O-175 Failed thaw cycles (FThC) as a key performance indicator (KPI): accounting for patient diagnosis and preimplantation genetic testing (PGT)
Authors: Wirka K , Collares F , Mahony M.C , Hayward B , Modrzejewski K , Macalino G , Byrne M , Glancey M , Catherino A.B 
Published: June 2022

Study question

Does the presence of a specific infertility diagnosis, in addition to PGT, impact FThC and live birth rate (LBR)?

Summary answer

Infertility diagnoses (Dx) and PGT should be taken into consideration when developing and/or evaluating FThC KPIs.

What is known already

FThC (ie, percentage of thaw procedures that failed to produce any embryos suitable for transfer) has been suggested as a KPI for laboratory competency in freezing/thawing procedures. Previous analyses showed that PGT (including testing for aneuploidy, monogenic/single gene defects, and structural chromosome rearrangements) was associated with improved proportions of FThC and LBRs. Here, we examined whether the presence of specific Dx could further impact the extent of improvement related to PGT on FThC and LBR.

Study design, size, duration

Retrospective real-world data analyses were performed using 6 years of available data from the Society for Assisted Reproductive Technology (SART) United States Registry between 2014–2019. Data analyses, including a descriptive review, focused on the following 5 Dx: diminished ovarian reserve (DOR), endometriosis (E), ovulatory dysfunction (OD), male factor (MF), and unknown factor (UF). These Dx were chosen based on the high prevalence of thaw cycles and/or historical difficulty to treat.

Participants/materials, setting, methods

A total of 9393 thaw cycles were analyzed, including the first transfer ≥12 months after retrieval, second transfer, or later transfers, given the database output limitation (fresh and frozen transfers taking place &lt;12 months combined). Fisher’s Chi Square was used to identify differences between PGT use over time, as well as FThC stratified by age and PGT status. Linear regression was used to determine test of trend over time for LBRs.

Main results and the role of chance

FThC improved for all Dx from 2014 to 2019, except for OD. PGT use increased significantly from 2014 to 2019 for all Dx (p &lt; 0.0001), with the greatest increase observed for DOR (10.40% vs 40.52%), UF (6.97% vs 36.20%), and MF (4.68% vs 28.67%). With PGT, across Dx, only DOR showed significant difference in the proportion of FThC from 2014 to 2019 (4.37% to 0.39%; p &lt; 0.0001), compared with data without PGT (1.77% to 1.60%; p = 0.8043). Patients with DOR had the highest average proportion of FThC (all years: PGT, 0.98%; non-PGT, 1.69%). Patients with UF had the lowest average proportion of FThC with PGT, followed by those with E and MF; however, over time, the proportion of FThC for these three Dx significantly changed without PGT (2014 vs 2019): UF, 1.17% vs 0.55% (p = 0.0008); E, 1.82% vs 0.55% (p = 0.0108); MF, 1.56% vs 0.64% (p &lt; 0.0001). Interestingly, OD showed no significant difference over time regardless of PGT status. LBRs for all Dx improved over time (p &lt; 0.0001), with higher LBR observed with versus without PGT (DOR, 47.13% vs 30.19%; E, 49.83% vs 40.84%; MF, 51.74 vs 43.74%; UF, 47.88% vs 41.13%; OD, 42.77% vs 39.42%). Consistent with FThC, OD showed the smallest improvement in LBR.

Limitations, reasons for caution

Lower numbers of FThC with PGT may limit interpretability. Presence of specific Dx in this dataset did not exclude other Dx. Clinics should review internal data to develop FThC KPI values. In the absence of internal data, SART data could be used as a reference, considering patient/cycle factors and confounders.

Wider implications of the findings

This is the first study evaluating the impact of specific Dxs and PGT on FThC. FThC as a KPI can guide embryo thawing performance goals and help set clinicians and patients’ expectations regarding the percentage of FThC along with a specific Dx and PGT status.

Trial registration number

Not applicable