"Late-preterm" infants: a population at risk

Late preterm birth and risk of developing asthma

OBJECTIVE

To evaluate the association between gestational age at birth (late preterm vs term) and risk for physician-diagnosed asthma.

STUDY DESIGN

We conducted a retrospective cohort study using the Third National Health and Nutrition Examination Survey (1988-1994) linked natality files. The study included children age 2-83 months from singleton births, born late preterm (n=537) or term (n=5650). Using survival analysis, we modeled time to diagnosis of asthma; children with no asthma diagnosis were censored at the age of their survey interview. We used Cox proportional hazard regression to estimate hazard ratios and 95% confidence intervals for gestational age and asthma risk, adjusting for maternal age, maternal education, parental history of asthma/hay fever, maternal smoking history during pregnancy, race/ethnicity, and sex of the child.

RESULTS

Adjusted analysis showed that physician-diagnosed asthma was modestly associated with late preterm birth (hazard ratio, 1.3; 95% confidence interval, 0.8-2.0), but this association was not statistically significant (P=.30).

CONCLUSIONS

Our study found that late preterm birth was not associated with a diagnosis of asthma in early childhood.

Respiratory morbidity and lung function in preterm infants of 32 to 36 weeks' gestational age

Normal lung development follows a series of orchestrated events. Premature birth interrupts normal in utero lung development, which results in significant alterations in lung function and physiology. Increasingly, there are reports documenting the broad range of complications experienced by infants aged 34 to 36 weeks' gestational age (GA). Our objective was to summarize the evidence demonstrating respiratory system vulnerability in infants aged 34 to 36 weeks' GA and to review the developmental and physiologic principles that underlie this vulnerability. A comprehensive search for studies that reported epidemiologic data and respiratory morbidity was conducted on the PubMed, Medline, Ovid Biosis, and Embase databases from 2000 to 2009 by using medical subject headings "morbidity in late preterm infants," "preterm infants and lung development," "prematurity and morbidity," and "prematurity and lung development." Because the number of studies exclusive to infants aged 34 to 36 weeks' GA was limited, selected studies also included infants aged 32 to 36 weeks' GA. Of the 24 studies identified, 16 were retrospective population-based cohort studies; 8 studies were observational. These studies consistently revealed that infants born at 32 to 36 weeks' GA, including infants of 34 to 36 weeks' GA, experience substantial respiratory morbidity compared with term infants. Levels of morbidity were, at times, comparable to those observed in very preterm infants. The developmental and physiologic mechanisms that underlie the increased morbidity rate and alterations in respiratory function are discussed. We also present evidence to demonstrate that the immaturity of the respiratory system of infants 34 to 36 weeks' GA at birth results in increased morbidity in infancy and leads to deficits in lung function that may persist into adulthood.

Assessing jaundice in infants of 35-week gestation and greater

PURPOSE OF REVIEW

In 2004, the American Academy of Pediatrics officially recommended universal predischarge risk assessment for severe neonatal hyperbilirubinemia with the goal of minimizing subsequent risk of chronic bilirubin encephalopathy (formerly known as kernicterus). In this article, we review recent research regarding jaundice predischarge risk assessment, current expert recommendations for universal predischarge bilirubin screening, and concerns expressed in the literature regarding these recommendations.

RECENT FINDINGS

A group of experts have recently recommended universal predischarge bilirubin screening to identify newborns at risk for developing severe neonatal hyperbilirubinemia. In contrast, the United States Preventive Services Task Force states that there is insufficient evidence to make this recommendation. Transcutaneous bilirubinometry has emerged as a noninvasive, quick method to screen for neonatal hyperbilirubinemia, although refinement and validation of transcutaneous bilirubin nomograms are needed. Newer studies suggest that the combined use of a predischarge bilirubin and gestational age risk assessment offers a simple, objective, and accurate way to identify infants at risk for subsequent, severe hyperbilirubinemia.

SUMMARY

All newborns should be systematically assessed for risk of developing severe hyperbilirubinemia prior to hospital discharge. Although limited data exist to recommend its use universally, predischarge bilirubin screening should be considered given recent expert opinion. The role of transcutaneous bilirubinometry remains promising, although further research evaluating and validating its use in varied and diverse populations is imperative. Combined models of risk assessment may offer the best approach to identifying infants at risk for subsequent, severe hyperbilirubinemia.

Preterm birth after mature fetal lung indices: is there any neonatal morbidity?

OBJECTIVE

To determine the frequency of immediate morbidities in neonates with evidence of mature fetal lung indices who delivered before 37 weeks gestation.

METHODS

A retrospective analysis was performed on pregnancies resulting in birth at < 37 weeks after mature fetal lung was documented by phosphatidylglycerol, lecithin/sphingomyelin ratio, or TDx-FLM studies. Pregnancies with multifetal gestations, maternal diabetes, or fetal anomalies were excluded.

RESULTS

179 patients were included. Eighty-one (45.3%) neonates did not sustain any morbidity, and 98 (54.7%) neonates sustained one or more morbidities. Compared to neonate without any morbidity, neonates experiencing morbidities were delivered at significantly younger gestation (35.7 ± 1.1 vs. 34.9 ± 1.5 weeks, respectively, p < 0.001) had lower birth- weight (2632.2 ± 475.5 vs. 2395.3 ± 496 g, respectively, p < 0.001), and required longer hospital stay (3.7 ± 2.8 vs. 6.9 ± 7.5 days, p < 0.001). A multivariate regression model was performed to control for the effect of birth-weight, steroid administration, and preterm premature rupture of membrane. An earlier gestational age at delivery was associated with a higher risk of neonatal morbidity. The risk of neonatal morbidity decreased by 40% (OR = 0.60, 95% CI = 0.41-0.88; p = 0.009) for each 1 week increase in gestational age.

CONCLUSION

Even in the presence of documented fetal lung maturity, major morbidities--including respiratory distress - may still occur.

Induced preterm birth in sheep: a suitable model for studying the developmental effects of moderately preterm birth

Our aim was to characterize an ovine model of preterm birth that allows analysis of the developmental effects of preterm birth in the absence of postnatal confounding factors. Preterm birth was induced at 131 days of gestation in 82 lambs; controls (n = 31) were born at term (145 days). Overall survival of preterm lambs was 60%; males had significantly lower survival than females (44% vs 76%); 94% of term lambs survived. Although the birth weight of preterm lambs was approximately 0.9 kg lower than in term lambs, the crown-to-rump and forelimb lengths were similar. At 9 weeks after term-equivalent age, there were no differences in body weight or dimensions between preterm and term lambs; when adjusted for body weight, the heart was 21% heavier in preterm than term lambs. We conclude that moderately preterm birth in sheep is characterized by a greater survival of female lambs than males and has significant effects on organ development.

Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior to 37 weeks' gestation for improving pregnancy outcome

BACKGROUND

Delivery after preterm prelabour rupture of the membranes (PPROM) may be initiated soon after PPROM or, alternatively, be delayed. It is unclear which strategy is most beneficial for mothers and their babies.

OBJECTIVES

To assess the effect of planned early birth compared with expectant management for pregnancies complicated with PPROM prior to 37 weeks' gestation.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (May 2009), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 1), MEDLINE (1996 to May 2009), EMBASE (1974 to May 2009), and reference lists of trials and other review articles.

SELECTION CRITERIA

Randomised controlled trials comparing expectant management with early delivery for women with PPROM prior to 37 weeks' gestation. We excluded quasi randomised trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated trials for inclusion into the review and for methodological quality.

MAIN RESULTS

We included seven trials (690 women) in the review. We identified no difference in the primary outcomes of neonatal sepsis (risk ratio (RR) 1.33, 95% confidence interval (CI) 0.72 to 2.47) or respiratory distress (RR 0.98, 95% CI 0.74 to 1.29). Early delivery increased the incidence of caesarean section (RR 1.51, 95% CI 1.08 to 2.10). There was no difference in the overall perinatal mortality (RR 0.98, 95% CI 0.41 to 2.36), intrauterine deaths (RR 0.26, 95% CI 0.04 to 1.52) or neonatal deaths (RR 1.59, 95% CI 0.61 to 4.16) when comparing early delivery with expectant management. There was no significant difference in measures of neonatal morbidity, including cerebroventricular haemorrhage (RR 1.90 95% CI 0.52 to 6.92), necrotising enterocolitis (RR 0.58, 95% CI 0.08 to 4.08), or duration of neonatal hospitalisation (mean difference (MD) -0.33 days, 95% CI -1.06 to 0.40 days). In assessing maternal outcomes, we found that early delivery increased endometritis (RR 2.32, 95% CI 1.33 to 4.07), but that early delivery had no effect on chorioamnionitis (RR 0.44, 95% CI 0.17 to 1.14). There was a significant reduction of early delivery on the duration of maternal hospital stay (MD -1.13 days, 95% CI -1.75 to -0.51 days).

AUTHORS' CONCLUSIONS

There is insufficient evidence to guide clinical practice on the benefits and harms of immediate delivery compared with expectant management for women with PPROM. To date all of the clinical trials have had methodological weaknesses and have been underpowered to detect meaningful measures of infant and maternal morbidity.

Timing of elective repeat caesarean section: maternal and neonatal morbidity and mortality

Timing of elective repeat caesarean section should take into account both fetal and maternal considerations. The percentage of caesarean deliveries has dramatically increased during the last decades. It undoubtedly leads to an increase in the number of women having multiple caesarean sections. While maternal morbidity increases with increased number of caesarean sections, when compared with their term counterparts, late pre-term infants face increased morbidity. Establishing the optimal time of delivery for both mother and child is a major challenge faced by clinicians. The aim of this review is to better understand neonatal and maternal morbidity and mortality that are associated with elective repeat caesarean section, and to provide an educated decision regarding the optimal timing for elective repeat caesarean section.

Role of the pediatric nurse practitioner in promoting breastfeeding for late preterm infants in primary care settings

The preterm birth rate has been increasing steadily during the past two decades. Up to two thirds of this increase has been attributed to the increasing rate of late preterm births (34 to < 37 gestational weeks). The advantages of breastfeeding for premature infants appear to be even greater than for term infants; however, establishing breastfeeding in late-preterm infants is frequently more problematic. Because of their immaturity, late preterm infants may have less stamina; difficulty with latch, suck, and swallow; temperature instability; increased vulnerability to infection; hyperbilirubinemia, and more respiratory problems than the full-term infant. Late preterm infants usually are treated as full term and discharged within 48 hours of birth, so pediatric nurse practitioners in primary care settings play a critical role in promoting breastfeeding through early assessment and detection of breastfeeding difficulties and by providing anticipatory guidance related to breastfeeding and follow-up. The purpose of this article is to describe the developmental and physiologic immaturity of late preterm infants and to highlight the role of pediatric nurse practitioners in primary care settings in supporting and promoting breastfeeding for late preterm infants.

Comparative costs of hospitalisation among infants at high risk for respiratory syncytial virus lower respiratory tract infection during the first year of life

OBJECTIVE

This retrospective cohort study compared the total cost of hospitalisation due to respiratory syncytial virus (RSV) lower respiratory tract infection (LRI) during the first year of life between late-preterm (33-36 weeks gestational age [wGA]) and term (≥ 37 wGA) infants.

RESEARCH DESIGN AND METHODS

A large national claims database of commercially insured members was examined to identify hospital admissions associated with RSV between January 2003 and June 2007 among infants at high risk for RSV LRI, including late-preterm infants. Hospital use and costs were compared with those of a reference cohort of term infants with RSV.

RESULTS

The cost of hospitalisation for RSV among late-preterm infants with at least one hospital admission associated with RSV (n=173) was twice that of term infants (n=1,983; $20,269 vs. 9,635; p< 0.001). The mean length of stay was also higher (5.3 vs. 3.4 days; p< 0.001). Approximately 21.9% of hospitalisations for late-preterm infants included an intensive care unit admission compared with 9.6% among term infants (p< 0.001).

LIMITATIONS

Reliance on ICD-9 codes to identify potential cohort members may result in misclassification and underreporting the cohort size for conditions of interest.

CONCLUSIONS

Hospitalisation costs and length of stay due to RSV LRI were significantly greater among late-preterm infants compared with term infants and higher than general estimates previously reported in the broader paediatric population.

Trends in birth weight and gestational length among singleton term births in the United States: 1990-2005

OBJECTIVE

To estimate changes over time in birth weight for gestational age and in gestational length among term singleton neonates born from 1990 to 2005.

METHODS

We used data from the U.S. National Center for Health Statistics for 36,827,828 singleton neonates born at 37-41 weeks of gestation, 1990-2005. We examined trends in birth weight, birth weight for gestational age, large and small for gestational age, and gestational length in the overall population and in a low-risk subgroup defined by maternal age, race or ethnicity, education, marital status, smoking, gestational weight gain, delivery route, and obstetric care characteristics.

RESULTS

In 2005, compared with 1990, we observed decreases in birth weight (-52 g in the overall population, -79 g in a homogenous low-risk subgroup) and large for gestational age birth (-1.4% overall, -2.2% in the homogenous subgroup) that were steeper after 1999 and persisted in regression analyses adjusted for maternal and neonate characteristics, gestational length, cesarean delivery, and induction of labor. Decreases in mean gestational length (-0.34 weeks overall) were similar regardless of route of delivery or induction of labor.

