极低出生体重儿及极早早产儿1年随访

目的评估极低出生体重儿和极早早产儿随访到1岁时的体格发育状况、呼吸道感染频率及就诊频率等情况。方法将2008年5月至2009年5月四川大学华西第二医院新生儿科收治并存活出院的孕周小于32周或产重小于1500g的72例新生活产婴儿分为3组：第一组26例,孕周〈32周而产重≥1500g;第二组18例,孕周≥32周而产重〈1500g;第三组28例,孕周〈32周且产重〈1500g。于校正胎龄1岁时收集生长状况、呼吸道感染频率及就诊次数等信息。结果出院后随访到1岁时,第三组体重、头围的落后率高于第一组,身长的落后率高于第一组和第二组;第三组的中位呼吸道感染频率（15.5）较第一组（12.5）和第二组（8.5）高,第三组中位就诊次数（27.5）比第一组（17.5）和第二组（15.5）高。结论本研究结果提示,校正胎龄1岁时同是极低出生体重儿和极小胎龄早产儿的随访情况较仅为极低出生体重或极小胎龄的患儿要差,因此,胎龄和产重在评估早产儿预后方面同样重要。     

Neonatal procedural pain exposure predicts lower cortisol and behavioral reactivity in preterm infants in the NICU

Data from animal models indicate that neonatal stress or pain can permanently alter subsequent behavioral and/or physiological reactivity to stressors. However, cumulative effects of pain related to acute procedures in the neonatal intensive care unit (NICU) on later stress and/or pain reactivity has received limited attention. The objective of this study is to examine relationships between prior neonatal pain exposure (number of skin breaking procedures), and subsequent stress and pain reactivity in preterm infants in the NICU. Eighty-seven preterm infants were studied at 32 (+/-1 week) postconceptional age (PCA). Infants who received analgesia or sedation in the 72 h prior to each study, or any postnatal dexamethasone, were excluded. Outcomes were infant responses to two different stressors studied on separate days in a repeated measures randomized crossover design: (1) plasma cortisol to stress of a fixed series of nursing procedures; (2) behavioral (Neonatal Facial Coding System; NFCS) and cardiac reactivity to pain of blood collection. Among infants born 相似文献   

Improved birth weight table for neonates developed from gestations dated by early ultrasonography

Most previously published tables of birth weight percentiles as a function of gestational age have been derived from neonates with imprecise gestational dating. In order to improve the accuracy of neonatal birth weight percentiles, we developed a birth weight table based on measurements from a group of neonates who had accurate gestational dating by prenatal first trimester ultrasonography. By matching a database of obstetrical ultrasonograms over a 5 year period to birth records at our institution, 3718 newborn infants with gestational dating by first trimester ultrasonography were identified. Statistical smoothing and regression techniques were applied to gestational age at birth and birth weight data to develop a table for the 10th, 50th, 90th, and other weight percentiles for 25 weeks of gestation onward. The weight table developed from our population has lower 50th and 90th percentile weights, and narrower 10th to 90th percentile ranges, at 25 to 35 weeks than in prior tables. At 39 to 43 weeks, our 10th, 50th, and 90th percentile weights are higher than those in previous tables. Our weight table for newborn infants, based on measurements from neonates with accurate dating, permits improved assignment of weight percentiles for gestational age and more accurate diagnosis of growth disorders in fetuses and neonates.     

Neuromotor behavioural assessment of preterm infants at risk for impaired development

This study was undertaken to evaluate the effectiveness of a new neuromotor behavioural assessment in identifying preterm infants whose development was potentially at risk as a result of their early birth and immediate postnatal experiences. All infants born at less than 30 weeks gestation or who weighed less than 1000g at birth and cared for in the Mater Hospital's Neonatal Intensive Care Unit in Brisbane over a two year period were included in the study. Infants were assessed in their third week of life and again at 36 weeks gestational equivalent age, or prior to discharge, whichever occurred sooner. Results indicate that the assessment is effective in differentiating those infants who suffered from adverse neonatal events from those who did not, when assessed between 30 and 36 weeks gestational equivalent age. The assessment did not prove useful for infants of less than 30 or greater than 36 weeks gestational equivalent age.     

