title: First trimester combined screening test in pregnancies derived from blastocyst transfer.
abstract: OBJECTIVE
  To investigate whether first trimester combined screening for major fetal trisomies is influenced by assisted reproduction techniques from blastocyst transfer, with or without cryopreservation.
  
  
  METHODS
  retrospective case-control analysis involving 298 singleton pregnancies with euploid fetuses recruited between 2012 and 2014. Forty-seven women conceived with fresh blastocysts from in vitro fertilization cycles (fresh-blasto), 51 with frozen-thawed blastocysts (frozen-blasto) and 200 were natural conceptions (controls). All cases underwent ultrasound assessment at 11(+0)-13(+6) weeks with measurements of crown rump length, nuchal translucency, free β-hCG and PAPP-A concentrations. The outcome of pregnancy was recorded (gestational age at birth, birth weight, obstetric complications).
  
  
  RESULTS
  Baseline characteristics and pregnancy outcomes did not differ substantially among the study groups. The median delta nuchal translucency was significantly higher both in frozen-blasto group (median: 0.27mm; Interquartile Range [IQR]: 0.02-0.44; p<0.001) and in fresh-blasto group (median: 0.17mm; IQR: 0.04-0.39; p=0.014) as compared to control group (median: 0.06mm; IQR: -0.08 to 0.20), whereas it was not different in the frozen-blasto compared to the fresh-blasto group. The median free β-hCG multiples of the median (MoMs) was significantly higher both in frozen-blasto group (median 1.15; IQR 0.83-2.11; p=0.001) and in fresh-blasto group (median 0.95; IQR 0.52-1.48; p=0.001) as compared to control group (median 0.99; IQR 0.57-1.26), and it was also higher in frozen-blasto group compared to fresh-blasto group (p<0.001). The three groups showed no significant differences in the median PAPP-A MoMs. The median delta crown rump length was also not significantly different among the three groups.
  
  
  CONCLUSIONS
  in assisted reproduction technique pregnancies from blastocyst transfer, with or without cryopreservation, both the nuchal translucency measurement and free β-hCG concentration are higher as compared to spontaneous conceptions, whereas PAPP-A does not show any significant difference. These features are apparently unrelated to the outcome of pregnancy and may be due to alterations or delays in embryogenesis or placentation with potential relevance for the screening test performance.
authors.affiliation: Department of Obstetrics and Gynaecology, IRCCS San Raffaele Hospital, Vita-Salute University, 20132 Milan, Italy. Electronic address: cavoretto.paolo@hsr.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Cavoretto
authors.affiliation: Department of Obstetrics and Gynaecology, IRCCS San Raffaele Hospital, Vita-Salute University, 20132 Milan, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Dallagiovanna
authors.affiliation: Department of Obstetrics and Gynaecology, IRCCS San Raffaele Hospital, Vita-Salute University, 20132 Milan, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Viganò
authors.affiliation: Department of Obstetrics and Gynaecology, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy.
authors.forename: Edgardo
authors.initials: E
authors.lastname: Somigliana
authors.affiliation: Department of Obstetrics and Gynaecology, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Persico
authors.affiliation: Department of Obstetrics and Gynaecology, IRCCS San Raffaele Hospital, Vita-Salute University, 20132 Milan, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Papaleo
authors.affiliation: Department of Obstetrics and Gynaecology, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Faulisi
authors.affiliation: Department of Obstetrics and Gynaecology, IRCCS San Raffaele Hospital, Vita-Salute University, 20132 Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Candiani
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004624:Embryo Transfer; D005260:Female; D006801:Humans; D048208:Nuchal Translucency Measurement; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis; D011296:Prenatal Diagnosis / Q000379:methods; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal
chemical_list: D011266:Pregnancy-Associated Plasma Protein-A
keywords: Assisted reproduction technique; Blastocyst; First trimester; Free beta-hCG; Nuchal translucency; PAPP-A