eNeonatal Review Newsletter

November 2009: VOLUME 7, NUMBER 3

Problems of Late Pre-term Neonates

In this Issue...

The rapid rise in late pre-term births in the United States over the last 20 years has added substantially to the overall burden of prematurity and its consequences. Because of their lower relative morbidity, compared with the very pre-term, late pre-term infants have previously escaped attention and detailed follow-up. However, the sheer volume of infants delivered at this gestational age (ie, 34 0/7 to 36 6/7 weeks), as well as the clear increase in morbidities when children are born even a few weeks prematurely, warrants awareness and special consideration. Although a proportion of pre-term births are unavoidable, the rise in what are termed “medically indicated” pre-term births and other potentially preventable pre-term deliveries is of particular concern.

In this issue, we examine recent and ongoing trends in late pre-term births, and discuss the short- and long-term outcomes in this group of infants.

LEARNING OBJECTIVES

At the conclusion of this activity, participants should be better able to:

		Describe the etiology of late pre-term births

		Discuss the short-term morbidities associated with late pre-term delivery

		Evaluate the long-term outcomes of infants born in the late pre-term period

IMPORTANT CME/CNE INFORMATION

Program Begins Below


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THIS ISSUE

		IN THIS ISSUE

		COMMENTARY from our Guest Authors

		EPIDEMIOLOGY AND ETIOLOGY OF LATE PRE-TERM BIRTH

		SHORT-TERM MORBIDITIES AND MORTALITY IN LATE PRE-TERM INFANTS

		THE IMPACT OF WEIGHT AND GESTATIONAL AGE ON MORTALITY IN LATE PRE-TERM INFANTS

		DOES THE ETIOLOGY OF LATE PRE-TERM DELIVERY IMPACT NEONATAL OUTCOME?

		LATE PRE-TERM INFANTS IN EARLY CHILDHOOD AND AT SCHOOL AGE

		FINANCIAL IMPACT OF THE CARE OF LATE PRE-TERM INFANTS IN EARLY CHILDHOOD

Program Directors

Edward E. Lawson, MD
Professor of Pediatrics
Johns Hopkins University
School of Medicine
Chief, Division of Neonatology
Vice Chair, Department of Pediatrics
Johns Hopkins Children's Center

Christoph U. Lehmann, MD
Associate Professor
Department of Pediatrics
Division of Neonatology
The Johns Hopkins University
School of Medicine

Lawrence M. Nogee, MD
Professor
Department of Pediatrics
Division of Neonatology
The Johns Hopkins University
School of Medicine

Mary Terhaar, DNSc, RN
Assistant Professor
Undergraduate Instruction
The Johns Hopkins University
School of Nursing

Anthony Bilenki, MA, RRT
Technical Director
Respiratory Care Services
Division of Anesthesiology and Critical Care Medicine
The Johns Hopkins Hospital
Baltimore, Maryland

GUEST AUTHORS OF THE MONTH

		Commentary & Reviews
		Lucky Jain, MD, MBA Richard W. Blumberg Professor Executive Vice Chairman Department of Pediatrics and Physiology Emory University School of Medicine and Children’s Healthcare of Atlanta Atlanta, Georgia

		Reviews
		Sarah Keene MD Assistant Professor Pediatrics (Neonatology) Department of Pediatrics and Physiology Emory University School of Medicine and Children’s Healthcare of Atlanta Atlanta, Georgia

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Dr. Jain does not have any relevant financial relationships to disclose.

Dr. Keene does not have any relevant financial relationships to disclose.

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The authors do not reference the off-label use of any drugs or procedures in this publication.

Program Directors' Disclosures

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In this podcast, Drs Lucky Jain and Sarah Keene present and discuss three case studies involving the delivery and clinical management of late pre-term neonates. Some of the topics include: the circumstances surrounding the increasing rate of pre-term births in the US, the indications for pre-term deliveries, and how to improve neonatal outcomes.