CONCLUSION

Recent decreases in fetal growth among U.S., term, singleton neonates were not explained by trends in maternal and neonatal characteristics, changes in obstetric practices, or concurrent decreases in gestational length.

LEVEL OF EVIDENCE

III.

Variation in child cognitive ability by week of gestation among healthy term births

The authors investigated variations in cognitive ability by gestational age among 13,824 children at age 6.5 years who were born at term with normal weight, using data from a prospective cohort recruited in 1996-1997 in Belarus. The mean differences in the Wechsler Abbreviated Scales of Intelligence were examined by gestational age in completed weeks and by fetal growth after controlling for maternal and family characteristics. Compared with the score for those born at 39-41 weeks, the full-scale intelligence quotient (IQ) score was 1.7 points (95% confidence interval (CI): -2.7, -0.7) lower in children born at 37 weeks and 0.4 points (95% CI: -1.1, 0.02) lower at 38 weeks after controlling for confounders. There was also a graded relation in postterm children: a 0.5-points (95% CI: -2.6, 1.6) lower score at 42 weeks and 6.0 points (95% CI: -15.1, 3.1) lower at 43 weeks. Compared with children born large for gestational age (>90th percentile), children born small for gestational age (<10th percentile) had the lowest IQ, followed by those at the 10th-50th percentile and those at the >50th-90th percentile. These findings suggest that, even among healthy children born at term, cognitive ability at age 6.5 years is lower in those born at 37 or 38 weeks and those with suboptimal fetal growth.

Thyroid function in term and late preterm infants with respiratory distress in relation to severity of illness

BACKGROUND

Transient hypothyroxinemia is common in extremely premature infants, but has not been extensively investigated in ill term and late preterm infants. We hypothesized that free thyroxine (T(4)) levels in term and late preterm infants with respiratory distress would be inversely related to severity of illness

METHODS

Eligible infants included those had > or =35 weeks of gestation requiring mechanical ventilation or nasal continuous positive airway pressure. Thyroid function (thyroid-stimulating hormone, T(4), free T(4) [fT(4)], and free triiodothyronine) and cortisol levels were collected at four specified intervals (birth, day 2, day 3, and day 5 of life). Illness severity was measured using score for neonatal acute physiology (SNAP). Infants with an SNAP > or =10 were considered to have severe illness. Statistical analysis included repeated measures analysis of variance.

RESULTS

A total of 20 patients were enrolled in the study. The mean gestational age of study infants was 37.0 +/- 1.7 weeks. Infant with SNAP > or =10 had a diminished thyroid-stimulating hormone at birth. There was an inverse correlation between SNAP at birth and fT(4.) There was also an inverse correlation between lowest measured fT(4) and highest mean airway pressure, oxygenation index, and A-a gradient. Infants who received inhaled nitric oxide had diminished fT(4) levels compared to infants who did not receive this therapy. There were no differences in cortisol in those infants with and without SNAP > or =10 during the study period.

CONCLUSIONS

In our study sample, there was an association between severity of illness and fT(4) levels at birth, and infants requiring inhaled nitric oxide showed decreased fT(4) over the study time. Further research is warranted to determine whether T(4) supplementation would be beneficial in term and late preterm infants with respiratory distress.

Perinatal risk factors for early onset of Type 1 diabetes in a 2000-2005 birth cohort

AIMS

To examine perinatal risk factors for the onset of Type 1 diabetes before 6 years of age, in a 2000-2005 Australian birth cohort.

METHODS

Data from longitudinally linked delivery and hospital admission records (until June 2007) were analysed. Diabetes in mothers and children was identified from International Classification of Diseases 10 diagnosis codes in the hospital records.

RESULTS

There were 272 children admitted to hospital with a first diagnosis of diabetes out of 502 040 live births. Incidence for the infants born in 2000 was 16.0 per 100 000 person-years. Maternal Type 1 diabetes was a significant risk factor [crude relative risk (RR) 6.33], but maternal Type 2 diabetes and gestational diabetes were not significantly associated with diabetes in the child. Late preterm birth (34-36 weeks) (RR 1.64) and caesarean section (RR 1.30) increased the risk of a diabetes admission. Size-for-gestational-age was significantly associated with onset of diabetes (small-for-gestational age RR 0.48), but neither birth weight categories nor birth weight as a continuous variable were associated with risk of diabetes. Increasing maternal age was associated with an increased risk of diabetes in the child (RR 1.13 for each additional 5 years of age).

CONCLUSIONS

This study identified risk factors associated with onset of Type 1 diabetes before 6 years of age, in a recent birth cohort. Size-for-gestational-age had a consistent association with risk of early onset of Type 1 diabetes, small size being protective. Size-for-gestational-age measures should be preferred to birth weight thresholds when assessing risk of diabetes.

Visuospatial and verbal fluency relative deficits in 'complicated' late-preterm preschool children

BACKGROUND

Late-preterm children constitute a majority of all preterm deliveries (75%). Their immature brain development at birth has been associated with an increased risk for morbidities. Data have been sparse regarding neuropsychological outcomes in the preschool years.

AIM

To examine general cognition, attention/working memory, language, manual coordination/motor dexterity, visuomotor, visuospatial, and executive functions in preschoolers born late-preterm (LPT; 34-36 gestational weeks) who required NICU admission compared to term-born participants.

DESIGN

Single-center retrospective cohort study of 95 three-year-old children; 60 born LPT in 2004-2005 and admitted to the NICU compared to 35 healthy term-born participants born > or =37 gestational weeks and > or =2500 g.

RESULTS

LPT birth was associated with visuospatial (p=.005), visuomotor (p=.012), and executive function (noun [p=.018] and action-verb [p=.026] fluency) relative deficits, but not attention/working memory, receptive or expressive language, nonverbal reasoning, or manual coordination/dexterity deficit.

CONCLUSIONS

Late-preterm birth is likely to be associated with negative neuropsychological sequelae, although subtle and selective compared to effects reported for children born at an earlier gestational age. Visuospatial function appears to be especially vulnerable to disruption even at preschool age, and verbal fluency may be useful as an early predictor of executive dysfunction in childhood. Routine preschool neuropsychological evaluation is recommended to identify delay or deficit in LPT children preparing for school entry, and may highlight underlying vulnerable neural networks in LPT children.

