Prediction of pregnancy rate by blastocyst morphological score and age, based on 1,488 single frozen-thawed blastocyst transfer cycles

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. (Fertil Steril (R) 2011; 95: 948-52. (C) 2011 by American Society for Reproductive Medicine.)