Does the duration of gonadotropin stımulation affect embryo quality on post-retrieval day 3?

AIM: To determine if the duration of ovarian hyperstimulation affects quality of embryos on the 3rd day. METHODS: Retrospective cohort study was designed in a University affiliated hospital. Six-hundred fifteen women undergoing first IVF treatment were grouped according to the duration of controlled ovarian hyperstimulation (COH) in long-down regulated cycles. Group A consisted of women with 8 or less days of COH, Group B consisted of women who had between 9 and 10 days of COH and Group C had 11 days or more COH. The degree of fragmentation and asymmetry of blastomeres were compared for the 3rd day after oocyte retrieval. RESULTS: On day 3, there were more embryos with 10-25% fragmentation in Group A than in Group B. Embryos were also less symmetrical in Group A than in Group B. CONCLUSIONS: COH cycles which are shorter than 9 days result in more embryos with more than 10% fragmentation on post-retrieval day 3.