A randomized controlled study of human serum albumin and serum substitute supplement as protein supplements for IVF culture and the effect on live birth rates

It has been speculated that the addition of proteins more complex than human serum albumin (HSA) to culture media may improve IVF outcomes. Whether the expense, labor and risk of adding additional human-derived protein to IVF media are warranted is a question unanswered. In a randomized controlled trial with couples undergoing routine IVF or ICSI, 528 patients were assigned to one of two treatment groups. Embryos were cultured in either media supplemented with HSA as a solitary protein supplement or in media supplemented with HSA+serum substitute supplement (SSS) from the 2PN stage until the time of embryo transfer. Clinical end-points monitored included implantation (total 1151 embryos) and live birth rates (total 528 patients). The transfer of embryos cultured in HSA+SSS resulted in higher embryo implantation (289/571, 50.6% versus 254/580, 43.8%; difference 6.8% with 95% CI 1.0–12.7, P = 0.042) and live birth rates (167/266, 62.8% versus 142/262, 54.2%; difference 8.6% with 95% CI 0.1–17.3, P = 0.043) when compared with those of women whose embryos were cultured with HSA as the sole protein supplement. SSS added to commercial HSA-supplemented embryo culture media resulted in an overall increase in implantation and live birth rates. It remains uncertain whether the use of human-derived blood products in culture media and the requirement for ultra-rigorous quality control measures make these findings applicable to the average IVF laboratory. Protein enrichment of media may significantly improve the blastocyst implantation rate, creating opportunities to transfer single blastocysts without compromising the live birth rate.The study was registered at clinicaltrials.gov. NCT00708383.