THE EFFECTS OF COCULTURE WITH HUMAN FIBROBLASTS ON HUMAN EMBRYO DEVELOPMENT IN-VITRO AND IMPLANTATION

In a human in-vitro fertilization (IVF) programme, the effect of co-cu lture of embryos with human fibroblasts was evaluated with respect to pregnancy rate and embryo development. Patients were included in the s tudy after giving informed written consent. The IVF treatments were ra ndomly assigned by stratification of both age (<36 versus greater than or equal to 36 years) and previous IVF attempts (yes versus no). Afte r fertilization was established, the zygotes were transferred to a 4-w ell dish with or without fibroblasts and cultured for 2 days. On the t hird day after ovum pick-up (OPU), cell number and quality [5 (good) t o 1 (poor)] of the embryos were scored and a maximum of three embryos was transferred, Supernumerary embryos of good quality were cryopreser ved, The design of this study was a group sequential trial with the ob jective of detecting differences between pregnancy rates following IVF with conventional incubation or incubation in co-culture with fibrobl asts, This design included one evaluation at half-way data collection. In the study, 148 patients had an OPU, of,whom 77 were allocated to t he co-culture group, There was no statistically significant difference in pregnancy rate, cell number and embryo quality between the two gro ups. The ongoing pregnancy rate per embryo transfer was 27% in co-cult ure and 30% in the conventional culture group. The implantation rates per transferred embryo were 17 and 18% respectively. Using a multivari ate logistic regression model for the probability of ongoing pregnanci es, the odds ratio of co-culture, adjusted for age and previous IVF at tempts, was not statistically significant. In conclusion, co-culture w ith human fibroblasts does not contribute to an improvement of embryo quality nor to a higher pregnancy rate after IVF in an unselected grou p of patients.