title: Delivery modes and pregnancy outcomes of low birth weight infants in China.
abstract: OBJECTIVE
  To investigate and analyze the perinatal outcomes of low birth weight (LBW) infants, thereby selecting the appropriate mode and suitable time of delivery to improve the adverse pregnancy outcomes.
  
  
  METHODS
  A retrospective analysis of 112,441 deliveries (from 39 hospitals of different levels in 14 provinces and autonomous regions in China throughout 2011) were performed in this study to further evaluate the modes of delivery and pregnancy outcomes of LBW infants.
  
  
  RESULTS
  The rate of cesarean section, stillbirth, neonatal asphyxia and mortality of LBW were significantly higher than those of normal birth weight (NBW) infants (odds ratio, 1.24, 56.56, 57.27 and 10.40 times higher, respectively). Stratified analysis showed that adverse events were reduced with the increase in gestational weeks, especially at 34 to 36(+6) weeks. However, LBW infants still had higher risks of adverse events as compared with NBW infants. In particular, full-term LBW babies had a 23.81- and 26.06-fold higher risk of stillbirth and neonatal death as compared with term babies with NBW. In addition, the cesarean delivery rate was 1.24-fold higher for LBW babies than for NBW babies. With an increase in gestational age in LBW infants, the rate of cesarean section was also increased. The rates of stillbirth and neonatal mortality of full-term LBW infants who were delivered via cesarean section (0.5% and 1.0%, respectively) were significantly lower than in the vaginal-delivery group (5.2% and 6.9%, respectively).
  
  
  CONCLUSIONS
  LBW is one of the causes of perinatal death and other adverse pregnancy outcomes and increases the rate of cesarean section. Individualized analysis according to gestational age and intrauterine fetal condition should be performed to extend the gestational age to at least 34 weeks before delivery, cesarean section is a relatively safe mode of delivery, but cannot completely eliminate complications. The key to improving mother and child outcomes is to strengthen pregnancy care and reduce low birth weight infants and premature birth. LBW is one of the causes of adverse pregnancy outcomes in both premature and full-term infants and increases the rate of cesarean section. Individualized analysis of the mode of delivery should be performed to extend the gestational age to 34 weeks and so improve the survival rate.
authors.affiliation: Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Public Health, Beijing Key Laboratory of Epidemiology, Capital Medical University, Beijing, China.
authors.forename: L
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: L
authors.initials: L
authors.lastname: Zou
authors.affiliation: Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: G
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: L
authors.initials: L
authors.lastname: Fan
mesh_terms: D000328:Adult; D001238:Asphyxia Neonatorum / Q000401:mortality*; D001724:Birth Weight; D002585:Cesarean Section / Q000009:adverse effects / Q000401:mortality*; D002681:China / Q000453:epidemiology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D016015:Logistic Models; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D011295:Prenatal Care; D012189:Retrospective Studies; D050497:Stillbirth / Q000453:epidemiology*