Renal failure, comorbidity and mortality in preterm infants

OBJECTIVE: To evaluate patient characteristics and risk factors for mortality in critically ill preterm infants with renal failure, with a special focus on infants with extremely low birth weight. DESIGN: Retrospective cohort study with five year follow-up of all premature infants who were treated in the neonatal intensive care unit in 2002 and developed postnatal serum creatinine > or =1.5 mg/dl and/or urine output <1 ml/kg per h. SETTING: Tertiary Care University Hospital of the Medical University of Vienna PATIENTS: Sixteen of 359 premature infants (9 boys, 7 girls) fulfilled the inclusion criteria for renal failure. Their median gestational age was 30 weeks (range 24-36) with a median birth weight of 811.5 g (range 588-2662). MEASUREMENTS AND MAIN RESULTS: The most common causes of renal failure were sepsis and ischemic events. All infants were managed conservatively with corrections of fluids, electrolytes and acidosis, including medication with diuretics and dopamine. Eleven infants with renal failure (69%) died in multiorgan failure. Infants with low urine output, higher scores for failed organs or low birth weight were significantly more likely to die. Infants with very low birth weights had higher scores for failed organs (all P < 0.05). CONCLUSION: Oliguria/anuria, multiorgan failure and immaturity were significant risk factors for mortality in preterm infants with renal failure. Further studies and/or more registry data are needed to determine whether these infants died with or from renal failure, and whether dialysis would improve outcome in this special population.     

Behavioral responses to pain are heightened after clustered care in preterm infants born between 30 and 32 weeks gestational age

OBJECTIVE: To compare biobehavioral pain responses of preterm infants born at differing gestational ages (GAs) when pain was preceded by a rest period or by a series of routine nursing interventions. METHODS: In a randomized, within subjects, cross-over design, facial (Neonatal Facial Coding System), sleep/wake state and heart rate (HR) responses of 43 preterm infants [mean birth weight: 1303 g (range 590 g to 2345 g); mean GA at birth: 30 weeks (range 25 to 32)] were examined across 3 phases of blood collection (Baseline, Lance, and Recovery) under 2 conditions: pain after a 30-minute rest period versus pain after a series of routine nursing interventions (clustered care). Infant behavioral responses were coded from continuous bedside videotapes. HR was analyzed using custom physiologic signal processing software. RESULTS: Infants born at earlier GA (<30 wk) had equally intense facial responses during the Lance phase regardless of condition. However, later born infants (> or =30 wk GA) showed heightened facial responses indicative of sensitized responses during blood collection when it was preceded by clustered care (P=0.05). Moreover, later born infants had significantly lower facial (P=0.05) and HR (P=0.04) reactivity during Recovery when blood collection followed clustered care. DISCUSSION: Earlier born preterm infants showed heightened states of arousal and poor ability to modulate HR during Recovery when an invasive procedure was preceded by routine tactile nursing procedures. Alternatively, later born infants exhibited sensitized responses when clustered care preceded blood collection. Our findings support the importance of cue based individualized approaches to care.     

