title: Does blastomere biopsy in preimplantation genetic diagnosis affect early serum β-hCG levels?
abstract: OBJECTIVE
  To determine whether the serum β-human chorionic gonadotropin (hCG) profile following preimplantation genetic diagnosis (PGD) is lower than that of intracytoplasmic sperm injection (ICSI) cycles.
  
  
  METHODS
  A total of 129 PGD cycles and 1,161 age-matched ICSI cycles, which resulted in pregnancy (serum β-hCG≥5 mIU/mL) on post-ovulation day (POD) 12 were included. We compared the mean serum β-hCG levels on POD 12, 14, 21, and 28, doubling time of serum hCG, and created a cut-off value for predicting a singleton pregnancy in each group.
  
  
  RESULTS
  The mean serum β-hCG concentration of the PGD group was significantly lower than that of the control group on POD 12, 14, and 21. The doubling time of serum β-hCG at each time interval showed no significant difference. The cut-off-value of serum β-hCG for predicting a single viable pregnancy was 32.5 mIU/mL on POD 12 and 113.5 mIU/mL on POD 14 for the PGD group, which was lower than that for the control group.
  
  
  CONCLUSIONS
  Blastomere biopsy may decrease the β-hCG-producing activity of the trophoblasts, especially in early pregnancy. Setting a lower cut-off value of serum β-hCG for predicting pregnancy outcomes in PGD may be needed.
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital & Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Yeon Jean
authors.initials: YJ
authors.lastname: Cho
authors.forename: Jin Yeong
authors.initials: JY
authors.lastname: Kim
authors.forename: In Ok
authors.initials: IO
authors.lastname: Song
authors.forename: Hyung Song
authors.initials: HS
authors.lastname: Lee
authors.forename: Chun Kyu
authors.initials: CK
authors.lastname: Lim
authors.forename: Mi Kyoung
authors.initials: MK
authors.lastname: Koong
authors.forename: Inn Soo
authors.initials: IS
authors.lastname: Kang