Influence of advanced age on the blastocyst development rate and pregnancy rate in assisted reproductive technology.

OBJECTIVE: To evaluate the percentage of blastocysts developing, the pregnancy rate, the implantation rate, and the abortion rate in women >40 years of age using a cell-free culture system for the development of viable human blastocysts. DESIGN: Retrospective clinical study. SETTING: Private IVF units. PATIENT(S): Two hundred ninety-three cycles in patients undergoing IVF treatment for infertility. Sixty-two cycles were in patients > or =40 years of age, and 231 cycles were in patients <40 years of age. INTERVENTION(S): Pronucleate oocytes obtained from IVF were cultured in vitro for 5-6 days. One to four embryos were transferred. MAIN OUTCOME MEASURE(S): Blastocyst development rate, pregnancy rate, implantation rate, and abortion rate. RESULT(S): From 293 cycles, 3,115 pronucleate oocytes were cultured, producing 1,175 blastocysts. In the women >40 years of age, the blastocyst development rate was 22.2%, and in the younger group, the rate was 40.5%. The pregnancy rate and implantation rate in the > or =40-year age group were 21.1% and 8.9%, respectively; corresponding rates in the younger group were 44.6% and 19.9%. The abortion rate was increased for the > or =40-year age group (25% versus 13.3%). CONCLUSION(S): Success rates for the development of viable human blastocysts, pregnancy, and implantation decline significantly in women > or =40 years old.