title: Trends in the delivery route of twin pregnancies in the United States, 2006-2013.
abstract: OBJECTIVE
  To determine the trends of cesarean delivery rate among twin pregnancies from 2006 to 2013.
  
  
  METHODS
  This is a population-based, cross-sectional analysis of twin live births from United State birth data files of the National Center for Health Statistics for calendar years 2006 through 2013. We stratified the population based on the gestational age groups, maternal race/ethnicity, advanced maternal age (AMA) which was defined by age more than 35 years and within the standard birth weight groups (group 1: birth weight 500-1499g, group 2: birth weight 1500-2499g and group 3: birth weight >2500g). We also analyzed the effect of different risk factors for cesarean delivery in twins.
  
  
  RESULTS
  There were 1,079,102 infants born of twin gestations in the U.S. from 2006 to 2013, representing a small but significant increase in the proportion of twin births among all births (3.2% in 2006 versus 3.4% in 2013). The rate of cesarean delivery in twin live births peaked at 75.3% in 2009, and was significantly lower (74.8%) in 2013. The rate of the twin live birth with the breech presentation increased steadily from 26.3% in 2006 to 29.1% in 2013. For the fetus of the twin pregnancy presented as breech, the cesarean delivery rate peaked at 92.2% in 2010, falling slightly but significantly in the ensuing 3 years. The results demonstrated that the decrease in cesarean delivery rate was due to fewer cesareans in non-Hispanic white patients; all other ethnic subgroups showed increasing rates of cesarean delivery throughout the study. Gestational diabetes, gestational hypertension, previous cesarean delivery and breech presentation were all significant risk factors for cesarean delivery during the entire study period. Induction of labor and premature rupture of the membranes were associated with lower rates of cesarean delivery in twins.
  
  
  CONCLUSIONS
  The recent decrease in the cesarean delivery rate in twin gestation appears to be largely attributable to a decline in cesarean among pregnancies complicated by breech presentation in non-Hispanic white women, and may reflect a health care disparity that deserves further research.
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Zhoobin H
authors: ZH
authors: Bateni
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Steven L
authors: SL
authors: Clark
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Haleh
authors: H
authors: Sangi-Haghpeykar
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Kjersti M
authors: KM
authors: Aagaard
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Stanford University School of Medicine, Palo Alto, CA, United States.
authors: Yair J
authors: YJ
authors: Blumenfeld
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Susan M
authors: SM
authors: Ramin
authors: Division of Neonatal & Developmental Medicine, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA, United States.
authors: Henry C
authors: HC
authors: Lee
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Karin A
authors: KA
authors: Fox
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Amirhossein
authors: A
authors: Moaddab
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Amir A
authors: AA
authors: Shamshirsaz
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Bahram
authors: B
authors: Salmanian
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Pardis
authors: P
authors: Hosseinzadeh
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Diana A
authors: DA
authors: Racusin
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Hadi
authors: H
authors: Erfani
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Jimmy
authors: J
authors: Espinoza
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Gary A
authors: GA
authors: Dildy
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States.
authors: Michael A
authors: MA
authors: Belfort
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital Pavilion for Women, Houston, TX, United States. Electronic address: alirezashamshirsaz@yahoo.com.
authors: Alireza A
authors: AA
authors: Shamshirsaz
mesh_terms: D000328:Adult; D001946:Breech Presentation; D002585:Cesarean Section / Q000639:trends*; D003430:Cross-Sectional Studies; D036861:Delivery, Obstetric / Q000639:trends*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D011247:Pregnancy; D011256:Pregnancy Outcome; D059285:Pregnancy, Twin; D014481:United States
keywords: Cesarean delivery; Delivery route; Trend; Twin; Twin pregnancy; Vital statistics