PREIMPLANTATION DIAGNOSIS OF COMMON ANEUPLOIDIES BY THE FIRST-POLAR AND 2ND-POLAR BODY FISH ANALYSIS

Purpose: A low pregnancy rate in in vitro fertilization (IVF) patients of advanced maternal age may be caused by aneuploidies originating fr om non disjunction in the first or second meiotic divisions. We introd uced genetic testing of oocytes by sampling and fluorescent in situ hy bridization (FISH) analysis of the first and second polar bodies, to a void fertilization and transfer of aneuploid oocytes in IVF patients o f advanced maternal age. Methods: Three hundred and sixty-three IVF pa tients 34 years and older participated in the study. Using micromanipu lation procedures, the first and second polar bodies were removed foll owing their extrusion from the oocytes and studied by FISH, using prob es specific for chromosomes 13, 18, and 21 to detect oocytes with comm on aneuploidies. Results: Of a total of 538 IVF cycles, 3250 oocytes w ere available for FISH analysis, with conclusive FISH results in 2742 oocytes (84.3%). As many as 1102 (40%) of oocytes were predicted to be aneuploid and not transfer red. Of 1640 embryos predicted to be norma l, 1145 were transfer red in 467 treatment cycles, resulting in 107 pr egnancies (23%), from which 67 healthy children have been born, 32 pre gnancies spontaneously aborted, and 15 pregnancies are ongoing after b eing confirmed normal by prenatal diagnosis. Conclusions: Preimplantat ion diagnosis by first-and second-polar body FISH analysis allows us t o avoid the age-related risk of common aneuploidies in IVF patients of advanced maternal age.