title: Conjoined twins in a trichorionic quadruplet pregnancy after intracytoplasmic sperm injection and quarter laser-assisted zona thinning.
abstract: OBJECTIVE
  To describe the occurrence and management of conjoined twins (CTs) in a trichorionic quadruplet pregnancy after the transfer of three embryos obtained by intracytoplasmic sperm injection (ICSI) that had undergone assisted zona hatching (AZH) using a noncontact laser.
  
  
  METHODS
  Case report.
  
  
  METHODS
  Private and public IVF centers.
  
  
  METHODS
  A 38-year-old nulliparous woman.
  
  
  METHODS
  IVF, diagnosis by two-dimensional, three-dimensional, and four-dimensional ultrasound, selective termination at 12 weeks gestation.
  
  
  METHODS
  Clinical follow-up and delivery.
  
  
  RESULTS
  After diagnosis, counselling, and selective termination, the subsequent prenatal course was uneventful, and two healthy boys were delivered by elective cesarean section at 38 weeks gestation.
  
  
  CONCLUSIONS
  Monozygotic twinning (MZT) and CTs could complicate multifetal pregnancies obtained by assisted reproduction techniques. The relationship between CTs, IVF, and AZH should be better studied to fully understand the mechanisms that lead to MZT (with the possible role of AZH) and CTs in MZT, in particular. Three-dimensional and four-dimensional ultrasound improve prenatal assessment of the condition. Selective embryo reduction is a safe procedure for the management of these pregnancies.
authors.affiliation: ANDROS Day Surgery, Unità di Medicina della Riproduzione ed Unità di Medicina Fetale, Palermo, Italy. allegra@centroandros.it <allegra@centroandros.it>
authors.forename: Adolfo
authors.initials: A
authors.lastname: Allegra
authors.forename: Giovanni
authors.initials: G
authors.lastname: Monni
authors.forename: Maria Angelica
authors.initials: MA
authors.lastname: Zoppi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Curcio
authors.forename: Angelo
authors.initials: A
authors.lastname: Marino
authors.forename: Aldo
authors.initials: A
authors.lastname: Volpes
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000601:surgery* / Q000628:therapy*; D053685:Laser Therapy; D011247:Pregnancy; D011272:Pregnancy, Multiple; D020554:Sperm Injections, Intracytoplasmic; D016896:Treatment Outcome; D014428:Twins, Conjoined / Q000601:surgery*; D015044:Zona Pellucida