Fertilization and early embryology: Granulosa cell co-culture enhances human embryo development and pregnancy rate following in-vitro fertilization

A preliminary study and related clinical trial were performed to evaluate the effects of granulosa-lutein cell co-culture on human embryo development and pregnancy rates for in-vitro fertilization (IVF). In the study, sibling two-pronuclear zygotes were randomly allocated to culture with (co-culture) or without (control) autologous granulosalutein cells. After 24 h, embryos were examined for blastomere number and degree of fragmentation. Co-culture had no effect on the average number of blastomeres per embryo at 24 h; however, fragmentation was significantly decreased in co-cultured embryos (0.7 ± 0.1) compared with controls (1.3 ± 0.2; P < 0.05). In the subsequent clinical trial, all two-pronuclear zygotes were co-cultured for 48 h prior to embryo transfer. The live birth rate per embryo transfer was 43.4% with an implantation rate per embryo of 17.6%. Of the untransferred embryos, 68% developed to the blastocyst stage and were cryopreserved. We conclude that the simple system of autologous granulosa-lutein cell co-culture improves embryo development, implantation and subsequent pregnancy rates for IVF.