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Published on: March 2, 2017
Prediction of pregnancy rate by blastocyst morphological score and age, based on 1,488 single frozen-thawed
Sakae Goto1, Takashi Kadowaki, Satomi Tanaka
1Hanabusa Women's Clinic, Kobe, Japan. gotoms@tcn.zaq.ne.jp
Objective:
To present an estimation of the pregnancy rate after IVF or intracytoplasmic sperm injection stratified by blastocyst morphology and age.
Design:
Retrospective analysis.
Setting:
Private IVF clinic.
Patient(S):
A total of 1,488 single frozen-thawed blastocyst transfer cycles.
Intervention(S):
All frozen-thawed blastocysts used in the study were obtained in the patients' first oocytes retrieval cycles.
Main Outcome Measure(S):
Clinical pregnancy rate (CPR), viable pregnancy rate (VPR), and delivery rate (DR) 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.
Result(S):
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, CPR, 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.
Conclusion(S):
There was a significant correlation between blastocyst quality and CPR, VPR, and DR in addition to the influence of age on the three rates. The findings may help predict successful pregnancy in single-blastocyst transfer.
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