Late preterm birth is a risk factor for growth faltering in early childhood: a cohort study

BACKGROUND

Rates of preterm birth are increasing worldwide and this increase is mostly due to infants born between 34 and 36 weeks of gestational age, the so-called "late preterm" births. The aim of this study was to assess the effect of late preterm birth over growth outcomes, assessed when children were 12 and 24 months old.

METHODS

In 2004, all births taking place in Pelotas (Southern Brazil) were recruited for a cohort study. Late preterm (34/0-36/6 weeks of gestational age) and term children (37/0-42/6 weeks) were compared in terms of weight-for-age, length-for-age and weight-for-length z-scores. Weight-for-age, length-for-age and weight-for-length z-scores below -2 were considered, respectively, underweight, stunting and wasting. Singleton newborns with adequate weight for gestational age at birth, successfully followed-up either at 12 or 24 months of age were analyzed and adjusted odds ratios with 95% confidence intervals calculated through logistic regression.

RESULTS

3285 births were included, 371 of whom were late preterm births (11.3%). At 12 months, prevalence of underweight, stunting and wasting were, respectively, 3.4, 8.7 and 1.1% among late preterm children, against 1.0, 3.4 and 0.3% among term children. At 24 months, correspondent values were 3.0, 7.2 and 0.8% against 0.8, 2.9 and 0.4%. Comparing with the term children, adjusted odds of being underweighted among late preterm children was 2.57 times higher (1.27; 5.23) at 12 months and 3.36 times higher (1.56; 7.23) at 24; of being stunted, 2.35 (1.49; 3.70) and 2.30 (1.40; 3.77); and of being wasted, 3.98 (1.07; 14.85) and 1.87 (0.50; 7.01). Weight gain from birth to 12 and 24 months was similar in late preterm and term children, whereas length gain was higher in the former group in both periods.

CONCLUSION

Late preterm children grow faster than children born at term, but they are at increased risk of underweight and stunting in the first two years of life. Failure to thrive in the first two years may put them at increased risk of future occurrences of serious morbidity in late childhood and of chronic disease development in adult life.

Trends in preterm births in Flanders, Belgium, from 1991 to 2002

Changes in the preterm birth rate have been attributed predominantly to increases in multiple pregnancies, associated with advanced maternal age and assisted reproduction, and to obstetric intervention. We examined their contribution to the frequencies of preterm (<37 weeks), very preterm (<32 weeks) and severely preterm (<28 weeks) birth among 700 383 singleton and twin births in Flanders from 1991 to 2002. We examined changes across four 3-year periods (triennia) with confidence interval [CI] analysis and yearly incremental rates using linear and logistic regression analyses. Over the 12 years, twin pregnancies increased from 1.5% to 2.0%, averaging 1.6% [95% CI 1.54, 1.66] in 1991-93 and 1.9% [95% CI 1.81, 1.94] in 2000-02 (P < 0.001). The proportion of women aged 35 years or more increased from 6.8% [95% CI 6.69, 6.92] in 1991-93 to 11.3% [95% CI 11.2, 11.5] in 2000-02 (P < 0.001) and those aged under 20 from 1.9% [95% CI 1.81, 1.93] to 2.3% [95% CI 2.26, 2.41] (P < 0.001). Assisted reproduction increased from 2.6% [95% CI 2.48, 2.62] to 4.2% [95% CI 4.11, 4.30] (P < 0.001) and obstetric intervention to end pregnancy from 36.2% [95% CI 36.0, 36.4] to 40.3% [95% CI 40.1, 40.6] (P < 0.001). These increases related to an annual increase of 0.23% in the preterm birth rate from 5.5% [95% CI 5.4, 5.6] in 1991-93 to 7.2% [95% CI 7.1, 7.3] in 2000-02 (P < 0.001). The proportions of very and severely preterm births also increased by nearly a third, but their contribution to the total preterm birth rate remained stable at 15% and 5%, respectively. Odds ratios for the increases per year were 1.035 [95% CI 1.032, 1.038] for preterm birth, 1.024 [95% CI 1.018, 1.031] for very preterm and 1.028 [95% CI 1.017, 1.040] for severely preterm births after adjusting for other changes in the population. Overall, the data show, first, marked increases in the frequency of known contributors to the preterm birth rate, including twin pregnancies, advanced maternal age, assisted reproduction and obstetric intervention. Second, the preterm birth rate further increased significantly within subgroups of women with one or more of these characteristics. Third, the preterm birth rate also rose, from 4.4% [95% CI 4.2, 4.5] in 1991-93 to 5.6% [95% CI 5.5, 5.8] in 2000-02 (P < 0.001), in women with none of these contributing factors. This indicates that changes in the frequency of these known predictors are insufficient to explain the steady increase in preterm, very preterm and severely preterm births over more than a decade.

Prenatal corticosteroid prophylaxis for women delivering at late preterm gestation

OBJECTIVE

We studied patterns of prenatal corticosteroid use, respiratory distress syndrome, and associated mortality rates to assess the congruence between knowledge and clinical practice related to such prophylaxis.

METHODS

We used data on all live births in the United States (for the years 1989-1991, 1995-1997, and 2002-2004) and Nova Scotia, Canada (for the years 1988-2007). Gestational age-specific temporal trends in infant deaths resulting from respiratory distress syndrome were quantified in the United States, and gestational age-specific temporal trends in corticosteroid use and morbidity (respiratory distress syndrome and intraventricular hemorrhage) were quantified in Nova Scotia.

RESULTS

In the United States, infant deaths associated with respiratory distress syndrome decreased by 48% (95% confidence interval: 46%-50%) from 1989-1991 to 1995-1997 and then decreased by another 18% (95% confidence interval: 15%-22%) by 2002-2004. The latter mortality reduction was evident at 28 to 32 weeks but not 33 to 36 weeks of gestation. Corticosteroid use at 28 to 32 weeks was high in Nova Scotia and increased from 30.7% in 1988-1989 to 50.0% in 1996-1997 and to 52.9% in 2006-2007, whereas rates of use at 33 to 36 weeks were much lower (eg, 6.7%, 17.0%, and 15.7% at 34 weeks in the 3 periods). Increased corticosteroid use at 33 and 34 weeks was estimated to reduce respiratory distress syndrome substantially.

CONCLUSION

Addressing the knowledge-practice gap in corticosteroid use at 33 to 34 weeks should reduce infant morbidity and mortality rates.

Late preterm birth: how often is it avoidable?

OBJECTIVE

Our objective was to describe indications for late preterm birth (LPTB) and estimate the frequency of potentially avoidable LPTB deliveries.

STUDY DESIGN

Singleton pregnancies delivered between 34(0/7)-36(6/7) weeks over a 1-year period at a tertiary care medical center were studied. Indications for delivery were categorized as spontaneous (spontaneous preterm birth or premature rupture of membranes) or iatrogenic (elective or medically indicated). Potentially avoidable deliveries were defined as those with elective or medical stable, but high-risk indications.

