Thawing cryopreserved oocytes: genetic screening of thawed oocytes and ongoing pregnancy success rate

Abstract

ObjectiveTo compare clinical outcomes after Oocyte thaw (OOT) with and without preimplantation genetic screening (PGS), and to compare those outcomes with those of In Vitro Fertilization (IVF) with PGS.DesignRetrospective cohort study.Materials and Methods270 previously cryopreserved oocytes from 15 patients (27-42 years) were thawed/warmed, fertilized, cultured to blastocyst, and underwent trophectoderm biopsy on days 5 or 6 for analysis of ploidy by array comparative genomic hybridization (a-CGH) prior to transfer (OOT/PGS). 96 blastocysts were analyzed for ploidy. Only normal euploid embryos were transferred of embryos biopsied on days 5 or 6. OOT/PGS cycle outcomes were compared with 646 previously cryopreserved oocytes (OOT/No PGS) from 67 patients as well as 1416 blastocysts analyzed by a-CGH from 233 IVF/PGS cycles. Only patients’ first OOF /thaw (or warming) /PGS or IVF/PGS cycles were included. Donor egg cases were excluded from analysis. Cryopreservation and IVF/PGS cycles occurred between February 2007 and January 2014, thaw or warming cycles between June 2010 and March 2014. Outcomes included implantation rate (IR), clinical pregnancy rate (CPR) and ongoing pregnancy rate (OPR). CPR was defined by ultrasound-visualized sac. Patient cycle parameters were compared. ANOVA and X2 were used for analysis (p<0.05).ResultsTabled 1Clinical outcomes from OOF cycles with and without PGS in comparison to IVF cycles with PGSOOT with PGS (n=15)OOT without PGS (n=67)IVF with PGS (n=233)p-valueImplantation Rate50%25%66%0.0004*Clinical pregnancy rate53%45%69%0.0016*Live birth and ongoing pregnancy rate60%43%64%0.0047* Open table in a new tab ConclusionPGS in conjunction with OOT yields IR, CPR and OPR comparable to those observed for IVF/PGS. Due to the preliminary nature of this work, we expect ongoing data will reinforce conclusive significance for OOT/PGS application. ObjectiveTo compare clinical outcomes after Oocyte thaw (OOT) with and without preimplantation genetic screening (PGS), and to compare those outcomes with those of In Vitro Fertilization (IVF) with PGS. To compare clinical outcomes after Oocyte thaw (OOT) with and without preimplantation genetic screening (PGS), and to compare those outcomes with those of In Vitro Fertilization (IVF) with PGS. DesignRetrospective cohort study. Retrospective cohort study. Materials and Methods270 previously cryopreserved oocytes from 15 patients (27-42 years) were thawed/warmed, fertilized, cultured to blastocyst, and underwent trophectoderm biopsy on days 5 or 6 for analysis of ploidy by array comparative genomic hybridization (a-CGH) prior to transfer (OOT/PGS). 96 blastocysts were analyzed for ploidy. Only normal euploid embryos were transferred of embryos biopsied on days 5 or 6. OOT/PGS cycle outcomes were compared with 646 previously cryopreserved oocytes (OOT/No PGS) from 67 patients as well as 1416 blastocysts analyzed by a-CGH from 233 IVF/PGS cycles. Only patients’ first OOF /thaw (or warming) /PGS or IVF/PGS cycles were included. Donor egg cases were excluded from analysis. Cryopreservation and IVF/PGS cycles occurred between February 2007 and January 2014, thaw or warming cycles between June 2010 and March 2014. Outcomes included implantation rate (IR), clinical pregnancy rate (CPR) and ongoing pregnancy rate (OPR). CPR was defined by ultrasound-visualized sac. Patient cycle parameters were compared. ANOVA and X2 were used for analysis (p<0.05). 270 previously cryopreserved oocytes from 15 patients (27-42 years) were thawed/warmed, fertilized, cultured to blastocyst, and underwent trophectoderm biopsy on days 5 or 6 for analysis of ploidy by array comparative genomic hybridization (a-CGH) prior to transfer (OOT/PGS). 96 blastocysts were analyzed for ploidy. Only normal euploid embryos were transferred of embryos biopsied on days 5 or 6. OOT/PGS cycle outcomes were compared with 646 previously cryopreserved oocytes (OOT/No PGS) from 67 patients as well as 1416 blastocysts analyzed by a-CGH from 233 IVF/PGS cycles. Only patients’ first OOF /thaw (or warming) /PGS or IVF/PGS cycles were included. Donor egg cases were excluded from analysis. Cryopreservation and IVF/PGS cycles occurred between February 2007 and January 2014, thaw or warming cycles between June 2010 and March 2014. Outcomes included implantation rate (IR), clinical pregnancy rate (CPR) and ongoing pregnancy rate (OPR). CPR was defined by ultrasound-visualized sac. Patient cycle parameters were compared. ANOVA and X2 were used for analysis (p<0.05). ResultsTabled 1Clinical outcomes from OOF cycles with and without PGS in comparison to IVF cycles with PGSOOT with PGS (n=15)OOT without PGS (n=67)IVF with PGS (n=233)p-valueImplantation Rate50%25%66%0.0004*Clinical pregnancy rate53%45%69%0.0016*Live birth and ongoing pregnancy rate60%43%64%0.0047* Open table in a new tab ConclusionPGS in conjunction with OOT yields IR, CPR and OPR comparable to those observed for IVF/PGS. Due to the preliminary nature of this work, we expect ongoing data will reinforce conclusive significance for OOT/PGS application. PGS in conjunction with OOT yields IR, CPR and OPR comparable to those observed for IVF/PGS. Due to the preliminary nature of this work, we expect ongoing data will reinforce conclusive significance for OOT/PGS application.