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COMMENTARY

Higher morbidity in “near-term” infants delivered electively even a few days earlier than the recommended 39 to 41 weeks’ gestation¹ lends strong support to what physiologists have believed all along: Rapid maturation of the fetus in the days leading up to normal spontaneous delivery plays a critical role in fetal transition to extrauterine life.² Lack of spontaneous labor appears to compound this problem; this, too, would appear to be a given to physiologists, since a huge perinatal surge in steroids and catecholamines is related directly to the onset (and propagation) of spontaneous labor.³ These endogenous hormone groups lead to rapid transcriptional and translational changes in cellular processes that facilitate events critical to transition, such as fetal lung fluid clearance. To a student of perinatal physiology, then, it would appear quite paradoxical to see the rapid rise in “near-term” infants, and an even more impressive rise in term and near-term infants who have never experienced labor.^4,5 Several factors have contributed to the rise in late pre-term births. There has been a rapid increase in obstetrical interventions, such as continuous fetal monitoring, labor inductions, and elective cesarean sections. Multiple pregnancies are on the rise as well, and these are much more likely to result in pre-term delivery. Efforts to prevent stillbirths may have also contributed to this situation, since the risk for in utero demise increases with each passing week as we approach term and post-term gestations. Unbeknown to the physiologist, however, this trend is also paralleled by an equally impressive decline in the rate of stillbirths.⁶ Some have argued that the transient health issues of near-term infants are more than offset by the number of in utero lives saved!

How, then, does one reconcile these opposing findings and trends that have the bearings of changing a paradigm in human reproduction established eons ago? In an effort to resolve this ongoing debate, in 2006 the National Institute of Child Health and Human Development (NICHD) convened a consensus conference, assembling experts from all related fields.⁷ “Late pre-term,” defined as births between 34 0/7 and 36 6/7 weeks, promptly replaced “near-term” births, to better reflect the physiologic vulnerabilities in this population.⁸ A major increase in the number of publications in this area has occurred since the meeting. These studies have allowed us to gain a better understanding of the epidemiology, pathophysiology, and clinical course of these infants. The articles chosen for review in this issue are representative of these areas.

The manuscripts reviewed, and the body of published work in this field, all appear to suggest that singleton infants born at late pre-term gestations are at a greater risk for perinatal mortality and morbidity than term infants. Compared with infants born at term, those delivered at late pre-term gestations have substantially higher risks for transient tachypnea, respiratory distress, hypoglycemia, pulmonary hypertension, and related complications.⁹ These complications are associated with an increase in neonatal intensive care unit (NICU) admissions, longer length of hospital stays, and a considerable drain on health care resources. Such infants also appear to have long-term neurologic sequelae, with some effects lasting well into early school age.¹⁰ Studies have shown a higher combined risk for acute neonatal morbidities leading to increased lengths of NICU stay and utilization of health care resources, combined with postneonatal morbidities and long-term care issues. These findings contradict the conventional wisdom that onset at the 34th week of gestation marks a physiologic watershed zone in fetal maturity. Such a belief is ingrained in the current standard of care, which calls for withholding tocolytics and antenatal steroids in mothers with pre-term labor at or after 34 weeks, and augmentation of labor for pre-term premature rupture of membranes (PROM); it also forms the basis for medically indicated pre-term births. However, the nearly 20% decrease in adverse neonatal outcomes with each advancing week of gestation between 32 and 39 weeks underscores the need for closer scrutiny of current obstetric practices.

Other outstanding issues remain unanswered: Are there ways to improve the outcomes of late pre-term deliveries that are deemed inevitable or medically necessary? Can standardized care paths improve outcomes? Are adverse neurologic outcomes secondary to in utero events that lead to pre-term delivery or to postnatal events that might be preventable? Since antenatal steroids are widely used before 34 weeks’ gestation and have had a considerable impact on outcomes, efforts are currently under way to investigate their role in late pre-term gestations. There is strong biologic plausibility for this intervention, since failure to clear lung fluid adequately is a major problem in this population and steroids have been shown to improve the process. Steroids are also likely to further enhance surfactant maturity.

Many centers have begun close monitoring of late pre-term infants before sending them off to their mothers’ rooms. Such monitoring includes temperature regulation, breathing rates and oxygen saturations, blood sugar levels, and the ability of the infant to coordinate suck and swallow. Clearly, these infants should not be let out of our sight until adequate feeding has been established. This is particularly important for first-time mothers and those experiencing difficulty with breastfeeding. Early follow-up with a pediatrician can further prevent morbidity and readmissions from poor feeding, dehydration, and hyperbilirubinemia. Efforts are also being made to expand the scope of long-term follow-up programs to include late pre-term infants. And finally, efforts to educate the lay public about the risks and benefits associated with early elective deliveries are likely to change the occasional cavalier attitude surrounding near-term births. Only through close cooperation between obstetricians and neonatologists, and through ongoing scientific inquiry to address unanswered questions, will we achieve the best possible outcomes in this large cohort of vulnerable patients.

This work was supported by National Institutes of Health Grant R01HL-063306 to L Jain.