RESULTS

During the study period there were 514 LPTB (spontaneous preterm birth 36.2%, preterm premature rupture of membranes 17.7%, medically indicated 37.9%, and elective 8.2%). Potentially avoidable LPTB accounted for 17% of LPTB and were associated with later gestational age (odds ratio [OR], 4.7; 95% confidence interval [CI], 2.5-8.6), nonfaculty physician status (OR, 2.8; 95% CI, 1.5-5.1), and prior cesarean delivery (OR, 1.5; 95% CI, 1.0-2.1).

CONCLUSION

At our institution, <10% of LPTB are purely elective and >80% are clearly unavoidable.

Outcomes of late-preterm infants: a retrospective, single-center, Canadian study

OBJECTIVE

To study the prevalence of major morbidities and mortality of inborn, late-preterm infants. Methods. A retrospective review was conducted from 2004 to 2008. Descriptive outcomes were compared with predefined aggregate outcomes of term infants during the same period.

RESULTS

Data on 1193 late-preterm and 8666 term infants were compared. Majority of late-preterm infants were 36 weeks (43.6%), followed by 35 weeks (29.2%) and 34 weeks (27.2%), respectively. The prevalence of intensive care admission, respiratory support, pneumothorax, and mortality in late preterm infants was significantly higher compared with term infants. Mechanical ventilation and continuous positive airway pressure rates substantially decreased with increased gestational age. Although only 1.0% had positive cultures, 28.5% received parenteral antibiotics. The late-preterm group had a 12-fold higher risk of death with an overall mortality rate of 0.8%.

CONCLUSION

This study confirmed the high-risk status of late-preterm infants with worse mortality and morbidities compared with term infants.

So, he's a little premature...what's the big deal?

Health care providers have recently recognized that a large segment of the morbidity associated with preterm birth is disproportionately due to the late preterm infant (LPI). One explanation is that this population is the fastest-growing sector of all preterm births. This article describes the epidemiology and etiology of the LPI, and discusses why the LPI is at an increased risk for complications, such as thermal instability, hypoglycemia, feeding difficulties, respiratory distress, hyperbilirubinemia, and sepsis. The need for emergency department visits after hospital discharge and what is currently known regarding neurodevelopmental outcomes are also presented.

Screening for severe neonatal hyperbilirubinemia

Screening for severe neonatal hyperbilirubinemia is integral to newborn care. Predischarge risk assessment relies on documentation of visual jaundice: age at onset and progression; identification of clinical risk such as late prematurity and bruising; with determination of total bilirubin (blood or transcutaneous assay) adjusted for age in hours. Along with promotion of breastfeeding, coordination between birthing hospital and medically supervised outpatient follow-up, a systems approach allows for a safer and effective means to prevent adverse effects of extreme hyperbilirubinemia.

[Late preterm infants: A population at underestimated risk]

BACKGROUND AND OBJECTIVE

There has been a gradual rise in prematurity rates recent years, almost exclusively at the expense of the late preterm (34 to 36 weeks). This population, although with less risk than smaller preterm gestational age, has a morbidity rate significantly higher than term infants. However, there is some underestimation regarding developments in the short and long term. The aim of this study was to look at the incidence of prematurity in our institution and to analyze morbidity and mortality in late preterm compared with term infants

SUBJECTS AND METHODS

We performed a retrospective review of newborns in our Hospital from January 1992 until December 31, 2008. Late preterm group was defined as between 34(0/7) and 36(6/7) weeks gestation (N=2003) and term infants from 37 to 42 weeks gestation (N=32015). We formed 2 subgroups according two time periods (1992-1998 and 2000-2008). The morbidity and mortality for each of the groups and subgroups, and the morbidity from week 34 to 42, were analysed and compared.

RESULTS

During the period studied, the prematurity rate increased from 3.9% to 9.8%, exclusively at the expense of the late preterm (79%). The rate of mortality in late preterm was 5 per thousand compared to 1.1 per thousand in the term (P <0.0001, OR 4.71, 95% CI 2.3-9.5). The incidence of admission to the Neonatal Unit, Cesarean rate, twin, respiratory disorders, need for respiratory support in the form of nasal CPAP or mechanical ventilation, incidence of apnea, jaundice requiring phototherapy, hypoglycaemia and need for parenteral nutrition were significantly higher (P<0.0001) in the late preterm group compared with term infants. The morbidity rate decreased significantly as gestational age increased, with the lowest value from 39 weeks.

CONCLUSIONS

Morbidity and mortality in late preterm infants is significantly higher than in term infants. The guidelines for these near term premature babies need to be reviewed, looking for possible causes of prematurity, and trying to reduce their impact, as well as developing a protocol for their care and close monitoring to minimize the associated morbidity. There should be long-term monitoring to find out the consequences on their psychomotor development. The obstetrics group should be made aware of the true risks of births in the near-term gestational ages.

Association of genetic ancestry with preterm delivery and related traits among African American mothers

OBJECTIVE

In the United States, the rate of preterm delivery (PTD) is higher in African Americans (17.8%) than non-Hispanic whites (11.5%). Such disparity cannot be fully explained by differences in socioenvironmental factors.

STUDY DESIGN

We genotyped 812 mothers in a case-control PTD study at Boston Medical Center who self-reported their ethnicity as "black." Regression analysis and Wilcoxon rank-sum test were applied to evaluate ancestral distribution and the association between genetic ancestry and PTD-related traits, as well as the potential confounding effect of population stratification.

RESULTS

The estimated African ancestral proportion was 0.90 +/- 0.13. We found significant associations of ancestral proportion with PTD as a whole and PTD subgrouped by the presence of maternal hypertensive disorders. We did not observe significant confounding as a result of population stratification in this case-control PTD study.

CONCLUSION

Our data underline the need for more intensive investigation of genetic admixture in African Americans to identify novel susceptibility genes of PTD.

Long-term development of low-risk low birth weight preterm born infants: neurodevelopmental aspects from childhood to late adolescence

BACKGROUND

Most studies on clinical outcome of preterm born infants focus on high-risk infants, whereas little is known about the long-term prognosis of low-risk low birth weight preterm born infants (LBW).

AIMS

To examine physical growth, school outcome, behavioural aspects, quality of life, and intervention impact on LBW in late adolescence compared to term born controls and to analyse developmental pathways from childhood to adolescence for these groups.

STUDY DESIGN

In late adolescence 65 LBW and 41 matched term born controls were assessed with a structured telephone interview and standardized questionnaires with regard to physical growth, school career, therapeutic interventions, behavioural aspects, and quality of life. Longitudinal analysis comprised data from birth, infancy, school age, and adolescence.

