Fresh vs. frozen donor oocytes (DO) - looking at the big picture, is one superior?

Abstract

Since the first reported birth in 1983, many children have been born using DO. Donated sperm is mostly frozen, quarantined and purchased from banks; however, using FRESH female gametes has long been viewed as the gold standard in DO. As FROZEN DO banks have emerged in recent years, using FROZEN DO has become common, changing the treatment-process model. The use of FROZEN DO may simplify logistics and allow recipients more choices as well as lower infection risk, time pressures and/or cost. Thus, we aimed to compare outcomes and processes using FRESH vs commercially-banked FROZEN DOs at our program. Retrospective cohort at a single large university program. We reviewed all FRESH and FROZEN DO cycles from 1/1/2015 - 12/31/2017. Cycles with and without preimplantation genetic testing for aneuploidy (PGT-A) were included. Primary outcomes were clinical pregnancy rate (CPR) and ongoing pregnancy (>12 weeks gestation) / live birth rate (LBR). See Table. 164 FRESH (126 w ET) + 67 FROZEN (64 w ET) DO cycles were evaluated. Notably, significantly more oocytes were available for use in FRESH vs. FROZEN cycles (21 vs. 7, p<.0001). 2PN fertilization was similar (p=.9), whereas Blastocyst Utility (BUR; transferred + frozen) was greater in FRESH (p=.002). PGT-A was performed in 119/164 (73%; 93 w ET) FRESH, but only 6/67 (9%; 5 w ET) FROZEN. In non-PGT-A cycles, CPR and LBR for FIRST embryo transfer (ET) were similar. In PGT-A cycles, CPR was not different, but LBR was higher for FRESH than FROZEN (p=0.01). When comparing non-PGT-A to PGT-A FRESH, CPR and LBR were not different (p=1). Total annual program costs for recruiting, screening, stimulating and retrieving 65 FRESH DO cycles was $644,645, (thus, single usable donor cost was $9900: Meds $4200, Staffing $2331, Cycle Treatment $1954, Labs $1415). In contrast, one batch (6) of banked FROZEN DOs costs ∼$15,000. FRESH DO cycles have the advantage of more oocytes, fresh fertilization and higher BUR. Disadvantages include recipient coordination, lower donor availability and production of more supernumerary blastocysts that may never be used. FROZEN DOs are more readily available albeit at lower oocyte numbers and have an 8% no-ET rate due to poor embryo development. PGT-A does not offer improvement in LB outcomes in DO while adding cost (as well as a second freeze and potentially lower outcome when using few FROZEN DOs). Perhaps FRESH donor “splitting” between recipients with fresh fertilization, then blastocyst freeze with subsequent frozen ET makes the most sense from a logistical, cost and efficiency standpoint. DO banks remain a viable option.Tabled 1FRESH vs. Commercially-Banked FROZEN DO. Mean no. of blastocysts (BL) transferred/cycle=1 for both.FRESH DO (n=174; mean no. oocytes used/cycle=21)FROZEN DO (n=67; mean no. oocytes used/cycle=7)P Value (mean no. oocytes used/cycle: <0.0001)2PN Fertilization Rate2295/2939 (78%)327/420 (78%)0.90BUR/2PN1485/2317 (64%)180/327 (55%)0.002Non-PGT-A Cycles n (n with ET)**In these cycles, 0/33 (0%) FRESH vs. 5/60 (8%) FROZEN were cancelled for poor embryo development33 (33)60 (59)CPR for FIRST ET22/33 (67%)36/59 (61%)0.66LBR for FIRST ET20/33 (61%)31/59 (53%)0.52No. cycles with supernumerary BL - Mean no. BL frozen32/33 (97%) - 741/59 (70%) - 20.001PGT-A Cycles n (n with ET)119 (93)7 (5)No. Cycles with at Least 1 Euploid BL115/119 (97%)6/7 (86%)0.25Euploid BL / Biopsied BL534/1050 (51%)12/22 (55%)0.83CPR for FIRST ET62/93 (67%)1/5 (20%)0.053LBR for FIRST ET56/93 (60%)0/5 (0%)0.01 Open table in a new tab