Effect of three pro-nuclei (3PN) on the outcomes of PGT

Abstract

Abstract Aims To explore the influence of 3PN on outcomes in preimplantation genetic testing (PGT) cycles. Methods This was a retrospective study of patients undergoing PGT treatment included 139 PGT for aneuploidy (PGT-A) cycles and 285 cycles PGT for monogenic/single gene defects and/or chromosomal structural rearrangements (PGT-M/SR). The 424 PGT cycles were divided into two groups as follows: group 1 included 343 cycles with no 3PN zygotes and group 2 included 81 cycles with 3PN zygotes. 3PN cycle rate was compared between PGT-A and PGT-M/SR cycles. The outcomes of PGT were analyzed between the two groups. Results The female and male's age were significantly higher in PGT-A than PGT-M/SR cycles. Whereas 3PN rate was not significantly different between the two groups. The number of retrieved oocytes was significantly higher in 3PN group than Non 3PN group (13.98 ± 7.10 vs. 10.89 ± 6.65; P < 0.05). The MII oocyte rate, 2PN fertilizaion rate, D3 high embryo rate, biopsy blastocyst rate, per oocyte utilization and D5 blastocyst rate were significantly lower in 3PN group than Non 3PN group (P < 0.05). The results of chromosomal mosaic rate was significantly higher in 3PN group than Non 3PN group (16.3 vs. 11.9; P < 0.05). Conclusions No correlation was observed between 3PN formation rate and PGT-A or PGT-M/SR cycles. The occurrence of 3PN seems to impair the developing blastocyst and interfere with good embryo formation rate and mosaic rate in PGT. But the occurrence of 3PN does not seem to impair the euploid rate and aneuploid rate.