RESULTS

Growth in height of LBW was highly variable, but correlated significantly with birth parameters and was below those of controls with regard to percentiles. School enrollment of LBW was more often delayed, and there was a trend toward lower school graduation in LBW. The groups did not differ with regard to general or health-related quality of life and behavioural aspects, but LBW received significantly more therapeutical interventions.

CONCLUSIONS

In general, LBW showed no major deficits in late adolescence. However, a prolonged school career and a higher demand for therapeutic interventions indicate subtle neurodevelopmental deficits in LBW. This underscores the need for professional follow-up programmes for this majority of preterm born infants.

Neurodevelopmental outcome of the premature infant

Advances in antenatal medicine and neonatal intensive care have successfully resulted in improved survival rates of preterm infants. These improvements have been most dramatic in infants born extremely low birth weight (ELBW, <or=1000 g) and at the limits of viability (22 to 25 weeks). But improvements in survival have not been accompanied by proportional reductions in the incidence of disability in this population. Thus, survival is not an adequate measure of success in these infants who remain at high risk for neurodevelopmental and behavioral morbidities. There is now increasing evidence of sustained adverse outcomes into school age and adolescence, not only for ELBW infants but for infants born late preterm.

Health issues of the late preterm infant

"Late preterm" birth is not such an unusual occurrence; in fact these infants were the first group of premature infants who pediatricians learned to treat, and did so with such remarkable success that physicians no longer consider them to be of high risk. So, why the sudden interest in this group? There is now enough evidence that this population is not as benign as previously thought. They have increased mortality when compared to term infants and are at increased risk for complications including transient tachypnea of newborn (TTN), respiratory distress syndrome (RDS), persistent pulmonary hypertension (PPHN), respiratory failure, temperature instability, jaundice, feeding difficulties and prolonged neonatal intensive care unit (NICU) stay. Evidence is currently emerging that late preterm infants make up a majority of preterm births, take up significant resources, have increased mortality/morbidity, and may even have long-term neurodevelopmental consequences secondary to their late prematurity.

Optimizing successful breastfeeding in the newborn

PURPOSE OF REVIEW

The purpose of this article is to present an overview of the state of breastfeeding in the United States and to examine recent evidence for strategies aimed at optimizing successful breastfeeding in the neonatal period.

RECENT FINDINGS

Although rates of any and exclusive breastfeeding are rising, American mothers and infants are still unable to meet the Healthy People 2010 objectives. A review of the current literature demonstrates that the 'Ten Steps to Successful Breastfeeding' and the Baby Friendly Hospital Initiative are effective measures to increase breastfeeding initiation, duration, and exclusivity. A recent national survey reveals a significant proportion of pediatricians are not providing evidence-based recommendations for breastfeeding guidance and support.

SUMMARY

The Baby Friendly Hospital Initiative, based upon the 'Ten Steps to Successful Breastfeeding', is an effective evidence-based model of perinatal care that protects, promotes, and supports breastfeeding. Pediatricians should aim to provide anticipatory guidance and management consistent with the 'Ten Steps' to optimize breastfeeding outcomes for mothers and their newborns.

Late preterm infants: severe hyperbilirubinemia and postnatal glucose homeostasis

The identification of late preterm infants as a high-risk group of infants has been an important public health breakthrough. These infants have suffered a relative 'silent morbidity and mortality' before the recognition that they have unique physiology and risks. These infants represent almost three-fourths of all premature births in the United States. Many of these infants, because of their birthweight and appearance, have been treated in Well Baby Nurseries and even discharged by 48 h of birth despite specific unidentified or unappreciated risks that have led to their readmission and possible severe morbidities or even death. Two common problems for these infants include neonatal hypoglycemia and severe hyperbilirubinemia. The definition of hypoglycemia remains controversial but is nonetheless a problem of increasing frequency in these infants.

Indications for delivery and short-term neonatal outcomes in late preterm as compared with term births

OBJECTIVE

The objective of the study was to evaluate the indications for late preterm birth and compare outcomes by gestational age among late preterm (34-36 weeks) and term (> or = 37 weeks) neonates at our institution.

STUDY DESIGN

This was a retrospective analysis of delivery indications and short-term neonatal outcomes in women who delivered at the University Hospital between January 1, 2005 and Dec. 31, 2006. Data were analyzed using chi(2), Student's t-test, analysis of variance, and post hoc Tukey tests.

RESULTS

One hundred forty-nine late preterm (n = 49 for 34, n = 50 for 35, n = 50 for 36 weeks) and 150 term infants (n = 50 for 37, n = 50 for 38, n = 50 for 39 weeks or longer) were evaluated. Differences among groups (ie, 34 vs 35 vs 36 vs 37, etc) as well as combinations of differences between 2 groups (ie, 34-36 weeks vs > or = 37 or > or = 38 weeks) were analyzed. Spontaneous labor and/or rupture of membranes were the most common indications for late preterm delivery (92%). Compared with term, late preterm infants had longer hospital stays (5 days vs 2.4 days; P < .001) and higher rates of neonatal intensive care unit (NICU) admissions (56% vs 4%; P < .001), feeding problems (36% vs 5%; P < .001), hyperbilirubinemia (25% vs 3%; P < .001), and respiratory complications (20% vs 5%; P < .001). Neonatal complications were minimal at 38 weeks or longer.

CONCLUSION

Rates of neonatal intensive care unit admission, length of stay, and neonatal morbidities are significantly higher in late preterm as compared with term births.

Admission of all gestations to a regional neonatal unit versus controls: neonatal morbidity

AIMS

To describe the neonatal course and morbidity of all infants admitted to the regional neonatal intensive care unit (NICU) at Christchurch Women's Hospital (CWH) and to compare these with term control infants who were not admitted, in one calendar year. Infants in both NICU and control cohorts were enrolled in a 2-year follow-up study.

METHODS

All infants born over a 12-month period from February 2001 and admitted to the NICU, whose parents were domiciled in a defined geographical region, were eligible for study, together with every eighth healthy infant born at term and not admitted (to a total of 300). Comprehensive perinatal and neonatal data were collected for all enrolled infants.

RESULTS

A total of 387 NICU infants (86% eligible) were enrolled in the study together with 306 controls. Forty-one percent of NICU admissions were term and 40% were 33-36 weeks gestation. Term NICU infants were more likely to be born following induction of labour or by Caesarean section (34%, of which 50% were pre-labour) than control infants (18%, of which 32% were pre-labour). Infants of <28, 28-32, 33-36 and > or =37 weeks accounted for 74, 16, 7 and 3% of assisted ventilation days and 18, 31, 31 and 20% of total baby days, respectively.

