P18 PGD for a woman carrier of a balanced reciprocal translocation (11;22) and a man with high expression of 16q22 fragile site

Objective: Carriers of chromosomal rearrangements have and increased risk for pregnancy losses and repeated failures in IVF cycles. Couples with balanced translocations are usually good candidates for PGD. We have analyzed the results of the embryology laboratory in our public hospital. Material and Methods: Data were collected from March 2001 until February 2010. A total of 28 IVF-PGD cycles were performed. Reciprocal translocations (RecT) were present in 19 cycles (15 of female carriers and 4 of male carriers) and Robertsonian translocation (RobT) in 9 cycles (4 of female carriers and 5 of male carriers). Female age was 34.9±2.5 (mean±SD). A total of 204 embryos were biopsied on day 3 and analyzed for rearranged chromosomes by FISH. Aneuploidy screening was also performed in selected cases. Normal/ balanced embryos were transferred in day 4 or 5. Data obtained in IVF-PGD cycles were analyzed and compared (RecT vs. RobT; male vs. female carriers). Results: No significant differences were observed in the total number of oocytes retrieved, microinjected oocytes and total obtained embryos regarding the type of translocation (RecT vs. RobT). However, for female carriers we obtained more embryos in cycles of RecT than RobT (8.7±3.8 vs. 6.7±1.2; p = 0.03). The total number of unbalanced embryos was higher for RecT than for RobT (5.4±2.4 vs. 3.0±1.3; p = 0.02). This difference was also observed for female carriers (p = 0.04). Seven out the twentyeight IVF-PGD cycles (1 male-RobT; 1 female-RobT; 1 maleRecT and 4 female-RecT) did not have balanced/normal embryos for transfer. In a female-RecT case, transfer was cancelled because normal/balanced embryos had other chromosomal abnormalities. The mean number of normal/balanced embryos transferred was 1.3±1.0 and no statistical differences were observed regarding the type of translocation, nor the sex carrier. Pregnancy rates were slightly better in RobT cycles than in RecT cycles (33.3% vs. 21.0% per cycle; 42.9% vs. 30.7% per transfer), but differences were not significant. Conclusions: Carriers of reciprocal translocation carriers have less favorable prognosis than those with Robertsonian translocations. We have observed more unbalanced embryos in cycles of reciprocal translocations, mainly in female carriers.