研究開発・学会発表

OBJECTIVE: To present an estimation of pregnancy and delivery rates after IVF or ICSI stratified by blastocyst morphology and age.

DESIGN: Retrospective analysis.

MATERIALS AND METHODS:A total of 1488 single frozen-thawed blastocyst transfer cycles were included in the study. All frozen-thawed blastocysts used in the study were obtained in the patient’s first oocytes retrieval cycles. Viable pregnancy rate (VPR; number of viable pregnancy cycles / number of transfer cycles) and delivery rate (DR; number of delivery cycles / number of transfer cycles) according to blastocyst morphological score (Gardner and Schoolcraft score) in three different age groups; women aged 22 – 33 years, 34-37 years and 38 – 45 years were analyzed.

RESULTS: The quality of blastocysts degraded as age group increased.  The proportions of good quality blastocysts (Grades 4 and above) were 62.3%, 56.3%, and 41.1% in age groups of 22-33 years, 34-37 years, and 38 – 45 years.  Within the same blastocyst quality, VPR and DR tended to be lower with increased age. Chances of pregnancy were reduced by 60% or more for women 38 years and older with blastocyst morphology of Grades 1 and 2. Significant trends were observed for both age and blastocyst morphology groups.

CONCLUSIONS:  There was a significant correlation between blastocyst quality and both VPR and DR in addition to the influence of age. The findings may help predict successful pregnancy in single blastocyst transfer.