CONCLUSIONS

The need for assisted ventilation and length of NICU stay was inversely proportional to gestation. However, preterm infants of 28 weeks gestation and greater, as well as term infants, account for a high proportion of the NICU workload.

Early school-age outcomes of late preterm infants

OBJECTIVE

Late preterm infants represent a significant portion of preterm deliveries. Until recently, these infants have received little attention because of assumptions that they carry minimal risk for long-term morbidities. The purpose of this study was to compare prekindergarten and kindergarten outcomes among healthy late preterm infants, 34 0/7 to 36 6/7 weeks' gestation at birth, and healthy term infants, 37 0/7 to 41 6/7 weeks' gestation at birth.

METHODS

The study sample consisted of singleton infants who were born in Florida between January 1, 1996, and August 31, 1997, with a gestational age between 34 and 41 weeks (N = 161804) with a length of stay < or =72 hours. Seven early school-age outcomes were analyzed. Outcomes were adjusted for 15 potential confounding maternal and infant variables. Unadjusted and adjusted relative risk with 95% confidence interval was estimated for each outcome by using Poisson regression modeling.

RESULTS

Risk for developmental delay or disability was 36% higher among late preterm infants compared with term infants. Risk for suspension in kindergarten was 19% higher for late preterm infants. The remaining 4 outcomes, disability in prekindergarten at 3 and 4 years of age, exceptional student education, and retention in kindergarten, all carried a 10% to 13% increased risk among late preterm infants. The assessment "not ready to start school" was borderline significant.

CONCLUSIONS

This study suggests that healthy late preterm infants compared with healthy term infants face a greater risk for developmental delay and school-related problems up through the first 5 years of life.

Admissions of all gestations to a regional neonatal unit versus controls: 2-year outcome

AIMS

To assess neurodevelopmental outcome at 2 years for neonatal intensive care unit (NICU) admissions compared with controls, and to trial a parent-reporting scheme.

METHODS

All infants admitted to the NICU at Christchurch Women's Hospital over a 12-month period and whose parents were domiciled in a defined geographical region were eligible for study, together with every eighth term infant not admitted (to a total of 300). Parents completed a two-page questionnaire on their child's 2nd birthday. All infants <28 weeks gestation and a random 300 NICU admissions and 108 controls underwent a paediatric examination and Bayley II assessment at 2 years of age.

RESULTS

A total of 387 NICU infants (86% eligible) and 306 controls were enrolled. At 2 years of age, 276 NICU infants (89% survivors) and 94 controls (87%) had some follow up. For infants of <33 weeks, 33-36 weeks, > or =37 weeks gestation and controls, the percentage >1 SD below the mean on the Bayley Mental Development Index scales were 33.3, 36.5, 44.6 and 24.1, respectively (P= 0.03); on the Psychomotor Developmental Index scales were 30.0, 29.1, 41.1 and 19.5 (P= 0.02) and the percentage with any cerebral palsy were 11.1, 2.8, 5.2 and 1.2.

CONCLUSIONS

At 2 years of age, NICU graduates have more developmental problems than controls across a range of measures. In many cases, term NICU graduates have the least favourable outcome. There was only moderate agreement between parents' reporting of moderate or severe developmental disability by means of a questionnaire, compared with professionals (kappa statistic 0.38), with parents tending to underestimate problems.

Impact of cesarean section on intermediate and late preterm births: United States, 2000-2003

BACKGROUND

Cesarean section appears to be associated with increased risk of neonatal mortality among infants of low-risk term pregnancies, but it may offer some survival advantage among the most extremely preterm infants. The impact on intermediate (32-33 wk) and late preterm (34-36 wk) deliveries remains uncertain. The objective of this analysis was to compare the neonatal mortality rate (death at 0-27 days), the mechanical ventilation usage rate, and the incidence of hyaline membrane disease among intermediate and late preterm infants delivered by primary cesarean section compared with those delivered vaginally.

METHODS

United States Linked Birth and Infant Death Certificate files from the years 2000 to 2003 were used. Maternal demographic characteristics, medical complications, and labor and delivery complications were abstracted from the files along with infant information. Because of concern for misclassification of gestational age, a procedure was used to trim away births in which the birthweight of an infant for a specific gestational age was inconsistent. Adjusted odds ratios were calculated using logistic regression for the risk of the three outcomes of interest relative to the mode of delivery.

RESULTS

A total of 422,001 live births were available with complete data from the trimmed data set (60% of untrimmed data). After adjustment by logistic regression for infant size at birth, birthweight, sex, Apgar score at 5 minutes less than 4, multiple births, breech presentation, presence of an anomaly, the presence of any maternal medical condition or complication of labor and delivery, labor induction, maternal race, age, education, and gravidity, the adjusted odds ratios (95% CI for neonatal mortality at gestational ages of 32, 33, 34, 35, and 36 wk) were, respectively, 1.69 (1.31-2.20), 1.79 (1.40-2.29), 1.08 (0.83-1.40), 2.31 (1.78-3.00), and 1.98 (1.50-2.62).

CONCLUSIONS

These data suggest that for low-risk preterm infants at 32 to 36 weeks' gestation, independent of any reported risk factors, primary cesarean section may pose an increased risk of neonatal mortality and morbidity.

Early rapid growth, early birth: accelerated fetal growth and spontaneous late preterm birth

The past two decades in the United States have seen a 24% rise in spontaneous late preterm delivery (34-36 weeks) of unknown etiology. This study tested the hypothesis that fetal growth was identical prior to spontaneous preterm (n = 221, median gestational age at birth 35.6 weeks) and term (n = 3706) birth among pregnancies followed longitudinally in Santiago, Chile. The hypothesis was not supported: Preterm-delivered fetuses were significantly larger than their term-delivered peers by mid-second trimester in estimated fetal weight, head, limb, and abdominal dimensions, and they followed different growth trajectories. Piecewise regression assessed time-specific differences in growth rates at 4-week intervals from 16 weeks. Estimated fetal weight and abdominal circumference growth rates slowed at 20 weeks among the preterm-delivered, only to match and/or exceed their term-delivered peers at 24-28 weeks. After an abrupt growth rate decline at 28 weeks, fetuses delivered preterm did so at greater population-specific sex and age-adjusted birth weight percentiles than their peers from uncomplicated pregnancies (P < 0.01). Growth rates predicted birth timing: one standard score of estimated fetal weight increased the odds ratio for late preterm birth from 2.8 prior to 23 weeks, to 3.6 (95% confidence interval, 1.82-7.11, P < 0.05) between 23 and 27 weeks. After 27 weeks, increasing size was protective (OR: 0.56, 95% confidence interval, 0.38-0.82, P = 0.003). These data document, for the first time, a distinctive fetal growth pattern across gestation preceding spontaneous late preterm birth, identify the importance of mid-gestation for alterations in fetal growth, and add perspective on human fetal biological variability.

