P-254: No advantage of using the sequential GIII media versus the single media Global

Abstract

The sequential media system is based on the concept of the different nutritional requirements of the pre-embryo prior to and post its third day of cell culture (Gardner and Lane, 1998, review). This logic has become the mainstream of the ART lab cell culture media system. The Global media is a modification of the KSOM media, which is based on the potassium simplex optimized calculation. Recently, Biggers and Racowsky (2002) reported on a one media culture system (KSOM + amino acids) that gave similar blastocyst formation rate as the sequential media (P1◊CCM). Using mouse embryos, Biggers, et.al., (2005), reported no significant difference of mouse embryo development and delivery rates between the one-step and two-step sequential culture system. This study intends to compare the performance of the sequential GIII media system with one-step Global media in a human ART trial. A ramdomized prospective study. The Global media was purchased from IVFonline.com, Guelph, Ontario, Canada. The GIII was purchased from Vitrolife, Englewood, Colorado, U.S.A.. With the help from Mr. Michael Baird, Vitrolife’s cell culture specialist, we were familiarized with the unique GIII media culture methodology sequence. All steps were followed to the exact standards. A total 60 cycles were randomly assigned, 30 to the GIII culture system, and 30 to the Global culture system. The criteria for inclusion in this prospective random study were patient age less than 40, and no PGD case (no embryo biopsy). The parameters of hCG pregnancy, ongoing pregnancy, and blastocyst formation rate were analyzed by the Chi-Square test. The GIII media culture system had more biochemical pregnancies while the Global media system had more SAB. Since the number is very small, it is impossible to derive any conclusion. The results did not show any significant trend in favor of any of the specified media systems.Tabled 1 In our system, and with our patient population, there was no advantage of the GIII media over the Global media. The results support Bigger’s conclusion that a 2-step sequential culture protocol is sufficient for the pre-implantation pre-embryo development, and that a one, correctly supplemented media, can also do a successful job throughout the entire length of the cell culture. Apparently, the pre-embryos have some flexibility in adjusting to variations of properly supplemented culture media.