Granulosa cells improve human embryo development in vitro.

A total of 17 couples with repetitive implantation failure after transfer of fresh or frozen-thawed embryos had half of their zygotes cultured in standard conditions and frozen at day 2 after insemination, and the other half cocultured with autologous granulosa cells and transferred at the morula or blastocyst stage at day 5 or 6 after oocyte retrieval. At the end of the culture period, supernatants of cocultures were recovered for steroid assays. Monolayers were stained for granulosa cell growth and morphological assessment. We observed that granulosa cells improve embryo development in vitro since 32 out of 60 (53%) reached the morula stage and 18 (30%) the blastocyst stage, leading to a total of 83% embryos available for transfer (compared with 3% without coculture). The ongoing pregnancy rate of these patients who were selected because they had at least three previous implantation failures, is only 5.9%, however, which is similar to the control group without coculture (6.3%). To conclude, granulosa cells improve embryo development but not the pregnancy rate after transfer of cocultured embryos in patients with multiple previous implantation failures.