title: Maternal serum pregnancy-associated plasma protein-A and free beta-human chorionic gonadotrophin in pregnancies conceived with fresh and frozen-thawed embryos from in vitro fertilization and intracytoplasmic sperm injection.
abstract: OBJECTIVE
  Maternal serum pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotrophin (beta-hCG) are useful markers in the screening of Down syndrome in the first trimester. We investigated the effect of intracytoplasmic sperm injection (ICSI), freezing and thawing of embryos on the levels of these two analytes in assisted reproduction pregnancies.
  
  
  METHODS
  We recruited 149 women who conceived after assisted reproduction with fresh embryos (92 from conventional IVF and 57 from ICSI), 85 women who conceived with frozen-thawed embryos (54 from conventional IVF and 31 from ICSI) and 401 women with spontaneous conceptions as controls. The concentrations of PAPP-A and free beta-hCG were measured between 10 and 14 weeks and were converted to multiples of medians (MoM) for comparisons.
  
  
  RESULTS
  Median PAPP-A MoMs were significantly reduced in ICSI pregnancies in the fresh and frozen-thawed embryo subgroups (0.70 and 0.66 MoM respectively) and in the IVF fresh embryo subgroups (0.83 MoM), as compared to controls (1.00 MoM). Free beta-hCG MoM was significantly reduced in the IVF fresh embryos subgroup (0.87 MoM), but not in the other three subgroups.
  
  
  CONCLUSIONS
  Further studies for exploring the underlying pathophysiology and adjustment in the marker levels for screening of Down syndrome are warranted in pregnancies conceived after assisted reproduction.
authors.affiliation: Department of Obstetrics and Gynaecology, Queen Mary Hospital, Hong Kong. pwhui@graduate.hku.hk
authors.forename: Pui Wah
authors.initials: PW
authors.lastname: Hui
authors.forename: Yung Hang
authors.initials: YH
authors.lastname: Lam
authors.forename: Mary Hoi Yin
authors.initials: MH
authors.lastname: Tang
authors.forename: Ernest Hung Yu
authors.initials: EH
authors.lastname: NG
authors.forename: William Shu Biu
authors.initials: WS
authors.lastname: Yeung
authors.forename: Pak Chung
authors.initials: PC
authors.lastname: Ho
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D015925:Cryopreservation; D004314:Down Syndrome / Q000097:blood / Q000175:diagnosis; D004622:Embryo, Mammalian; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008875:Middle Aged; D011237:Predictive Value of Tests; D011247:Pregnancy / Q000097:blood*; D011261:Pregnancy Trimester, First / Q000097:blood; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism*; D011296:Prenatal Diagnosis; D020554:Sperm Injections, Intracytoplasmic
chemical_list: D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D011266:Pregnancy-Associated Plasma Protein-A