Pain Sensitivity and Thermal Detection Thresholds in Young Adults Born Preterm With Very Low Birth Weight or Small for Gestational Age at Term Compared With Controls

The objective of this prospective long-term follow-up study was to investigate whether somatosensory function is altered among young adults born preterm with very low birth weight (VLBW; ≤1,500 g) or small for gestational age (SGA; <10th percentile) at term. In a blinded quantitative sensory testing protocol, we determined thermal detection, thermal pain, and pressure pain thresholds and the response to prolonged supra-threshold heat among 51 VLBW, 66 term SGA, and 86 term-born controls (birth weight ≥10th percentile) at 28 years. Self-reported chronic pain was also investigated. Except for increased sensitivity to cool in the term SGA group versus controls, we found no significant group differences regarding thermal or pain thresholds. Overall, male participants had higher pain thresholds, and no significant interactions of group and sex were observed (P > .14). Within the VLBW group, neonatal mechanical ventilation was associated with reduced sensitivity to cool, and length of mechanical ventilation correlated with lower pressure pain thresholds. The response to prolonged supra-threshold heat was similar between the groups, and the prevalence of self-reported chronic pain was not reliably different. In conclusion, low birth weight young adults were as sensitive to thermal and pain stimuli as term-born, normal birth weight controls, with the same sex differences.

Extrauterine growth restriction: a continuing problem in the NICU

Extrauterine growth restriction (EGR) is an identifiable marker of severe nutritional deficit during the first weeks of life. Infants with EGR have growth values at or below the 10th percentile of intrauterine growth expectation based on estimated gestational age. Although all preterm sick infants are at risk for EGR, risk is greatest for those infants <1500 g at birth. As estimated gestational age and birthweight decrease, the incidence of extrauterine growth restriction increases. The duration of initial weight loss also increases as birthweight decreases, compounding the difficulty of attaining appropriate growth. To decrease the incidence and consequences of nutritional deficit, NICU caregivers should learn more about EGR, implement assessment protocols to identify EGR, seek opportunities to decrease energy needs of at-risk infants, and work toward enhancing nutritional status of VLBW infants through innovative nutritional management.     

超声评价新生儿胼胝体发育及影响因素

目的通过颅脑超声监测胼胝体的生长率,分析新生儿胼胝体发育的影响因素,为早期评价和治疗脑发育性疾病提供依据。 方法选择2016年4月至12月就诊于兰州大学第二医院新生儿重症监护室（NICU）的97例新生儿,其中,早产儿54例（27~34周）,足月儿43例。所有新生儿于出生后0~6周每周行颅脑超声检查并测量胼胝体矢状长度,通过独立样本t检验比较早产儿、足月儿出生后0~6周胼胝体生长率。采用Spearman相关分析孕周、新生儿出生体质量与胼胝体生长率之间的关系。 结果（1）新生儿出生时胼胝体矢状长度与孕周、出生体质量成正相关（r=0.57、0.58）;（2）早产儿出生后0周、2周、3周、4周、5周、6周胼胝体长度均低于足月儿,差异均有统计学意义（t=6.22、6.51、7.81、8.87、10.25、11.64,P均<0.001）;（3）早产儿、足月儿出生后0~2周胼胝体生长率比较,差异无统计学意义（P>0.05）,出生后2~6周每周早产儿胼胝体生长率均低于足月儿,差异均有统计学意义（t=13.91、14.76、13.85、12.21,P均<0.001）。 结论新生儿胼胝体的发育与孕周、出生体质量有关;颅脑超声能实时动态监测胼胝体的生长发育。     

Neonatal color Doppler US study: normal values of cerebral blood flow velocities in preterm infants in the first month of life

The aim of this study is to generate normal reference values of cerebral blood flow velocities (CBFV) and Doppler indices (DI) in the anterior (ACA) and the middle (MCA) cerebral arteries during the first month of life in "healthy" preterm infants. CBFV were obtained with color Doppler technique in seventy selected preterm infants divided in four groups of gestational age (GA) (25 to 28; 29 to 30; 31 to 32; 33 to 35 wk). Our data demonstrate that CBFV increase with rising GA, birth weight (BW) and postnatal age. Additionally, we can provide the median values, tenth and ninetieth percentiles of CBFV and DI, in the ACA and MCA in each GA group as reference normal values of CBFV and DI in preterm newborn.     