Breastfeeding the late preterm infant

Late preterm infants comprise the fastest growing segment of babies born prematurely. They arrive with disadvantages relative to feeding skills, stamina, and risk for conditions such as hypoglycemia, hyperbilirubinemia, and slow weight gain. Breastfeeding these babies can be difficult and frustrating. Individualized feeding plans include special considerations to compensate for immature feeding skills and inadequate breast stimulation. Breastfeeding management guidelines are described that operate within the late preterm infant's special vulnerabilities.

Development of the forward parachute reaction and the age of walking in near term infants: a longitudinal observational study

BACKGROUND

Near term infants are a main part of preterms. They are at higher risk for mortality and morbidity than term infants and could show a quite different development of tone and reflexes from them. The aim of the present study was to describe longitudinally, in a large sample of healthy near term infants, the development of the forward parachute reaction (FPR) and its correlation with the age of acquisition of independent walking.

METHODS

The assessment of FPR (as absent, incomplete or complete) was performed at 3, 6, 9, 12 months of corrected age in 484 infants, with a gestational age between 35.0 and 36.9 weeks. The age of acquisition of independent walking was monitored until its appearance. A correlation analysis was done between the age of walking and the acquisition of a complete or incomplete FPR, using the Spearman Rank correlation. The Mann-Withney U test was used to identify significant gestational age differences for the age of FPR appearance.

RESULTS

Most of infants had a two-step development pattern. In fact, they showed at first an incomplete and then a complete FPR, which was observed more frequently at 9 months. An incomplete FPR only, without a successive maturation to a complete FPR, was present in the 21% of the whole sample. Infants with a complete FPR walked at a median age of 13 months, whereas those with an incomplete FPR only walked at a median age of 14 months.

CONCLUSION

We identified two groups within our sample of near term infants. The first group showed a progressive maturation of FPR, whereas the second one was characterised by the inability to get a complete pattern, within the one year observation's period. Furthermore, we observed a trend toward a delayed acquisition of independent walking in the latter group of infants.

Increased risk of adverse neurological development for late preterm infants

OBJECTIVE

To assess the risks of moderate prematurity for cerebral palsy (CP), developmental delay/mental retardation (DD/MR), and seizure disorders in early childhood.

STUDY DESIGN

Retrospective cohort study using hospitalization and outpatient databases from the Northern California Kaiser Permanente Medical Care Program. Data covered 141 321 children > or =30 weeks born between Jan 1, 2000, and June 30, 2004, with follow-up through June 30, 2005. Presence of CP, DD/MR, and seizures was based on International Classification of Diseases, Ninth Revision codes identified in the encounter data. Separate Cox proportional hazard models were used for each of the outcomes, with crude and adjusted hazard ratios calculated for each gestational age group.

RESULTS

Decreasing gestational age was associated with increased incidence of CP and DD/MR, even for those born at 34 to 36 weeks gestation. Children born late preterm were >3 times as likely (hazard ratio, 3.39; 95% CI, 2.54-4.52) as children born at term to be diagnosed with CP. A modest association with DD/MR was found for children born at 34 to 36 weeks (hazard ratio, 1.25; 95% CI, 1.01-1.54), but not for children in whom seizures were diagnosed.

CONCLUSIONS

Prematurity is associated with long-term neurodevelopmental consequences, with risks increasing as gestation decreases, even in infants born at 34 to 36 weeks.

Persistence of morbidity and cost differences between late-preterm and term infants during the first year of life

BACKGROUND

Late-preterm infants are known to have greater morbidity and costs compared with term infants during the neonatal period, but less is known about whether these differences continue beyond this period.

OBJECTIVE

The purpose of this study was to examine the most common causes and costs of rehospitalization and other health care use among late-preterm and term infants throughout the first year of life.

METHODS

We conducted a retrospective cohort study of late-preterm (33-36 weeks' gestation) and term infants born in 2004 with > or =1 year of enrollment in a large national US database of commercially insured members. All of the reported health care services and costs were examined from the birth hospitalization through the first year of life.

RESULTS

We evaluated 1683 late-preterm and 33 745 term infants. The average length of stay of the birth hospitalization for term infants was 2.2 days, and the average cost was $2061. Late-preterm infants had a substantially longer average stay of 8.8 days and average cost of $26 054. Total first-year costs after birth discharge were, on average, 3 times as high among late-preterm infants ($12 247) compared with term infants ($4069). Late-preterm infants were rehospitalized more often than term infants (15.2% vs 7.9%). A subset of late-preterm infants that were discharged late from their birth hospitalization had the highest rates of rehospitalization and total health care costs. Higher costs during rehospitalization of late-preterm infants, especially those with a late discharge, indicate their propensity to have more severe illness.

CONCLUSIONS

Late-preterm infants have greater morbidity and total health care costs than term infants, and these differences persist throughout the first year of life. Management strategies and guidelines to reduce morbidity and costs in late-preterm infants should be investigated.

Neonatal and maternal outcomes associated with elective term delivery

OBJECTIVE

To quantify adverse neonatal and maternal outcomes associated with elective term delivery at less than 39 completed weeks of gestation.

STUDY DESIGN

Prospective observational study conducted in 27 hospitals over the course of 3 months in 2007.

RESULTS

Of 17,794 deliveries, 14,955 (84%) occurred at 37 weeks or greater. Of term deliveries, 6562 (44%) were planned, rather than spontaneous. Among the planned deliveries, 4645 (71%) were purely elective; 17.8% of infants delivered electively without medical indication at 37-38 weeks and 8% of those delivered electively at 38-39 weeks required admission to a newborn special care unit for an average of 4.5 days, compared with 4.6% of infants delivered at 39 weeks or beyond (P < .001). Cesarean delivery rate in women undergoing induction of labor was not influenced by gestational age but was highly influenced by initial cervical dilatation and parity, ranging from 0% for parous women induced at 5 cm or greater to 50% for nulliparous women at 0 cm.

CONCLUSION

Elective delivery before 39 weeks' gestation is associated with significant neonatal morbidity. Initial cervical dilatation is highly correlated with cesarean delivery among women undergoing induction of labor in both nulliparous and parous women. Elective delivery before 39 completed weeks' gestation is inappropriate. Women contemplating elective induction at or beyond 39 weeks' gestation with an unfavorable cervix should be counseled regarding an increased rate of cesarean delivery.