Clinical Outcomes of Frozen-thawed Embryo Transfer after Microsurgical Removal of Damaged Blastomere

Choi, Won Yun; Sohn, Jie Ohn; Park, Eun A; Lee, Dong Ryul; Lee, Woo Sik; Han, Se Yul; Park, Lee Suk; Cho, Jung Hyun; Kim, Soo Hee; Cha, Kwang Yul; Yoon, Tae Ki

Abstract

OBJECTIVE
Human infertility clinics have been faced the demand for improving clinical results. The purpose of this study was to evaluate the effect of microsurgical removal of damaged blastomeres (DB) in frozen-thawed embryos on the clinical outcomes.
METHODS
From January 2003 to May 2004, out of 258 thawing ET cycles were divided into three groups: Group-1 (n=46): Intact cleavaged embryos after thawing. Remained cycles with embryos containing DB were randomly divided into two groups. Group-2 (n=102): Drilling zona pellucida (ZP) of frozen-thawed embryos by acidified Tyrode's solution. Group-3 (n=110): Drilling ZP and removal of DB. Embryos after microsurgical manipulation were transferred into the uterus of patients.
RESULTS
Clinical profiles and the mean number of transferred embryos among three groups were not different. Pregnancy and implantation rates were similar in three groups. It were 30.4% and 9.3% in Group-1, 29.4% and 7.8% in Group-2, and 26.4% and 7.6% in group-3, respectively. Miscarriage rate in Group-3 (37.9%) was slightly higher than those in Group-1 and Group-2 (14.3% and 23.3%), but it was not statistically significant.
CONCLUSION
Intact cleaving embryos after DB removal showed higher potent of pregnancy and implantation. We could not find any improvement of clinical outcome by removal of DB in frozen-thawed embryos.