Neonatal mortality for primary cesarean and vaginal births to low-risk women: Application of an "intention-to-treat" model

Marian F. MacDorman, Eugene Declercq, Fay Menacker, Michael Malloy

Research output: Contribution to journalArticle

83 Citations (Scopus)

Abstract

Background: The percentage of United States births delivered by cesarean section continues to increase, even for women considered to be at low risk for the procedure. The purpose of this study was to use an "intention-to- treat" methodology, as recommended by a National Institutes of Health conference, to examine neonatal mortality risk by method of delivery for low-risk women. Methods: Low-risk births were singleton, term (37-41 weeks' gestation), vertex births, with no reported medical risk factors or placenta previa and with no prior cesarean section. All U.S. live births and infant deaths for the 1999 to 2002 birth cohorts (8,026,415 births and 17,412 infant deaths) were examined. Using the intention-to-treat methodology, a "planned vaginal delivery" category was formed by combining vaginal births and cesareans with labor complications or procedures since the original intention in both cases was presumably a vaginal delivery. This group was compared with cesareans with no labor complications or procedures, which is the closest approximation to a "planned cesarean delivery" category possible, given data limitations. Multivariable logistic regression was used to model neonatal mortality as a function of delivery method, adjusting for sociodemographic and medical risk factors. Results: The unadjusted neonatal mortality rate for cesarean deliveries with no labor complications or procedures was 2.4 times that for planned vaginal deliveries. In the most conservative model, the adjusted odds ratio for neonatal mortality was 1.69 (95% CI 1.35-2.11) for cesareans with no labor complications or procedures, compared with planned vaginal deliveries. Conclusions: The finding that cesarean deliveries with no labor complications or procedures remained at a 69 percent higher risk of neonatal mortality than planned vaginal deliveries is important, given the rapid increase in the number of primary cesarean deliveries without a reported medical indication.

Original languageEnglish (US)
Pages (from-to)3-8
Number of pages6
JournalBirth
Volume35
Issue number1
DOIs
StatePublished - Mar 2008

Fingerprint

Infant Mortality
Obstetric Labor Complications
Parturition
Cesarean Section
Placenta Previa
National Institutes of Health (U.S.)
Live Birth
Logistic Models
Odds Ratio
Pregnancy
Mortality

Keywords

  • Birth certificate
  • Cesarean delivery
  • Low-risk women
  • Neonatal mortality
  • Vaginal delivery

ASJC Scopus subject areas

  • Obstetrics and Gynecology
  • Nursing(all)

Cite this

Neonatal mortality for primary cesarean and vaginal births to low-risk women : Application of an "intention-to-treat" model. / MacDorman, Marian F.; Declercq, Eugene; Menacker, Fay; Malloy, Michael.

In: Birth, Vol. 35, No. 1, 03.2008, p. 3-8.

Research output: Contribution to journalArticle

MacDorman, Marian F. ; Declercq, Eugene ; Menacker, Fay ; Malloy, Michael. / Neonatal mortality for primary cesarean and vaginal births to low-risk women : Application of an "intention-to-treat" model. In: Birth. 2008 ; Vol. 35, No. 1. pp. 3-8.
@article{b70833d121624b96bfa9fab772dd8922,
title = "Neonatal mortality for primary cesarean and vaginal births to low-risk women: Application of an {"}intention-to-treat{"} model",
abstract = "Background: The percentage of United States births delivered by cesarean section continues to increase, even for women considered to be at low risk for the procedure. The purpose of this study was to use an {"}intention-to- treat{"} methodology, as recommended by a National Institutes of Health conference, to examine neonatal mortality risk by method of delivery for low-risk women. Methods: Low-risk births were singleton, term (37-41 weeks' gestation), vertex births, with no reported medical risk factors or placenta previa and with no prior cesarean section. All U.S. live births and infant deaths for the 1999 to 2002 birth cohorts (8,026,415 births and 17,412 infant deaths) were examined. Using the intention-to-treat methodology, a {"}planned vaginal delivery{"} category was formed by combining vaginal births and cesareans with labor complications or procedures since the original intention in both cases was presumably a vaginal delivery. This group was compared with cesareans with no labor complications or procedures, which is the closest approximation to a {"}planned cesarean delivery{"} category possible, given data limitations. Multivariable logistic regression was used to model neonatal mortality as a function of delivery method, adjusting for sociodemographic and medical risk factors. Results: The unadjusted neonatal mortality rate for cesarean deliveries with no labor complications or procedures was 2.4 times that for planned vaginal deliveries. In the most conservative model, the adjusted odds ratio for neonatal mortality was 1.69 (95{\%} CI 1.35-2.11) for cesareans with no labor complications or procedures, compared with planned vaginal deliveries. Conclusions: The finding that cesarean deliveries with no labor complications or procedures remained at a 69 percent higher risk of neonatal mortality than planned vaginal deliveries is important, given the rapid increase in the number of primary cesarean deliveries without a reported medical indication.",
keywords = "Birth certificate, Cesarean delivery, Low-risk women, Neonatal mortality, Vaginal delivery",
author = "MacDorman, {Marian F.} and Eugene Declercq and Fay Menacker and Michael Malloy",
year = "2008",
month = "3",
doi = "10.1111/j.1523-536X.2007.00205.x",
language = "English (US)",
volume = "35",
pages = "3--8",
journal = "Birth",
issn = "0730-7659",
publisher = "Wiley-Blackwell",
number = "1",

