Is there still a role for a cleavage-stage embryo transfer?

Objective To determine whether pregnancy outcomes are poor or futile when an intended day 5 transfer is converted to a cleavage-stage transfer because of poor embryo development or a lower number of embryos. Design Retrospective cohort study. Setting Academic medical center. Patient(s) Women with a limited number of embryos, defined as ≤6 two pronuclear embryos, after in vitro fertilization. Intervention(s) Patients who had a cleavage-stage transfer were age matched with patients who had a day 5 transfer. Main Outcome Measure(s) Live birth rate. Result(s) A total of 146 women were included in the study with 73 women in each group. Cleavage-stage transfer was associated with significantly lower implantation and clinical pregnancy rates compared with those of day 5 transfer. Although the live birth rate of the cleavage-stage transfer group was lower than that of the day 5 transfer group (25% vs. 40%, respectively), the cleavage-stage transfer still resulted in a live birth rate of 25%. A subanalysis comparing women who did and did not achieve live birth after cleavage-stage transfer demonstrated a live birth rate of 27% when at least one grade A embryo was transferred vs. 17% when a lesser quality embryo (grade B or C) was transferred. Conclusion(s) As expected, the live birth rate after cleavage-stage transfer was lower than that after day 5 transfer. However, the live birth rate of cleavage-stage transfer still fell into acceptable practice, >5%, for patients who were otherwise at very high risk of having no day 5 embryo transfer. Extended culture may not be necessary for all patients.