ENHANCEMENT OF OUTCOME FROM INTRACYTOPLASMIC SPERM INJECTION - DOES COCULTURE OR ASSISTED HATCHING IMPROVE IMPLANTATION RATES

In tyro separate prospectively randomized trials, intracytoplasmic spe rm injection (ICSI) cycles were studied in a controlled manner to moni tor the effects of either bovine oviductal epithelial cell co-culture (n = 119) or assisted hatching by zona drilling (n = 100), In the firs t study, immediately following ICSI, all eggs were placed directly eit her onto partial monolayers of bovine oviductal cells or into regular culture medium, Although the embryo developmental rate was apparently compromised in part by the presence of the co-culture cells, ultimatel y there were no significant differences in either the viable pregnancy rate (31.6% co-culture versus 29.0% control) or the embryonic implant ation rate (11.4% co-culture versus 13.6% control). Assisted hatching also had no significant impact on ICSI cycle outcome in terms of eithe r the viable pregnancy rate (30.0% assisted hatching versus 32.0% cont rol) or the embryonic implantation rate (8.5% assisted hatching versus 13.5% control). However, in female patients aged greater than or equa l to 35 years, assisted hatching appeared to convey a marginally signi ficant benefit in terms of both the viable pregnancy rate (35.5% assis ted hatching versus 11.1% control) and the embryonic implantation rate (10.3% assisted hatching versus 3.1% control). It seems that the over all improvement of ICSI cycle outcome cannot be achieved by the genera l application of either co-culture or assisted hatching, Nevertheless, it is possible that there remain specific patient groups that might b enefit from selected use of either of these modalities.