LATE PRETERM BIRTHS: Why Healthy Babies are Worth the Wait

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LATE PRETERM BIRTHS Why Healthy Babies are
Worth the Wait

• Ruth Ann Shepherd, MD, FAAP, CPHQ
• Director, Division of Adult Child Health
  Improvement,
• Kentucky Department for Public Health

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Objectives

• Define late preterm birth
• Provide rates and trends for late preterm birth
  in the U.S. and selected states
• Discuss the impact of late preterm births on the
  national increase in preterm births
• Review risk factors associated with increasing
  rates of late preterm birth
• Describe the significance of late preterm birth
  respiratory morbidity, abnormal transition,
  hypoglycemia, and brain development

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Late Preterm Births

• Term
• about 40 weeks
• Preterm birth
• lt37 completed weeks
• Late preterm (near-term)
• 34 -36 weeks
• Very preterm
• lt32 weeks

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Preterm Births, Low Birthweight and Infant
MortalityUnited States, 1981 - 2004
Percent
Rate per 1,000 live births
Source National Center for Health Statistics,
final natality and mortality data Prepared by
March of Dimes Perinatal Data Center, 2007
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Three Leading Causes of Infant Mortality United
States, 1990 and 2004
Rate per 100,000 live births
Source National Center for Health
Statistics preliminary mortality data for
2004 Prepared by March of Dimes Perinatal Data
Center, 2007
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Gestational Age-Specific DistributionSingleton
Live Births, Spontaneous United States, 1992,
1997, 2002
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Preterm Birth RatesUnited States, 1983, 1993,
2003, 2005
Percent
gt 1 out of 8 births or 520,000 babies born
preterm in 2005
Percent
HP 2010 Objective
30 Increase
gt12 Increase
Preterm is less than 37 completed weeks
gestation. Source National Center for Health
Statistics, final natality data Prepared by March
of Dimes Perinatal Data Center, 2005 preliminary
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Percent of Live Births that were Preterm
Kentucky and U.S.
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestation
Data Source March of Dimes Peristats National
Center for Health Statistics
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Preterm birth
Florida and US, 1995-2005
Preterm is less than 37 completed weeks
gestation. Source National Center for Health
Statistics, final natality data. Retrieved July
13, 2008, from www.marchofdimes.com/peristats.
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Percent of Live Births that were Preterm Among
Southern Contiguous States
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestation
Data Source March of Dimes Peristats National
Center for Health Statistics
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Percent of Live Births that were Preterm Among
Northern Contiguous States 1993, 2000-2005
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestation
Data Source March of Dimes Peristats National
Center for Health Statistics
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Percent of Live Births to Kentucky Residents
that were Preterm by Area Development District
Year 2005
Kentucky 15.0 U.S. 12.7
9.8
12.8
19.0
15.8
13.1
14.9
14.3
15.1
16.7
15.4
17.6
17.0
14.4
14.0
13.7
Preterm birth is defined as any live birth
occurring before37 completed weeks gestation
Note Area Development District is based on the
Mothers county of residence at time of
birthData Source Kentucky Vital Statistics
Files, Live BirthCertificate Files, 2005
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Selected Categories of Risk for Preterm Birth

• History of Preterm Birth
• Medical Complications/Pre-existing conditions
• Unintended pregnancy
• Maternal Race
• Extremes of Maternal Age
• Multiple Gestations
• C-section delivery
• Gestational age 34, 35,36 weeks

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Maternal Risk Factors Associated with Preterm
Birth in Kentucky, 2004
2004 data is preliminary and numbers could
changeNote p-value lt0.05 is significant
diabetes include pre-existing as well as
gestational cases smoker includes those who
smoked three months prior to pregnancy or
anytime during pregnancyStepwise Logistic
Regression Analysis was used to determine
associations Data Source Kentucky Vital
Statistics Files, Live Birth Certificate Files,
2004
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U.S. Differences in Singleton Preterm Birth
Rates by Race/Ethnicity, 1992 and 2002

