O-21. Some mosaic types increase with maternal age

The utility of embryo banking in order to increase the number of embryos available for preimplantation genetic screening in advanced maternal age patients

PURPOSE

to determine if embryo banking with PGS is more optimal than proceeding with PGS regardless of embryo number.

METHODS

patients were divided into 2 groups, group 1 were those that banked embryos and proceeded through another round of IVF prior to PGS, and group 2 underwent PGS regardless of embryo number. Group 2 was divided into group 2A (patients with >10 embryos) and group 2B (patients who had <10 embryos).

RESULTS

there was no difference in embryos biopsied, normal embryos, number transferred, and pregnancy rate between group 1 and 2. A significant number of patients did not have a transfer in group 2B (6/11) compared to group 1 (3/19) (P = 0.0419). There was no significance between pregnancy rates per transfer between group 1 (6/16) and group 2B (2/5).

CONCLUSION

our data suggests that banking will increase the odds of going to transfer but there was no increase in pregnancy rates.

Current features of preimplantation genetic diagnosis

More than 4000 preimplantation genetic diagnosis (PGD) cycles have been performed, suggesting that PGD may no longer be considered a research activity. The important present feature of PGD is its expansion to a variety of conditions, which have never been considered as an indication for prenatal diagnosis, including the late-onset disorders with genetic predisposition and preimplantation non-disease testing, with the further improvement of the accuracy of PGD for single gene disorders. PGD has also become a useful tool for the improvement of the effectiveness of IVF, through avoiding the transfer of chromosomally abnormal embryos, representing more than half of the embryos routinely transferred in IVF patients of advanced maternal age and other poor prognosis patients. PGD is of particular hope for the carriers of balanced chromosomal translocations, as it allows accurate pre-selection of a few balanced or normal embryos resulting from the extremely poor meiotic outcome, especially in reciprocal translocations. With the current progress in polymerase chain reaction- (PCR-) based detection of chromosomal abnormalities in oocytes and embryos, PGD may soon be performed for both chromosomal and single gene disorders using the same biopsied polar body or blastomere, frequently required with the currently expanded PGD application. The available clinical outcome data of more than 3000 PGD embryo transfers further suggest an acceptable pregnancy rate and safety of the procedure, as demonstrated by the follow-up information available for more than 500 children born from these PGD transfers.