Cumulative reproductive outcome after preimplantation genetic diagnosis: a report on 1498 couples

BACKGROUND Couples undergoing preimplantation genetic diagnosis (PGD) have a different background and set of treatment characteristics to couples undergoing regular IVF or ICSI. The aim of this study was to analyse the cumulative reproductive outcome of a large cohort of couples undergoing PGD in relation to a number of explanatory variables potentially affecting the prognosis. METHODS Prospective cohort study, Kaplan-Meier analysis was performed to estimate real (observed) and expected (calculated) cumulative delivery rates, and Cox proportional hazard regression analysis was used to assess the effect of age, number of cumulus oocyte complexes collected, fertility status, parity, genetic category and method of pituitary suppression. RESULTS Between 1993 and 2005, 2753 unselected consecutive cycles of ICSI and PGD were carried out in 1498 couples. The cumulative observed delivery rate overall per couple with a maximum of six treatment cycles of ICSI and PGD performed was 29%. The expected cumulative delivery rate (max six cycles) overall was 62%. There were no significant differences in cumulative delivery rates between the different genetic categories (i.e. availability of transferable embryos after PGD of 50 or 75%, chromosomal translocations or aneuploidy screening). The cumulative reproductive outcome in this PGD cohort was also not significantly affected by the fertility status of the couple, their parity or the method of pituitary suppression. However, the age of the patient and the number of oocytes contributed significantly to the reproductive results. CONCLUSION This prospective observational study demonstrates that age has a significantly negative effect on outcome of PGD, due to poor reproductive performance of female partners 40 years of age and older. The number of oocytes collected has a significant and independent effect. The other factors studied did not affect the cumulative reproductive outcome in this PGD cohort.