Ovation Fertility

Infertility affects 1 in 6 couples, yet male fertility assessments often rely on semen analysis alone, which has limited predictive value for treatment success. This study evaluates an epigenetic tool for assessing sperm quality, aiming to provide a more comprehensive view of male fertility and improve personalized treatment strategies. De-identified pregnancy outcomes from 537 couples treated at 10 US fertility clinics were analyzed. Partner ages, total motile sperm count, treatment type, and sperm epigenetic quality were considered to assess associations with fertility treatment outcomes. Men with abnormal sperm epigenetic profiles had significantly lower pregnancy success rates with intrauterine insemination (IUI) compared to those with normal profiles, despite similar sperm motility and concentration. In contrast, pregnancy rates did not differ between abnormal and normal profiles among couples undergoing in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI), suggesting that ICSI may overcome sperm epigenetic quality issues. This real-world analysis was limited by the availability of detailed clinical and phenotypic data, which may introduce potential confounders. Nevertheless, the findings highlight the clinical value of epigenetic sperm assessment as part of male fertility evaluation and support its potential to guide more effective, personalized fertility treatment pathways.

Adjuvant endocrine therapy (AET) reduces the risk of breast cancer recurrence, but racial differences in nonadherence persist, potentially reflecting variations in symptom burden. We conducted a post hoc analysis of the THRIVE trial to investigate symptom burden and AET adherence by race among women with early-stage breast cancer. We included Black and White women who enrolled in the THRIVE trial, a remote monitoring intervention, from November 2018 to June 2021. Participants completed surveys at baseline and at months 6 and 12, including symptom burden measured using the Functional Assessment of Cancer Therapy-Endocrine Subscale (FACT-ES) instrument. Adherence was defined as the proportion of days covered >80% using an electronically monitored pillbox. Multivariable regression analyses were performed to examine factors associated with adherence, and Kitagawa-Oaxaca-Blinder decomposition was used to quantify the proportion of adherence differences explained by symptom and patient characteristics. Among 102 (34.7%) Black and 192 (65.3%) White women randomized to 3 study arms evaluating the efficacy of the remote monitoring intervention, 84% completed the 6-month survey, and 87% completed the 12-month survey. Black participants were younger and had lower income and health literacy (P<.01). Black women reported worse symptoms at baseline (60.9 vs 64.4; P=.003) and month 12 (57.0 vs 61.9; P<.001), yet a similar proportion experienced 5-point decreases (the minimally important difference) over the 12-month period (34.9% vs 32.4%; P=.69), compared with White women. At month 12, fewer Black participants were adherent to AET than White participants (43.0% vs 60%; difference=17.0 percentage points [ppts]; P=.009). This difference was attenuated after adjusting for symptoms and patient characteristics (-7.75 ppts; P=.34). Baseline symptoms (0.77 ppts; P=.021) were significantly associated with adherence over 12 months, whereas changes in symptoms were not (0.14 ppts; P=.69). Symptom and patient characteristics together accounted for 58% of the 1-year adherence difference between racial groups. Black women had lower 1-year AET adherence compared with White women, largely attributed to baseline symptoms and sociodemographic characteristics. More proactive symptom management and addressing social determinants of health among Black women may alleviate disparities in AET adherence. gov Identifier: NCT03592771.

