title: First-time births among women 30 years and older in the United States: patterns and risk of adverse outcomes.
abstract: OBJECTIVE
  To update the trends in initiation of childbirth by age of the mother, describing the characteristics of women having their first child at age 30 or above, and to determine the risk for adverse pregnancy outcomes for this group of women.
  
  
  METHODS
  This was a cross-sectional study using National Center for Health Statistics linked live birth and infant death cohort files from 1995 to 2000, and Natality file from 1980 to 2002. Analysis was limited to index pregnancies only. Logistic regression analysis was used to determine the risk of poor outcomes.
  
  
  RESULTS
  There is a decreasing trend of first-time births to women 20-29 years old, while births to women 30 and older are showing a continued rise. As compared to 20-29-year-olds, women who start childbearing at age 30 or older are at increased risk of maternal complications in general. However, 30-34-year-olds have a reduced risk for pregnancy-induced hypertension and pre-existing hypertension. Infants born to women aged 30 and above are at increased risk for prematurity and low birth weight in addition to fetal and infant mortality.
  
  
  CONCLUSIONS
  Because of the increasing trend of women starting childbearing in their 30s and the increased risk for poor outcomes in older women, health providers need to pay extra attention to this group of women as they plan and deliver services for them.
authors.affiliation: Department of Maternal and Child Health, School of Public Health, University of Alabama at Birmingham, 1665 University Boulevard, Room 320, Birmingham, AL 35294, USA. nabukera@uab.edu
authors.forename: Sarah
authors.initials: S
authors.lastname: Nabukera
authors.forename: Martha Slay
authors.initials: MS
authors.lastname: Wingate
authors.forename: Greg R
authors.initials: GR
authors.lastname: Alexander
authors.forename: Hamisu M
authors.initials: HM
authors.lastname: Salihu
mesh_terms: D000328:Adult; D001723:Birth Rate / Q000639:trends*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008423:Maternal Age; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D011256:Pregnancy Outcome / Q000453:epidemiology*; D011295:Prenatal Care / Q000706:statistics & numerical data; D012307:Risk Factors; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology