Effect of hyaluronic acid–enriched transfer medium on frozen–thawed embryo transfer outcomes

Abstract Aim To determine if hyaluronic acid–enriched transfer medium (HETM) affects the implantation rate (IR) and clinical pregnancy rate (PR) in women undergoing frozen–thawed embryo transfer (FET). Methods The records of women who underwent FET from May 2014 to October 2014 were retrospectively reviewed. Outcome measures were IR and PR. Results In all 1721 cycles of 1632 patients were included in this study. HETM was used for 347 cycles of 342 patients, and standard medium for 1374 cycles of 1290 patients. Overall, FET outcomes were similar between the groups. For patients undergoing their first FET attempt, the IR (24.3% vs 31.6%, P = 0.042) and clinical PR (34.3% vs 50.1%, P = 0.004) were lower in the HETM group. For patients undergoing their second FET attempt, pregnancy outcomes were similar between the groups. For patients undergoing their third or more FET attempt, HETM was associated with a higher IR (33.3% vs 16.4%, P < 0.001) and higher PR (52.2% vs 27.4%, P < 0.001). Conclusions HETM can improve the embryo IR and clinical PR in patients with repeated implantation failure in the third or more FET attempt. However, the use of HETM for first and second FET should be done with caution.