血清表皮生长因子与早产儿肺发育相关研究

目的 探讨血清表皮生长因子水平与早产儿肺发育的相关性.方法 选择住院早产儿35例.根据胎龄分成3组,分别是①28周≤胎龄〈32周,9例,②32周≤胎龄〈35周,14例,③35周≤胎龄〈37周,12例,同时根据有无并发早产儿肺透明膜病（HMD）分为HMD组19例,非HMD组16例;对照组选择足月儿高胆红素血症住院患儿12例.无其他并发症.采用酶联免疫吸附测定法（ELISA）,35例早产儿和12例对照组足月儿分别于出生1h、24h、72h、和生后第7天空腹股静脉采血测定血清表皮生长因子水平.结果 早产儿组出生1h、24h、72h、和生后第7天.血清表皮生长因子含量水平均呈递增关系,差异有显著性;早产儿组与足月儿组血清表皮生长因子含量水平于出生1h、24h、72h差异有显著性,生后第7天差异无显著性;在生后1h、24h、72h,早产儿有HMD组与无HMD组患儿血清表皮生长因子含量水平差异有显著性.结论 早产儿出生后血清表皮生长因子含量水平呈递增关系,提示早产儿出生后体内EGF合成和释放增加,可能促进肺脏器成熟;早产儿组与足月儿组血清表皮生长因子含量水平出生后差异有显著性,早产儿出生后血清EGF浓度水平和HMD的严重程度正相关,提示在新生儿早期检测血清表皮生长因子含量可以作为HMD发病的预测指标.     

Impact of Prematurity on Perinatal Mortality and Morbidity

Severe prematurity is a prime factor causing perinatal mortality or morbidity. In Finland 1 % of babies are born before 32 completed weeks of pregnancy and 0.9 % are delivered with a birth weight of 1500 g or less. Since transport of a baby in utero is preferable to transporting a neonate, approximately 85 % of infants below 1000 g and 90 % of infants between 1000 to 1499 g are delivered in departments with facilities for neonatal intensive care. The rate of caesarean delivery is approximately 50 % in pregnancies between 26 and 28 weeks, while the overall caesarean section rate is 15 %. Deaths of low birth weight babies account for 66 % of the total perinatal mortality and those of very low birth weight babies 46 %. Intrauterine deaths constitute two thirds and neonatal deaths one third of perinatal mortality among very low birth weight babies. In Turku, neonatal survival rate for infants of 500 to 749 g was 61.5 % and for infants of 750 to 999 g, 77.3 %. In Turku respiratory distress syndrome is one of main complications of prematurity that has led to death in 11.2 % of infants in recent years. Of the survivors, 85 % have been healthy at the age of two years. The incidence of the bronchopulmonary dysplasia among very low birth weight infants has been 19.7 %. In recent years, the incidence of severe brain haemorrhage has been 32 % among infants with a birth weight below 1000 g.     

Impact of prematurity on perinatal mortality and morbidity.

Severe prematurity is a prime factor causing perinatal mortality or morbidity. In Finland 1% of babies are born before 32 completed weeks of pregnancy and 0.9% are delivered with a birth weight of 1500 g or less. Since transport of a baby in utero is preferable to transporting a neonate, approximately 85% of infants below 1000 g and 90% of infants between 1000 to 1499 g are delivered in departments with facilities for neonatal intensive care. The rate of caesarean delivery is approximately 50% in pregnancies between 26 and 28 weeks, while the overall caesarean section rate is 15%. Deaths of low birth weight babies account for 66% of the total perinatal mortality and those of very low birth weight babies 46%. Intrauterine deaths constitute two thirds and neonatal deaths one third of perinatal mortality among very low birth weight babies. In Turku, neonatal survival rate for infants of 500 to 749 g was 61.5% and for infants of 750 to 999 g, 77.3%. In Turku respiratory distress syndrome is one of main complications of prematurity that has led to death in 11.2% of infants in recent years. Of the survivors, 85% have been healthy at the age of two years. The incidence of the bronchopulmonary dysplasia among very low birth weight infants has been 19.7%. In recent years, the incidence of severe brain haemorrhage has been 32% among infants with a birth weight below 1000 g.     

