title: Impact of induced pregnancies in the obstetrical outcome of twin pregnancies.
abstract: OBJECTIVE
  To compare obstetric outcomes of induced twins with those spontaneously conceived.
  
  
  METHODS
  A prospective observational study was conducted in twin pregnancies delivered over 16 years.
  
  
  METHODS
  A tertiary obstetric center with differentiated perinatal support.
  
  
  METHODS
  A total of 180 induced twins and 698 spontaneously conceived were included.
  
  
  METHODS
  None.
  
  
  METHODS
  Comparison of demographic factors, obstetrical complications, gestational age at delivery, mode of delivery, birth weight, and immediate newborn outcome.
  
  
  RESULTS
  First-trimester bleeding was higher in the induced group (6.0% vs. 12.2%), as were gestational diabetes (4.4% vs. 8.3%) and discordant intrauterine growth (4.3% vs. 11.1%). Preterm premature rupture of membranes was less frequent (23.9% vs. 12.8%) as was preterm delivery ≤32 weeks (22.5% vs. 14.0%). Cesarean section rate was higher (50.6% vs. 63.9%). Other obstetrical complications, newborn data, and puerperal complications were not statistically different. Except for first-trimester bleeding (significantly associated with monochorionicity), these results were independent from chorionicity. Regarding the induced method (ovulation induction, IVF, or ICSI), IVF is a predictor for first-trimester bleeding and IVF or ICSI a predictor for cesarean section.
  
  
  CONCLUSIONS
  The higher rates found with induced twins of first-trimester bleeding, gestational diabetes, and discordant growth do not contribute to different neonatal immediate outcomes and do not contribute to higher rates of prematurity, low birth weight, or other major perinatal complications.
authors.affiliation: Obstetrics-A Department, Coimbra Hospital and University Center, Coimbra, Portugal. Electronic address: anapatriciadomingues@hotmail.com.
authors.forename: Ana Patrícia
authors.initials: AP
authors.lastname: Domingues
authors.affiliation: Obstetrics-A Department, Coimbra Hospital and University Center, Coimbra, Portugal.
authors.forename: Sofia Raposo
authors.initials: SR
authors.lastname: Dinis
authors.affiliation: Biostatistician, Coimbra, Portugal.
authors.forename: Adriana
authors.initials: A
authors.lastname: Belo
authors.affiliation: Human Reproduction Department, Coimbra Hospital and University Center, Coimbra, Portugal.
authors.forename: Daniela
authors.initials: D
authors.lastname: Couto
authors.affiliation: Obstetrics-A Department, Coimbra Hospital and University Center, Coimbra, Portugal.
authors.forename: Etelvina
authors.initials: E
authors.lastname: Fonseca
authors.affiliation: Obstetrics-A Department, Coimbra Hospital and University Center, Coimbra, Portugal; Obstetrical Clinic, Faculty of Medicine, Coimbra University, Coimbra, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Moura
mesh_terms: D000293:Adolescent; D000328:Adult; D036861:Delivery, Obstetric / Q000639:trends*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D059285:Pregnancy, Twin / Q000502:physiology; D011446:Prospective Studies; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects / Q000639:trends*; D055815:Young Adult
keywords: Twins; induced reproduction; obstetrical outcomes