Commentary References

1.	Tita AT, Landon MB, Spong CY, et al; Eunice Kennedy Shriver NICHD Maternal-Fetal Medicine Units Network. Timing of elective repeat cesarean delivery at term and neonatal outcomes. N Engl J Med. 2009;360(2):111-120.

2.	Jain L, Eaton DC. Physiology of fetal lung fluid clearance and the effect of labor. Semin Perinatol. 2006;30(1):34-43.

3.	Jain L, Dudell GG. Respiratory transition in infants delivered by cesarean section. Semin Perinatol. 2006;30(5):296-304.

4.	Davidoff MJ, Dias T, Damus K, et al. Changes in the gestational age distribution among U.S. singleton births: impact on rates of late preterm birth, 1992 to 2002. Semin Perinatol. 2006;30(1):8-15.

5.	Bettegowda VR, Dias T, Davidoff MJ, Damus K, Callaghan WM, Petrini JR. The relationship between cesarean delivery and gestational age among US singleton births. Clin Perinatol. 2008;35(2):309-323,v-vi.

6.	Ananth CV, Gyamfi C, Jain L. Characterizing risk profiles of infants who are delivered at late preterm gestations: does it matter? Am J Obstet Gynecol. 2008;199(4):329-331.

7.	Raju TN, Higgins RD, Stark AR, Leveno KJ. Optimizing care and outcome for late-preterm (near-term) infants: a summary of the workshop sponsored by the National Institute of Child Health and Human Development. Pediatrics. 2006;118(3):1207-1214.

8.	Engle WA. A recommendation for the definition of "late preterm" (near-term) and the birth weight–gestational age classification system. Semin Perinatol. 2006;30(1):2-7.

9.	Wang ML, Dorer DJ, Fleming MP, Catlin EA. Clinical outcomes of near-term infants. Pediatrics. 2004;114(2):372-376.

10.	Jain L. School outcome in late preterm infants: a cause for concern. J Pediatr. 2008;153(1):5-6.

EPIDEMIOLOGY AND ETIOLOGY OF LATE PRE-TERM BIRTH

Bettegowda VR, Dias T, Davidoff MJ, Damus K, Callaghan WM, Petrini JR. The relationship between cesarean delivery and gestational age among US singleton births. Clin Perinatol. 2008;35(2):309-323,v-vi.

(For non-journal subscribers, an additional fee may apply for full text articles.)


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In 2008, Bettegowda and colleagues examined the rise in pre-term deliveries in the United States over the last 25 years, as well as the contribution of cesarean delivery to this increase. The pre-term birth rate reached an all-time high of 12.7% in 2005, up from 9.4% in 1981 — an increase of almost one-third. The authors analyzed US birth records between 1996 and 2004, looking specifically at the impact of cesarean delivery on this change.

The increase in pre-term deliveries has been driven almost exclusively by an increase in the number of infants born between 34 and 36 weeks’ gestation, while the number of extremely pre-term infants has remained relatively constant.^1,2 Many of these deliveries are iatrogenic — either inductions or cesarean sections — and are often referred to as “medically indicated” pre-term births. However, the increase in iatrogenic pre-term deliveries has not been accompanied by a clear rise in maternal or infant risk factors, although some authors cite a greater-than-expected decline in the rate of stillbirths.^3,4

The authors analyzed the 46% increase in cesarean sections (20.7% of births in 1996 vs 30.3% in 2005), which has paralleled a continued rise in pre-term deliveries. Although an increase in cesarean deliveries occurred across all gestational ages, it was most pronounced for pre-term infants. There were 59,057 additional premature births in the United States in 2004, with 54,405 of these by cesarean section. The investigators were not able to differentiate between elective surgery and surgery following a failed induction. Nevertheless, it is clear that cesarean sections are responsible for the substantial majority of the increase.

Recorded rates of both premature deliveries and cesarean sections varied by ethnic group, with African-American infants having the highest rate of prematurity (18.7% in 2005) and non-Hispanic whites the lowest (11.7%). However, according to the authors of this analysis, the rate of prematurity and the proportion of cesarean deliveries have both increased overall in all ethnic groups since 1996, with no sign of abatement. It remains unknown what proportion of these deliveries genuinely merit the morbidity risks intrinsic to a late pre-term infant.

References

1.	Davidoff MJ, Dias T, Damus K, et al. Changes in the gestational age distribution among U.S. singleton births: impact on rates of late preterm birth, 1992 to 2002. Semin Perinatol. 2006;30(1):8-15.

