Sequential culture media were introduced in order to meet the changing requirements of the developing embryo in vitro. However, there has been renewed interest in the use of single-step media, which allow the embryo itself to choose the necessary nutrients while maintaining a more stable culture environment. Previous studies suggest that sequential media do not appear superior to single-step media.~The current study will include 2 RCTs:~RCT 1: Random allocation of sibling oocytes to compare embryo development and blastocyst formation rates in the two culture media compared.~RCT2: Random allocation of patients in either Global or Origio media, to evaluate pregnancy rates.
Sequential culture media were introduced in order to meet the changing requirements of the developing embryo in vitro. However, there has been renewed interest in the use of single-step media, which allow the embryo itself to choose the necessary nutrients while maintaining a more stable culture environment. Previous studies suggest that sequential media do not appear superior to single-step media.