}

TY - JOUR

T1 - Neonatal mortality for primary cesarean and vaginal births to low-risk women

T2 - Application of an "intention-to-treat" model

AU - MacDorman, Marian F.

AU - Declercq, Eugene

AU - Menacker, Fay

AU - Malloy, Michael

PY - 2008/3

Y1 - 2008/3

N2 - Background: The percentage of United States births delivered by cesarean section continues to increase, even for women considered to be at low risk for the procedure. The purpose of this study was to use an "intention-to- treat" methodology, as recommended by a National Institutes of Health conference, to examine neonatal mortality risk by method of delivery for low-risk women. Methods: Low-risk births were singleton, term (37-41 weeks' gestation), vertex births, with no reported medical risk factors or placenta previa and with no prior cesarean section. All U.S. live births and infant deaths for the 1999 to 2002 birth cohorts (8,026,415 births and 17,412 infant deaths) were examined. Using the intention-to-treat methodology, a "planned vaginal delivery" category was formed by combining vaginal births and cesareans with labor complications or procedures since the original intention in both cases was presumably a vaginal delivery. This group was compared with cesareans with no labor complications or procedures, which is the closest approximation to a "planned cesarean delivery" category possible, given data limitations. Multivariable logistic regression was used to model neonatal mortality as a function of delivery method, adjusting for sociodemographic and medical risk factors. Results: The unadjusted neonatal mortality rate for cesarean deliveries with no labor complications or procedures was 2.4 times that for planned vaginal deliveries. In the most conservative model, the adjusted odds ratio for neonatal mortality was 1.69 (95% CI 1.35-2.11) for cesareans with no labor complications or procedures, compared with planned vaginal deliveries. Conclusions: The finding that cesarean deliveries with no labor complications or procedures remained at a 69 percent higher risk of neonatal mortality than planned vaginal deliveries is important, given the rapid increase in the number of primary cesarean deliveries without a reported medical indication.

AB - Background: The percentage of United States births delivered by cesarean section continues to increase, even for women considered to be at low risk for the procedure. The purpose of this study was to use an "intention-to- treat" methodology, as recommended by a National Institutes of Health conference, to examine neonatal mortality risk by method of delivery for low-risk women. Methods: Low-risk births were singleton, term (37-41 weeks' gestation), vertex births, with no reported medical risk factors or placenta previa and with no prior cesarean section. All U.S. live births and infant deaths for the 1999 to 2002 birth cohorts (8,026,415 births and 17,412 infant deaths) were examined. Using the intention-to-treat methodology, a "planned vaginal delivery" category was formed by combining vaginal births and cesareans with labor complications or procedures since the original intention in both cases was presumably a vaginal delivery. This group was compared with cesareans with no labor complications or procedures, which is the closest approximation to a "planned cesarean delivery" category possible, given data limitations. Multivariable logistic regression was used to model neonatal mortality as a function of delivery method, adjusting for sociodemographic and medical risk factors. Results: The unadjusted neonatal mortality rate for cesarean deliveries with no labor complications or procedures was 2.4 times that for planned vaginal deliveries. In the most conservative model, the adjusted odds ratio for neonatal mortality was 1.69 (95% CI 1.35-2.11) for cesareans with no labor complications or procedures, compared with planned vaginal deliveries. Conclusions: The finding that cesarean deliveries with no labor complications or procedures remained at a 69 percent higher risk of neonatal mortality than planned vaginal deliveries is important, given the rapid increase in the number of primary cesarean deliveries without a reported medical indication.

KW - Birth certificate

KW - Cesarean delivery

KW - Low-risk women

KW - Neonatal mortality

KW - Vaginal delivery

UR - http://www.scopus.com/inward/record.url?scp=40149089112&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=40149089112&partnerID=8YFLogxK

U2 - 10.1111/j.1523-536X.2007.00205.x

DO - 10.1111/j.1523-536X.2007.00205.x

M3 - Article

C2 - 18307481

AN - SCOPUS:40149089112

VL - 35

SP - 3

EP - 8

JO - Birth

JF - Birth

SN - 0730-7659

IS - 1

ER -