2.	Tomashek KM, Shapiro-Mendoza CK, Davidoff MJ, Petrini JR. Differences in mortality between late-preterm and term singleton infants in the United States, 1995-2002. J Pediatr. 2007;151(5):450-456,456.e1.

3.	Declercq E, Menacker F, Macdorman M. Maternal risk profiles and the primary cesarean rate in the United States, 1991-2002. Am J Public Health. 2006;96(5):867-872.

4.	Joseph KS, Demissie K, Kramer MS. Obstetric intervention, stillbirth, and preterm birth. Semin Perinatol. 2002;26(4):250-259.

SHORT-TERM MORBIDITIES AND MORTALITY IN LATE PRE-TERM INFANTS

Melamed N, Klinger G, Tenenbaum-Gavish K, et al. Short-term neonatal outcome in low-risk, spontaneous, singleton, late preterm deliveries. Obstet Gynecol. 2009;114(2 pt 1):253-260.

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Melamed and associates studied the rates of short-term morbidities in singletons born after spontaneous onset of labor and uncomplicated pregnancies — a group that arguably constitutes the lowest risk group of all late pre-term infants. The authors conducted a retrospective, case-control study of late pre-term infants (34 0/7 to 36 6/7 weeks’ gestation) and compared them with matched term infants. This single-center study of infants born from 1997 to 2006 included 2478 eligible subjects from a total of 5843 late pre-term births.

Patients with pregnancies complicated by maternal illness, including diabetes and hypertension, fetal growth restriction, oligohydramnios, congenital anomalies, and such delivery complications as chorioamnionitis and abnormal fetal heart tracing, were excluded from the study. Those included in the study had not routinely received prenatal steroids or tocolysis. Rates of morbidities (respiratory, infectious, jaundice) were calculated, as well as a composite neonatal outcome measure (presence of any of the selected morbidities), and a number needed to harm (NNH) was generated.

All of the selected outcome measures, with the exception of low Apgar scores, occurred more often in the late pre-term infants than in the term infants, with a continuous rise in the rate of complications with declining gestational age. The incidence of respiratory sequelae (respiratory distress syndrome and transient tachypnea of the newborn) was 12.8% in the late pre-term group; 2.1% required intubation. Jaundice requiring phototherapy was the most common among the other complications (18%), followed by hypoglycemia (6.8%). The incidence of intraventricular hemorrhage (0.2%) and necrotizing enterocolitis (0.4%) were low, but significantly greater than that in term infants (P=.001).

The likelihood of having at least one of the morbidities (composite neonatal outcome) was 30% for the late pre-term group combined, with a high of 49.7% at 34 weeks, decreasing to 34.9% and 22.7% at 35 and 36 weeks, respectively; the rate in term infants was 4.2%. The NNH was 2.9 for any of the morbidities included. No deaths were reported in any of the pre-term infants.

The authors demonstrated that a lower gestational age (34 vs 36 weeks) and male sex were associated with a higher risk for poor outcome. They also noted that even at 37 weeks, there was a trend toward more problems, with no specific gestational age threshold for morbidity being identified. Even in this lower-risk group of late pre-term neonates, the investigators observed a considerable incidence of morbidities, which correlates with other works performed in the late pre-term population over the last several years.^1-3

References

1.	De Luca R, Boulvain M, Irion O, Berner M, Pfister RE. Incidence of early neonatal mortality and morbidity after late-preterm and term cesarean delivery. Pediatrics. 2009;123(6):e1064-e1071.

2.	Ma W, Huang C, Lou S, et al; the Provincial Collaborative Study Group for Late-Preterm Infants. The clinical outcomes of late preterm infants: a multi-center survey of Zhejiang, China. J Perinat Med. 2009 Jul 10. [Epub ahead of print]

3.	Tomashek KM, Shapiro-Mendoza CK, Davidoff MJ, Petrini JR. Differences in mortality between late-preterm and term singleton infants in the United States, 1995-2002. J Pediatr. 2007;151(5):450-456, 456.e1.

THE IMPACT OF WEIGHT AND GESTATIONAL AGE ON MORTALITY IN LATE PRE-TERM INFANTS

Pulver LS, Guest-Warnick G, Stoddard GJ, Byington CL, Young PC. Weight for gestational age affects the mortality of late preterm infants. Pediatrics. 2009;123(6):e1072-e1077.

