Embryonic development and pregnancies following sequential culture in human tubal fluid and a modified simplex...

Pregnancies following human blastocyst transfers were established using a protein supplemented modified potassium simplex optimized medium containing amino acids (KSOM(AA)). Zygotes were first cultured for 2 days in protein supplemented human tubal fluid medium. Resulting embryos (day 3) were subsequently cultured in protein supplemented KSOM(AA) until day 5 of development. Pregnancy and implantation rates were noted after culture and transfer of blastocysts following this culture scheme. The impact of conventional insemination, intracytoplasmic sperm injection (ICSI) and maternal age on developmental rates as well as pregnancy rates was also evaluated. Maternal age had a significant impact (P < 0.05) on developmental rates of embryos until day 3 of culture. Overall, rate of blastocyst development for cultured day 3 embryos was 62%. Patients >39 years of age had lower (P < 0.05) rates of blastocyst development than patients in the younger subgroups. ICSI had no impact on developmental rates until day 3 of culture or rate of blastocyst development. Ongoing pregnancy and implantation rates following culture in KSOM(AA) were 51 and 37% respectively. These results indicate that KSOM(AA) supports high rate blastocyst development and resulting pregnancy rates.