title: Neonatal outcomes in very preterm singleton infants conceived using assisted reproductive technologies.
abstract: OBJECTIVE
  To compare neonatal mortality, severe morbidities and hospital length of stay in very preterm singleton infants conceived using assisted reproductive technologies (ARTs) or spontaneously (SP).
  
  
  METHODS
  Singleton infants born at 23 to 32 weeks gestation during 2010-2012 were retrospectively identified from the Canadian Neonatal Network database. A composite outcome indicating a mortality or severe morbidity (grade ≥ 3 intraventricular hemorrhage, periventricular leukomalacia, stage ≥ 3 retinopathy of prematurity, bronchopulmonary dysplasia, or stage ≥ 2 necrotizing enterocolitis) was compared between ART and SP infants using multivariable logistic regression. Length of stay was examined in multivariable time-to-event analyses adjusting for competing risk of mortality.
  
  
  RESULTS
  Eligible subjects included 346 (4.4%) ART and 7,578 (95.6%) SP infants. ART mothers were older, with fewer single parents, higher rates of nulliparity, diabetes, hypertension, antenatal corticosteroids, and prenatal care, but less smoking and substance use than SP mothers. No significant differences were detected in the composite outcome (odds ratio: 0.79; 95% confidence interval: 0.54-1.17) or length of stay (hazard ratio: 0.84; 95% confidence interval: 0.63-1.12) between ART and SP infants after adjustment for potential confounders and risk factors.
  
  
  CONCLUSIONS
  Among singleton infants born very preterm, mode of conception is not associated with overall mortality/morbidity or length of stay.
authors.affiliation: Maternal-Infant Care Research Centre, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Laura
authors.initials: L
authors.lastname: Chiarelli
authors.affiliation: Maternal-Infant Care Research Centre, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Lucia
authors.initials: L
authors.lastname: Mirea
authors.affiliation: Maternal-Infant Care Research Centre, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Junmin
authors.initials: J
authors.lastname: Yang
authors.affiliation: Maternal-Infant Care Research Centre, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Shoo K
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Maternal-Infant Care Research Centre, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Prakesh S
authors.initials: PS
authors.lastname: Shah
mesh_terms: D002170:Canada; D002543:Cerebral Hemorrhage; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000401:mortality*; D007902:Length of Stay / Q000706:statistics & numerical data*; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D011247:Pregnancy; D047928:Premature Birth; D011295:Prenatal Care; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index