Comparison between embryos transferred with self-spent and fresh medium on reproductive outcomes: a prospective randomized trial.

UNLABELLED: As the final and critical step in in vitro fertilization (IVF), embryo transfer has always received much attention and deserves continuous optimization. In the present study, to explore the role of autocrine factors in embryo self-spent culture media, we prospectively compared embryo transfer with self-spent culture medium and fresh medium on clinical pregnancy outcomes. A total of 318 fresh IVF/intracytoplasmic sperm injection (ICSI) cycles were randomly allocated into two subgroups based on their transfer media (using a self-spent culture medium or new pre-equilibrated culture media), and the clinical outcomes were compared between groups. The implantation rates, clinical pregnancy rates and live birth rates for transfer using self-spent medium instead of new pre-equilibrated culture medium were slightly improved without statistical significance. Interestingly, however, biochemical pregnancy rate was found to be significantly decreased after transfer using self-spent medium for Day 3 embryos compared with new pre-equilibrated culture media. In short, embryo transfer with self-spent culture medium has shown some advantages, and large sample size studies are still needed to confirm these observations.

ABBREVIATIONS: ART: assisted reproductive technologies; ICSI: intracytoplasmic sperm injection; IVF: in vitro fertilization; ET: embryo transfer.