Preimplantation genetic screening: who benefits?

ObjectiveTo compare IVF outcomes between women undergoing frozen transfers of blastocysts verified as euploid by preimplantation genetic screening (PGS) with patients undergoing fresh nonbiopsied blastocyst transfers.DesignRetrospective cohort study.SettingAcademic medical center.Patient(s)All patients undergoing IVF-PGS cycles between January 2010 and November 2014 were included (n = 274). Patients were compared with a control group consisting of all fresh blastocyst transfers that occurred during the same period (n = 863).Intervention(s)Patients underwent IVF-PGS with 24-chromosome screening. Patients with euploid embryos had transfer of one to two embryos in a subsequent frozen ET cycle.Main Outcome Measure(s)Implantation, clinical intrauterine gestation (CIG), miscarriage, biochemical pregnancy (BC), and live birth (LB) rates were compared.Result(s)Odds ratios (ORs) were estimated for outcomes in women undergoing PGS versus controls. Among patients ≤37 years old, there were no differences in CIG and LB rates for single (adjusted ORs [aORs], 1.20 [95 %confidence interval {CI}, 0.66-2.21]; 1.21 [95% CI, 0.66-2.2]) and double ETs (aORs, 1.09 [95% CI, 0.54-2.18]; 0.87 [95% CI, 0.44-1.7]). BC and miscarriage rates were also similar. For patients >37 years old, CIG and LB rates were increased for single (aORs, 3.86 [95% CI, 1.25-11.9]; 8.2 [95% CI, 2.28-29.5]) and double ETs (aORs, 9.91 [95% CI, 2.0-49.6]; 8.67 [95% CI, 2.08-36.2]) with no difference in BC and miscarriage rates. A per-retrieval analysis of the >37 group failed to demonstrate any difference in CIG or LB rates.Conclusion(s)Among patients ≤37, IVF-PGS does not improve CIG, LB, and miscarriage rates. IVF-PGS in women >37 improved CIG and LB rates. However, per cycle, the PGS advantage in this age group does not persist.