Abstract Study question Does PPOS lead to higher oocyte yield and euploid conversion rates compared to the antagonist protocol, and does it compromise oocyte DNA integrity? Summary answer PPOS increases mature oocyte yield and euploid conversion rates per oocyte, but higher segmental aneuploidy rates raise concerns about potential DNA damage, warranting further investigation. What is known already Progestin-Primed Ovarian Stimulation (PPOS) is a viable alternative to antagonist protocols, offering cycle scheduling flexibility with comparable pregnancy outcomes. While some studies suggest similar embryological outcomes, limited data exist on oocyte quality, euploid conversion efficiency, and potential DNA damage. Understanding whether PPOS enhances oocyte retrieval while preserving DNA integrity is critical for optimizing individualized ovarian stimulation protocols. Study design, size, duration This retrospective cohort study was conducted at Ovo Clinic, a university-affiliated private fertility center in Montreal, Canada, analyzing 449 IVF with PGT-A cycles performed in 2023 and 2024, comparing 24 PPOS cycles with 425 antagonist cycles under the same laboratory and clinical conditions. Participants/materials, setting, methods Patients were categorized into PPOS (n = 24) and antagonist (n = 425) groups. Parameters assessed included baseline age, AMH, mature oocyte yield, euploid embryo rates, and aneuploidy rates. Quantitative variables were compared using parametric or non-parametric test depending on their distribution. Qualitative variables were assessed using the chi-square or Fisher’s exact test. A p-value &amp;lt; 0.05 was considered statistically significant. Main results and the role of chance Baseline characteristics were comparable between groups (age: 37.7 ± 2.9 vs. 37.7 ± 3.7 years, p = 0.48; AMH: 3.4 ± 2.7 vs. 3.1 ± 2.7 ng/mL, p = 0.56). PPOS yielded more mature oocytes (16.0 ± 12.4 vs. 11.8 ± 6.8, p = 0.18) and demonstrated a significantly higher euploid conversion rate per mature oocyte (29.8% vs. 12.6%, p &amp;lt; 0.001). Although euploid embryo rates per embryo were similar (44.7% vs. 44.1%, p = 0.92), segmental aneuploidy rates were significantly higher in the PPOS group (6.1% vs. 0.8%, p &amp;lt; 0.001). These findings suggest that while PPOS may improve oocyte retrieval efficiency, concerns remain regarding its potential impact on oocyte DNA integrity. One hypothesis to explore is whether oxidative stress induced by the PPOS protocol contributes to DNA damage, leading to increased segmental aneuploidies. Future studies should assess oxidative stress markers and DNA fragmentation in oocytes to determine if this mechanism is clinically relevant. Limitations, reasons for caution The small sample size in the PPOS group limits statistical power. As this is an exploratory study, larger, prospective trials with oxidative stress assessments are needed. Wider implications of the findings PPOS appears beneficial for patients requiring higher oocyte yields, but potential risks to DNA integrity must be considered. Future studies should refine patient selection criteria for its use. Trial registration number No

Alpha-fetoprotein (AFP) is measured during pregnancy in maternal serum to screen for, and in amniotic fluid to test for, neural tube defects. This study aimed to determine whether or not AFP is expressed in blastocoel fluid-conditioned media (BFCM) at the blastocyst stage of embryonic development. For this in vitro study, BFCM was obtained from blastocyst stage embryos following standard embryology laboratory processes. Good quality blastocysts (n = 40) had trophectoderm biopsy for preimplantation genetic testing for aneuploidy (PGT-A) with subsequent blastocyst vitrification and BFCM collection. BFCM samples (n = 40) were analyzed for human AFP protein via an AFP Human ELISA Kit. Statistical analysis was performed with Fisher's exact test. AFP was expressed in 12.5% (5/40) of BFCM samples (range = 1.69-20.5 pg/mL). Of blastocysts with AFP in BFCM, 80% (4/5) had aneuploid PGT-A results; of blastocysts with no AFP in BFCM, 57% (20/35) had aneuploid PGT-A results, with no difference between groups (p = 0.63). Our study demonstrates AFP expression in BFCM. To our knowledge, this is the first study to report the detection of AFP at the embryonic blastocyst stage in vitro. Future studies are needed and underway to determine whether assessment of AFP at the embryonic stage can improve embryo transfer outcomes.

45 Background: Despite the efficacy of oral adjuvant endocrine therapy (AET) for improving survival among women with hormone receptor-positive early-stage breast cancer, adherence rates remain low. Our THRIVE study (NCT03592771) investigated the effectiveness of a mobile health remote monitoring app with and without tailored educational messages on AET adherence among women with breast cancer and found no statistically significant treatment effects on 1-year AET adherence overall. Health literacy contributes to patients’ understanding of their treatment plans. We conducted a post hoc analysis of the THRIVE study to examine if health literacy moderates the effectiveness of this intervention. Methods: This non-blinded randomized controlled trial included women with early-stage breast cancer prescribed AET at a large cancer center with 14 clinics across three states. Participants used a pillbox to electronically monitor AET adherence for 1 year and completed surveys at enrollment. Consented participants were randomized into (1) “App”, receiving access to the study adherence and symptom monitoring app for 6 months, with increasing/severe symptoms and missed doses reported in the app triggering follow-ups from the oncology team; (2) “App+Feedback”, receiving additional weekly text messages about managing symptoms, adherence, and communication for 6 months; or (3) “Enhanced Usual Care (EUC).” The primary outcome was 1-year AET adherence captured with the pillbox (≥80% Proportion of Days Covered [PDC] vs. &lt; 80%). The enrollment survey captured participant’s sociodemographic characteristics, including race and ethnicity, education, household income, and health literacy. We used a linear probability model to measure the interaction between the study arm and health literacy on AET adherence. Results: Among 304 women randomized (104 EUC, 98 App, and 102 App+Feedback), the 12-month follow-up retention rate was 88% (n = 266) and 19.4% reported low health literacy at enrollment. Low health literacy was more prevalent among Black (29.4%) vs. White (13.4%) participants (p &lt; 0.001), those with incomes below the federal poverty level (34.4% vs. 17.2% of those with higher incomes, p = 0.02), and those with only a high school degree or lower education (31.7%) vs. with those with some college or higher education (16.4%, p &lt; 0.01). In the low health literacy group, 80.0% of App+Feedback were AET adherent vs. 42.1% of EUC, a 37.9 percentage point (ppt) difference (95% CI: 4.1 to 71.7, p = 0.03); in higher literacy group adherence, 47.1% of App+Feedback vs. 59.0% of EUC were adherent, a -11.8 ppt difference (95% CI: -27.9 to 4.3, p = 0.15). Conclusions: A remote monitoring app with tailored educational text messages led to higher 1-year AET adherence among participants with low health literacy, but not for those with high health literacy. Clinical trial information: NCT03592771 .