PRIME (preterm infants need milk early) - Success of a multidisciplinary quality improvement project in a tertiary neonatal unit

BackgroundMaternal milk (MM) protects against necrotising enterocolitis and other morbidities in preterm infants. Guidelines advise the early initiation of enteral feeds after birth using MM.ObjectivePReterm Infants need Milk Early (PRIME) is a multidisciplinary initiative introduced to improve the early provision of MM among preterm infants.MethodsSetting and inclusion criteria: Inborn infants, born <32 weeks gestational age (GA) or with a birth weight (BW) < 1500g, who received MM for the first time in our tertiary neonatal unit.DesignQuality Improvement Project (QIP) following Plan Do Study Act cycle methodology. We conducted a cross-sectional survey amongst staff (n = 100) to evaluate knowledge and attitudes towards MM for preterm infants at baseline. The survey findings informed the initiative which included development of guidelines and a multidisciplinary staff teaching programme. A pre-intervention cohort provided baseline data for comparison. Study outcomes were clinical and knowledge based pre- and post-intervention.ResultsThe pre-intervention cohort included 121 infants born in 2016, GA 30 (27, 31) weeks, BW 1230 (915, 1440) g. The post-intervention cohort included 197 infants born May 2018–December 2019, GA 29 (27, 31) weeks, BW 1180 (855, 1490) g. Pre-intervention, the time to 1st MM was 35 (18, 55) hours and 34% (n = 41) received MM within 24 h of birth. Post-intervention, the time to 1st MM was 19 (10, 37) hours and 60% (n = 119) received MM within 24 h. The follow-up survey amongst staff (n = 91) found improvements in knowledge and attitudes.ConclusionWe improved the time to first MM and staff knowledge and attitudes following the introduction of our QIP.     

早期综合干预对早产低体质量儿生后早期生长的影响

目的探讨实施早期综合干预对早产低出生体质量儿出生后早期生长的影响。方法将60例早产低出生体质量儿按不同的出生时间分为2组,每组30例。2009年1-12月出生的早产低出生体质量儿为对照组,只接受婴幼儿系统管理,进行常规育儿;2010年1-12月出生的早产低出生体质量儿为观察组,采取认知、语言、情感、抚触、被动体操、主动运动训练和营养支持等早期综合干预。干预3个月后,对2组早产低出生体质量儿喂奶的科学合理性、患病率,新生儿出生后3个月时的身长、体质量、头围的追赶生长情况进行比较。结果观察组喂奶的科学合理性所占比例明显优于对照组,新生儿患病率明显低于对照组（均P〈O．05）。观察组新生儿在出生后3个月时的身长、体质量、头围的追赶生长所占比例均明显高于对照组（均P〈O．05）。结论对早产低出生体质量儿实施早期综合干预可促进早产儿的胃肠功能发育,促进早产后的早期生长。     

Adverse birth outcomes in relation to prenatal sonographic measurements of fetal size.

OBJECTIVE: To evaluate and quantify the prediction of multiple neonatal outcomes by sonographically estimated fetal weight across a broad range of gestational ages. METHODS: A retrospective cohortanalysis was conducted among women with certain gestational age (n = 1,376) seen at the University of California San Francisco from 1994 through 1997. The relative risks for small size at birth, small (low birth weight) for gestational age, and adverse neonatal outcomes were compared between small and average-sized fetuses. RESULTS: Fetuses with an estimated fetal weight in the 5th percentile or less for gestational age were at increased risk of a birth weight less than 2,000 g (relative risk, 6.5), a birth weight in less than the 3rd percentile for gestational age (relative risk, 10.1), preterm birth (relative risk, 2.2), extreme preterm birth (relative risk, 5.7), prolonged neonatal hospital stay (relative risk, 2.7), neonatal intensive care unit admission (relative risk, 3.2), and stillbirth or neonatal death (relative risk, 7.7) compared with average-sized fetuses (all P < .0001). With intrauterine growth restriction defined as an estimated fetal weight in the 5th percentile or less for gestational age, up to 29% of fetuses with adverse neonatal outcomes were detected, for false-positive rates of only 4% to 5%. After adjusting for confounding variables, low estimated fetal weight remained a significant predictor of neonatal morbidity and mortality. CONCLUSIONS: Morbidity and mortality are significantly increased among fetuses with an estimated fetal weight in the 5th percentile or less for gestational age.     