• Slide courtesy of Dr. Karla Damus

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Rate of Preterm Birth by Maternal Age
Kentucky, 2001-2003
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestation
Data Source March of Dimes Peristats
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Preterm by maternal age
Florida and Kentucky, 2003-2005 Average
Preterm is less than 37 completed weeks
gestation. Source National Center for Health
Statistics, final natality data. Retrieved July
13, 2008, from www.marchofdimes.com/peristats.
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KY Births to Teen Mothers Women lt20 Years of
AgeTerm and Preterm Births
Data Source Kentucky Vital Statistics Files,
Live Birth Certificate files, 1993, 2000-2005
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KY Births to Older Mothers gt40 Years of
AgeTerm and Preterm Births
Data Source Kentucky Vital Statistics Files,
Live Birth Certificate files, 1993, 2000-2005
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Percent of Live Births Resulting from ART
Kentucky
Data Source Kentucky Vital Statistics Files,
Live Birth Certificate files, 2005
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Percent of Kentucky ART Births by Preterm
Status
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestation2004
data is preliminary and numbers could changeData
Source Kentucky Vital Statistics Files, Live
Birth Certificate files, 2004
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Number of Births that Resulted from ART by
Maternal Age Groups
2004 data is preliminary and numbers could
changeData Source Kentucky Vital Statistics
Files, Live Birth Certificate files, 2004
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Singleton KY Live Births that were Preterm
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestationData
Source Kentucky Vital Statistics Files, Live
Birth Certificate files, 1993, 2000-2005
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Kentucky Live Births by Mode of Delivery
Data Source Kentucky Vital Statistics Files,
Live Birth Certificate Files, 1993, 2000-2005
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KY Preterm Births Delivered Vaginally
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestationData
Source Kentucky Vital Statistics Files, Live
Birth Certificate Files, 1993, 2000-2005
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KY Preterm Births by Cesarean Delivery
Preterm birth is defined as any live birth
occurring lt37 completed weeks gestationData
Source Kentucky Vital Statistics Files, Live
Birth Certificate Files, 1993, 2000-2005
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Preterm Births in Kentucky
Late Preterm 73.4
Source Kentucky Vital Statistics Files, Live
Birth Certificate Files, 2005
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Preterm Births by Week of GestationUnited
States, 2004
Late preterm 71
Source National Center for Health Statistics,
2004 final natality data Prepared by March of
Dimes Perinatal Data Center, 2007
6
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Singleton Preterm Birth RatesUS and Kentucky,
1994-2004
Singleton Preterm Births (lt37wk)
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Late preterm births
Florida and US,
1995-2005
Late preterm is between 34 and 36 completed weeks
gestation. Source National Center for Health
Statistics, final natality data. Retrieved July
13, 2008, from www.marchofdimes.com/peristats.
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Rates of Late Preterm Births (34-36 wks)for All
States, 2005
2005 US Late Preterm Birth Rate 9.1
Source March of Dimes Peristats
Source www.marchofdimes.com/peristats
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Is being a few weeks early a problem?

• LATE PRETERM BABIES
• are born 3 to 6 weeks before their due date

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July 2005- Invitational NICHD Workshop on Near
Term/Late Preterm births (34-36 weeks)
Clinics in Perinatology, Dec 2006 Ed Lucky
Jain, Tonse Raju
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The Late Preterm Infant

• Preterm any neonate whose birth occurs thru the
  end of the last day of the 36th week (259th day)
  following the onset of the last menstrual period
• Late Preterm any neonate whose birth occurs
  beginning the first day of the 34th week (239th
  day) through the end of the last day of the 36th
  week (259th day) following the onset of the last
  menstrual period
• Term any neonate whose birth occurs from the
  beginning of the first day (260th day) of the
  38th week through the end of the last day of the
  42nd weeek (294th day)following the onset of the
  last menstrual period
• Post-term any neonate whose birth occurs from
  the beginning of the first day (295th day) of the
  43rd week following the onset of the last
  menstrual period
• Engle WE. Semin Perinatol 302-6, 2006

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The Late Preterm Infant

• These infants used to be referred to as
  near-term however, they are physiologically
  more like preterm than term infants, and have
  similar risks to preterm
• Many late preterm infants are big enough to go
  to the normal newborn nursery they are still
  immature, and if they get sick, it may not be
  recognized until late
• Most babies admitted to the NICU are late preterm
  infants
• Most babies in NICUs who need respiratory
  support (oxygen, ventilators) are late preterm
  infants