Abstract To address the need for targeted therapy in the treatment of HER3-positive solid tumors, the human HER3 mAb, seribantumab, was evaluated in the context of an antibody-drug conjugate (ADC). As a proof-of-concept, seribantumab was conjugated with a cleavable valine-citrulline linker and monomethyl auristatin E (MMAE) payload via the stochastic cysteine conjugation method to yield HER3-ADC1. A drug-antibody ratio of 4 was selected for preclinical assessment in HER3-expressing models. Methods: HER3-ADC1 was evaluated in vitro and in vivo, with patritumab deruxtecan (patri-DXd) as a comparator. Binding to BT474 breast carcinoma cells (HER3 high; immunohistochemical (IHC) staining intensity 3+) was measured by flow cytometry. Internalization properties were established using seribantumab and patritumab coupled to Fab-AF488 following 4 hours incubation in SK-BR-3 breast adenocarcinoma (HER3 high; IHC 3+) and HCC1569 breast carcinoma (HER3 low; IHC 0-1+) cell lines. In vitro cytotoxicity was evaluated for HER3-ADC1, isotype-MMAE and free MMAE payload as well as patri-DXd, isotype-DXd and free deruxtecan payload in BT474 cells, SK-BR-3 cells and NCI-H446 lung carcinoma (HER3 low; IHC 0-1+) cells. In vivo anti-tumor activity was assessed for HER3-ADC1, isotype-MMAE, patri-DXd and isotype-DXd in patient derived xenograft (PDX) models of pancreatic (HER3 high; IHC 3+) and breast cancer (HER3 low; IHC 0-1+). Results: HER3-ADC1 binding to cancer cells, endocytosis, MMAE release, and inhibition of proliferation were dependent on HER3 expression. In assays investigating antibody internalization, seribantumab displayed similar internalization capacity as patritumab. For both HER3 mAbs, internalization was greater in a HER3 high than a HER3 low cell line. In cytotoxicity assays, HER3-ADC1 and patri-DXd displayed HER3 expression level-dependent cell killing. HER3-ADC1 outperformed patri-DXd in HER3 high cell lines based on in vitro cytotoxicity. HER3-ADC1 and patri-DXd were ineffective against NCI-H466 cells with low HER3 expression. In a PDX model of pancreatic cancer (HER3 high), HER3-ADC1 induced tumor regression, while isotype-MMAE had only a moderate anti-tumor effect. Both patri-DXd and isotype-DXd had moderate anti-tumor effects, indicating a lack of HER3 target dependence. In a PDX model of breast cancer (HER3 low), HER3-ADC1 and isotype-MMAE lacked anti-tumor activity; isotype-DXd had a moderate anti-tumor effect and patri-DXd had a substantial anti-tumor effect. Conclusions: HER3-ADC1 demonstrated target-dependent in vitro cytotoxicity and in vivo anti-tumor activity in a HER3-expressing pancreatic cancer PDX model. Results from in vitro and in vivo studies highlight the promising therapeutic potential of a seribantumab-based ADC for patients with HER3-expressing cancers. Additional results on the optimization and characterization of HER3-ADC1 will be presented. Citation Format: Thomas O'Hare, Jaclyn Cleveland, Valerie M. Jansen, David Dornan. Therapeutic potential of a HER3 antibody-drug conjugate for the treatment of HER3-expressing cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3121.

