glutamine concentrations that increased significantly and were approximately 30% higher than those in the control group in response to PN (425 +/- 182 and 332 +/- 148 micromol/L for the glutamine and control groups, respectively). There was no significant difference between the 2 groups in the relative change in plasma glutamate concentration between the baseline and PN samples. In both groups, there were significant decreases in plasma phenylalanine and tyrosine between the baseline and PN samples; the decrease in tyrosine was greater in the group that received glutamine. CONCLUSIONS: In extremely low-birth-weight infants, parenteral glutamine supplementation can increase plasma glutamine concentrations without apparent biochemical risk. Currently available amino acid solutions are likely to be suboptimal in their supply of phenylalanine, tyrosine, or both for these infants.

The NICHD neonatal research network: changes in practice and outcomes during the first 15 years.

The National Institute of Child Health and Human Development (NICHD) Neonatal Research Network was founded in 1986 to perform trials that, because of their size and complexity, were beyond the scope of a single center and required the expertise and resources of many collaborating centers. This report briefly documents changes in mortality, selected morbidities, and therapies amongst Network centers. The Network registry incorporating perinatal and neonatal data on all infants with a birth weight 501-1500 g cared for at participating centers served as the database. Mortality and selected morbidities were compared for 3 time periods, 1987/1988, (7 centers 1,765 infants, presurfactant); 1993/1994 (12 centers, 4,593 infants, postsurfactant and moderate antenatal corticosteroid utilization); and 1999/2000 (15 centers, 5,848 infants, postsurfactant and widespread corticosteroid use). Detailed outcomes for infants with birth weights between 501 and 800 g, and gestational ages of 23 to 25 weeks are also presented because they dramatically document the changes over time. Mortality for the entire cohort decreased from 23% in 1987/1988 to 17% in 1993/1994 and 14% in 1999/2000. Between 1987/1988 and 1999/2000 mortality prior to discharge, decreased from 66% to 45% for infants weighing 501-750 g; from 34% to 12% for birth weight between 751 to 1000 g, and from 13% to 7% for infants between 1001 and 1500 g. Mortality was higher in boys. Survival free of major morbidity (chronic lung disease/bronchopulmonary dysplasia, necrotizing enterocolitis or grade III/IV intraventricular hemorrhage) did not change significantly over time. Since the inception of the Network, multiple births have increased from 18% to 26%; deliveries by Cesarean section from 47% to 57%, and antenatal corticosteroid use increased from 16% to 79%. Surfactant, which was not used prior to 1990, is now given to 57% of the infants, including 87% with birth weights between 501 and 750 g. There have been significant decreases in the incidence of grade III-IV intraventricular hemorrhage from 18% in 1987/1988 to about 11% since 1993/1994, and periventricular leukomalacia from 8% to 3%. However, other morbidities, including necrotizing enterocolitis, patent ductus arteriosus, and late onset sepsis, have not changed substantially. Advances in perinatal care within NICHD Network centers have resulted in marked improvements in survival. Further advances are required to increase survival free of neonatal morbidity or neurodevelopmental impairment.