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Pulver and coworkers evaluated the impact of birth weight and gestational age on mortality in late pre-term (34 to 36 weeks) and early term (37 to 38 weeks) infants compared with term infants. Records from the Utah Department of Health database were used for births and deaths in the state from 1999 to 2005. Both neonatal (<1 month) and infant (<1 year) mortality was considered. Records on a total of 343,322 infants were included, with 25,973 of them late pre-term infants. The authors constructed a population-specific growth curve, on which the infants were categorized as small, appropriate, or large (SGA/AGA/LGA) for gestational age.

According to the investigators, SGA infants had the highest neonatal mortality rate at all gestational ages, but this was particularly pronounced in the late pre-term population. The mortality rate, across both sexes, was more than 40 times higher among SGA late pre-term infants than among AGA term infants. The results were less striking after infants dying of congenital anomalies were excluded from the analysis, but mortality rates continued to be 16.6% (males) and 14.2% (females) times higher. Early term infants also had higher neonatal mortality rates overall (1.6/1000 at 37 weeks), especially in SGA infants (5.4/1000 at 37 weeks). Rates then decreased, falling to a nadir of 0.5 to 0.6/1000 at 39 to 41 weeks.

Congenital anomalies were by far the most common cause of neonatal death in late pre-term infants (75%), with the consequences of prematurity, asphyxia, and infection accounting for the remainder. Infant mortality also increased in all groups as gestational age decreased, with SGA infants being at highest risk. Early term infants (37 to 38 weeks' gestation) continued to have a significantly higher risk for mortality in the first year of life than did later term infants. The authors concluded that there is a group of late pre-term infants at special risk for mortality who warrant particular attention. They also emphasized that even early term infants, especially those with poor growth, have an increased risk for death.

DOES THE ETIOLOGY OF LATE PRE-TERM DELIVERY IMPACT NEONATAL OUTCOME?

Reddy UM, Ko CW, Raju TN, Willinger M. Delivery indications at late-preterm gestations and infant mortality rates in the United States. Pediatrics. 2009;124(1):234-240.

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Reddy and colleagues also examined mortality rates in late pre-term infants, analyzing death rates by delivery indication as recorded on birth certificates. The National Center for Health Statistics birth/death records of all infants born in the United States in 2001 were used, yielding 292,367 late pre-term infants (34 0/7 to 36 6/7 weeks' gestation). The authors developed a classification scheme of the indications for delivery based on infant and maternal characteristics. The 5 categories used included (1) maternal medical conditions (eg, preeclampsia); (2) obstetric complications (eg, fetal distress, oligohydramnios); (3) fetal congenital anomalies; (4) spontaneous delivery (ie, vaginal delivery without induction); and (5) no recorded indication for delivery. This fifth group, which was the main focus of their work, is subject to misclassification bias, although the majority of infants (97.3%) were specifically noted as having no pregnancy complications.

As expected, the study demonstrated increased neonatal mortality rates in late pre-term infants as a whole. Rates were highest at 34 weeks (7.1/1000 births) and lower at 36 weeks (2.8/1000). Again, a nadir (0.8/1000) was observed at 39 to 41 weeks, with a higher incidence of both neonatal and infant mortality reported even among early term infants (37-38 weeks) compared to those born a week or two later.

Stratification by delivery indication placed the largest majority of infants (49%) in the spontaneously delivery category. The late pre-term infants in this group had the lowest mortality rate at 1.9/1000 live births. Infants with congenital anomalies accounted for just over 1% of the births but 27% of the deaths — a rate of 107.9/1000. Obstetric complications also increased the mortality rate (8.8/1000). The no-recorded-indications group had lower mortality rates than these 2 groups, at 3.3/1000, but their rates were significantly (p < 0.001) higher than those of the spontaneous delivery group.

The authors also studied medical and sociodemographic factors in the no-recorded-indications group. Mothers of infants in this group were more likely to be older, more educated, and live outside the Northeast. Interestingly, there was an inverse relationship between this group and prior pre-term births. The investigators thus raised the concern that social and geographic factors are playing a role in who is selected for iatrogenic pre-term delivery, rather than it being based solely on medical indications. This is particularly disturbing, given the fact that the mortality rates among these infants seem to be higher than those among spontaneously delivered infants.

LATE PRE-TERM INFANTS IN EARLY CHILDHOOD AND AT SCHOOL AGE

Morse SB, Zheng H, Tang Y, Roth J. Early school-age outcomes of late preterm infants. Pediatrics. 2009;123(4):e622-e629.