Population-based birth weight reference percentiles for Chinese twins

Background: Birth weight percentiles by gestational age are important for assessing prenatal growth and predicting postnatal outcomes of newborns. Several countries have developed nation-specific birth weight references for twins, but China still lacks such references.

Methods and results: Birth weight data for twins born between October 2006 and September 2015 were abstracted from the China National Population-based Birth Defects Surveillance System. A total of 54,786 live twin births aged?≥28 weeks of gestation without birth defects were included in the analysis. The LMS method was adopted to generate gestational age-specific birth weight percentiles and curves for male and female twins separately. Significant differences were observed between the current reference and other references developed for Chinese or non-Chinese twins. The neonatal mortality rate in this cohort was 12.3‰, and much higher rates at very early gestation weeks were identified in small-for-gestational-age twins grouped by the newly developed reference cutoffs.

Conclusions: The established birth weight centiles represent the first birth weight norm for contemporary Chinese twins and can be a useful tool to assess growth of twins in clinical and research settings.

• Key Messages

• There have been no population-based birth weight percentiles for Chinese twins prior to this study. The established birth weight centiles for female and male twins are markedly lower than those for Chinese singletons. Twin-specific curves should be used for determining inappropriate for gestational age in twins rather than using existing singleton reference.

• The birth weight percentiles for twins differed significantly from those for non-Chinese twins. In addition to ethnic influences, the observed differences could be ascribed to variations in prenatal care, fetal or maternal nutrition status or other environmental factors.

• Neonatal mortality rates varied considerably among twins grouped by the newly developed reference percentiles. Small-for-gestational-age twins had much higher mortality than did appropriate-for-gestational-age twins, highlighting the need to reduce postnatal mortality by improving perinatal health care for twins.

     

双胎体重差异与新生儿疾病

目的：探讨双胎出生体重差异大小与新生儿疾病关系。方法回顾性分析我院分娩的双胎61对，将分娩后两新生儿按体重差异分组，比较不同体重差异对新生儿疾病发生率的影响及高危因素。结果不同体重差异在新生儿贫血（χ2＝35.43）、高胆红素血症（χ2＝31.22）、新生儿低蛋白血症（χ2＝49.34）、新生儿败血症（χ2＝21.56）、新生儿颅内出血（χ2＝28.78）、新生儿肺炎（χ2＝33.38）、新生儿呼吸暂停（χ2＝54.34）、新生儿窒息（χ2＝16.28）、新生儿喂养不耐受（χ2＝25.34）、新生儿宫外营养不良（χ2＝36.32）的发生率之间均有显著性差异（P＜0.01）；而新生儿红细胞增多症（χ2＝3.89）和新生儿畸形（χ2＝10.21）的发生率均无显著性差异（P＞0.05）。母亲高龄（χ2＝12.34）、早产儿（χ2＝23.56）、单卵双胎（χ2＝18.80）、妊娠期糖尿病（χ2＝17.38）和妊娠期高血压（χ2＝22.21）均为双胎体重差异增加高危因素（P＜0.01）。结论双胎体重差异对新生儿期相关疾病的发病率具有一定影响，高龄、早产儿、单卵双胎、体外受精-胚胎移植（IVF-ET）、妊娠期糖尿病和妊娠期高血压均为体重差异高危因素。     

