Does blastomere biopsy in preimplantation genetic diagnosis affect early serum β-hCG levels?

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. CONCLUSION 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.