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Long-term outcomes of late pre-term infants have not been well studied. These children are frequently not referred for developmental follow-up, in part because of the perception that they are healthy and in part because the sheer numbers of patients would overwhelm many neonatal follow-up clinics.

Morse and associates addressed early school-age outcomes (up to 6 years of age) in the population of late pre-term infants (34 0/7 to 36 6/7 weeks) born in Florida from 1996 to 1997. Data were obtained from birth certificates, the early intervention program, and the Department of Education on 161,804 infants, 7152 of whom were late pre-term births. Since the objective of the study was to look specifically at “healthy” late pre-term infants, the authors included only those discharged home <72 hours after delivery, and they did not account for readmission rates in their population.

Seven categories indicative of school difficulty or neurodevelopmental delay were compared between late pre-term and term infants. Outcome measures evaluated were (1) the diagnosis of disability or developmental delay defined as participation in early intervention programs (<36months), participation in programs for children with disabilities at (2) age three and (3) at age five, (4) the designation “not ready to start school” by teacher assessment, (5) participation in special education, (6) suspension, and (7) failure to advance to the next grade. Potential confounders were also examined, with pre-term infants more likely to have adolescent mothers with limited education, and higher rates of complications in pregnancy, labor, and delivery.

The late pre-term and term infants differed significantly in 6 of the 7 categories, with the remaining category trending toward an increase. Specifically, the adjusted risk for developmental delay or disability was 36% higher in the late pre-term group, with the other outcome measures increased between 10% and 19%. Notably, an analysis by week of gestation again showed a gradual decline in the percentage of infants experiencing poor outcomes with each completed week of pregnancy, which continued until 39 weeks.

Other recent works have shown an increased prevalence of behavioral problems in infants born at <37 weeks’ gestation, as well as an increased likelihood for poor reading performance and need for special education in elementary school in infants born at 34 to 36 weeks’ gestation.^1,2 When these studies are evaluated in conjunction with the current investigation by Morse and coworkers, there should be significant concern regarding the long-term outcomes in these “healthy” pre-term infants.

References

1.	Gray RF, Indurkhya A, McCormick MC. Prevalence, stability, and predictors of clinically significant behavior problems in low birth weight children at 3, 5, and 8 years of age. Pediatrics. 2004;114(3):736-743.

2.	Chyi LJ, Lee HC, Hintz SR, Gould JB, Sutcliffe TL. School outcomes of late preterm infants: special needs and challenges for infants born at 32 to 36 weeks gestation. J Pediatr. 2008;153(1):25-31.

FINANCIAL IMPACT OF THE CARE OF LATE PRE-TERM INFANTS IN EARLY CHILDHOOD

Clements KM, Barfield WD, Ayadi MF, Wilber N. Preterm birth–associated cost of early intervention services: an analysis by gestational age. Pediatrics. 2007;119(4):e866-e874.

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In another study of long-term outcomes in late pre-term infants, Clements and colleagues examined the financial expense of providing early intervention services to former pre-term infants in the first 3 years of life who were born in Massachusetts. The authors used the Pregnancy to Early Life Longitudinal data system linked to early intervention claims to compute the population-based use and costs of the services delivered to former pre-term infants born in the state from July 1999 to June 2000. A child was considered as having received early intervention services when ≥1 claim had been recorded in the data set, although a proportion of the infants (22%) received only a screening or intake assessment. In this age-group, children who qualified for services had a >25% developmental delay, an established medical condition such as cerebral palsy, or ≥4 risk factors for developmental delay.

A total of 14,033 children across all gestational ages received services — accounting for 18.2% of the 76,901 surviving infants during that year — for a total cost of $66 million. Premature infants, very and moderately pre-term, accounted for 9.9% of deliveries but 24% of the program costs.

The investigators categorized their moderately pre-term group as those infants born at 32 to 36 weeks’ gestation, and found increases in their use of services compared with term infants (32.3% vs 16.0%, respectively), as well as the mean early intervention cost per survivor ($1437 vs $71, respectively). This difference persisted in the older infants in the moderately pre-term group (35 weeks’ gestation, 30.2%; 36 weeks’ gestation, 23.8%). Both the very pre-term and moderately pre-term groups were more likely to qualify for services on the basis of either multiple criteria or severe delay, although this was more pronounced in the most premature infants.

Even at a gestational age of 37 weeks, the receipt of early intervention services (19.4%) was higher than that in infants born at a full 40 weeks’ gestation (14.6%). Overall, the authors found that from the 27th week of pregnancy onward, the necessity for early intervention services decreased continually as gestational age increased.



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