Postnatal longitudinal reference growth of very preterm infants on exclusive human milk feeding till discharge

Background and objectivesGrowth measurements help to confirm an infant's healthy development and also help to identify early, potential health or nutritional problems. Appropriate Growth is also a criteria for early discharge of very preterm infants from NICU. To identify the infants who have growth faltering, we need to monitor the anthropometry regularly and compare with a local standard. Currently there is no best strategy of monitoring growth in VLBW infants. Objective of this study is to assess postnatal longitudinal growth for very preterm infants on Exclusive human milk feeding till discharge.Materials and methodsAll newborns with gestation <33 weeks at birth and admitted to the NICU included in this study. Those with major malformations, death before discharge and babies transferred to another hospital for care before 7 days were excluded. Nutritional and fluid management of all enrolled infants was guided by a nutritional protocol elaborating on both parenteral nutrition and enteral nutrition. All enrolled infants were on exclusive human milk (mothers own milk or donor human milk) till hospital discharge. All the discharged enrolled infants were followed up in the high risk follow up clinic weekly till the infant reached a post-menstrual gestational age of 37–40 weeks. Post-natal growth charts for each gestational age group was created using polynomial regression and linear regression.ResultsDuring the study period a total of 398 eligible infants were admitted to the neonatal units. After excluding 76 infants (36 died in hospital, 40 infants got shifted to another hospital before complete care), 322 infants were eligible for growth assessment. The average time to reach full feeds was 7.7 ± 5.2 days and time to regain birth weight was 12.2 ± 4.8 days. The average weight gain from time to regain birth weight till hospital discharge and till last PMA was 17.6 ± 16 gm/kg/day and 19.8 ± 8 gm/kg/day respectively. The rate of growth for length and head circumference in hospital and till last PMA was 0.8 ± 1 cm/week, 0.7 ± 0.4 cm/week and 0.38 ± 0.8 cm/week, 0.55 ± 0.7 cm/week respectively. The rate of growth in weight, length and head circumference differed significantly among the gestational age groups as shown in Charts.ConclusionInfants with exclusive fortified human milk feeding had growth rate very similar to in-utero growth from time to regain birth weight till hospital discharge or till last PMA at follow up.     

The cost of prematurity: hospital charges at birth and frequency of rehospitalizations and acute care visits over the first year of life: a comparison by gestational age and birth weight

The proportion of preterm and low-birth-weight infants has been growing steadily for two decades. Most of the more than US 10 billion dollars spent on neonatal care in the United States in 2003 was spent on the 12.3% of infants who were born preterm. Research has shown higher initial hospital costs and a higher rate of acute care visits and rehospitalization for preterm and low-birth-weight infants, but only a limited number of studies of the cost of prematurity that follow infants through the first year of life have been conducted. This study is a secondary analysis of data on a subset of infants drawn from a randomized clinical trial that examined health outcomes and health care costs in women with high-risk pregnancies and their infants. For the current study, a sample of 84 singleton infants was chosen. Forty-three infants (51%) were full term (37 weeks' gestation or more) and 41 (49%) were born preterm (less than 37 weeks' gestation). Fifty-five infants (65.5%) were born at normal birth weights (2,500 g or greater), 24 (28.5%) were born at low birth weights (1,501 to 2,499 g), and five (6%) were born at very low birth weights (less than 1,500 g). Data on the initial hospital charges and the rates of rehospitalization and acute care visits in the first year of life in relation to gestational age and birth weight were collected. The results clearly demonstrated that the charges for initial hospitalizations increased as birth weights and gestational ages decreased. Low-birth-weight infants were less likely to have unscheduled acute care visits than normal-birth-weight infants. Interventions to improve prenatal care targeted to women at high risk for delivering preterm or low-birth-weight infants would reduce health care costs and improve health outcomes of infants as well.