Development and integration of an extended embryo culture program.

ABSTRACT

OBJECTIVE: To study and evaluate a sequential, extended embryo culture system. DESIGN: Prospective study. SETTING: University-affiliated IVF clinic. PATIENT(S) All couples who were treated between October 1997 and July 1998. INTERVENTION(S) A standard human tubal fluid plus 10% serum substitute supplement (SSS) culture medium was used. The embryos were transferred to extended culture medium (S2 or G2) on day 3. MAIN OUTCOME MEASURE(S) Blastocyst formation and implantation and pregnancy rates. RESULT(S) Forty percent of the 20 donated cryopreserved embryos progressed to the blastocyst stage by day 6. Clinically, 7 (5.6%) of the 125 cycles did not result in a transfer. Blastocyst formation rates ranged from 33%-63% in the five study groups. Implantation rates ranged from 15%-52% and pregnancy rates ranged from 37%-75%. CONCLUSION(S) Extended culture to day 5 or 6 results in acceptable blastocyst formation rates, implantation rates, and pregnancy rates.