Background and Aims: Embryologist evaluation of embryos is critical for ensuring successful pregnancy outcomes. Standard, manual evaluation is variable, subjective, and time-consuming. The aim of this study was to evaluate whether an artificial intelligence (AI) algorithm can standardize and improve embryo evaluation during IVF. Method: 20 images of blastocyst-stage embryos on day 5 of in vitro development were selected to represent a range of morphological qualities. All embryos had been transferred and the clinical pregnancy outcome was known for each embryo based on detection of fetal heartbeat at first ultrasound scan (∼7-9 weeks gestation). 50% of embryos in the dataset resulted in pregnancy. 158 embryologists made a total of 236 attempts at providing their evaluation of the morphological quality of the 20 embryo images using the Gardner system. The embryologist-assigned grades were then used to generate their prediction of whether that embryo would lead to pregnancy or not (≥ 3BB indicated a pregnancy prediction, and &lt;3BB indicated a non-pregnancy prediction). The same 20 embryo images were also assessed by a previously developed viability AI algorithm for evaluating the likelihood of clinical pregnancy based on embryo images. An AI score of ≥5.0/10 indicated a pregnancy prediction, and &lt;5.0/10 indicated a non-pregnancy prediction. The AI algorithm provided the same score for each embryo image regardless of how many times the analysis was performed. Results: The AI algorithm correctly predicted pregnancy outcome for 14/20 embryo images (70%). Embryologists also correctly predicted 14/20 images in 14/236 attempts (6%), and in 1 attempt correctly predicted 15/20 images. In the remaining 221 attempts (94%) embryologists correctly predicted between 6-13 images, representing a range of accuracies from 30-75%. Conclusion: This study demonstrates the inherent variability and lack of objectivity associated with an embryologist’s evaluation of embryos. It highlights the benefits of accurate AI algorithms for standardizing embryo assessment

Abstract Study question Are there differences in fertilization, blastocyst development, or euploidy rates when comparing ICSI versus conventional insemination among patients with male and non-male factor infertility? Summary answer Fertilization rate was lower for male factor ICSI. There were no differences in blastocyst development. Euploidy rate was lower for non-male factor ICSI. What is known already ICSI was developed for male factor infertility due to its requirement for a very small number of viable sperm. Its use has expanded beyond male factor due to some studies suggesting enhanced fertilization, and lower risks of failed fertilization or inadvertent contamination of embryo biopsy specimens. There are potential risks associated with ICSI, including imprinting disorders, birth defects, and significantly increased cost. It is also unclear whether ICSI contributes to genetic abnormalities by bypassing the egg’s natural sperm selection and potentially disrupting the meiosis apparatus. Study design, size, duration This retrospective cohort study of 576 patients was conducted at a single clinic from January 2021 to December 2021. Patients were grouped into (1) ICSI with male factor (n = 201), (2) ICSI with non-male factor (n = 160), and (3) conventional insemination with non-male factor (n = 215). Primary outcome was ploidy status, determined by calculating the percentage of euploid, aneuploid, and mosaic (both low and high mosaic) among the three groups. Secondary outcomes included fertilization and blastocyst development rates. Participants/materials, setting, methods Patients undergoing autologous IVF at a single clinic, with PGT-A performed at a single lab were included. Fertilization rate was defined as the percentage of 2PNs per number of mature eggs injected/inseminated. Blastocyst rate was defined as the percentage of blastocysts per 2PNs. Ploidy rate was defined as the percentage of euploid/aneuploid/mosaic blastocysts per total biopsied blastocysts for which a result was obtained. Percentage data was compared using N-1 Chi-squared test. Main results and the role of chance There were no significant differences in patient age, number of oocytes retrieved, or number of mature oocytes among the three groups. Fertilization rate for male factor ICSI was significantly lower compared to both non-male factor ICSI (74.2% vs 77.8%, p = 0.005) and conventional insemination (74.2% vs 76.8%, p = 0.018). There was no significant difference in fertilization rate between non-male factor ICSI and conventional insemination. There were no significant differences between blastocyst rates on Day 5, 6, or 7, or total blastocyst rate among the three groups. The euploidy rate for conventional insemination was significantly higher than that for non-male factor ICSI (53.4% vs 46.8%; p = 0.008). Non-male factor ICSI yielded lower euploidy rate than male factor ICSI (46.8% vs 52.4%, p = 0.034). Aneuploidy rate for non-male factor ICSI was significantly higher than both male factor ICSI (36.1% vs 31.0%, p = 0.041) and conventional insemination (36.1% vs 31.0%, p = 0.030). Mosaicism levels were similar between the three groups. There were no significant differences in number of biopsied embryos with no results: 5 for ICSI male factor group (0.59%), 6 for ICSI non-male factor (0.96%), and 10 for conventional insemination (0.89%). Limitations, reasons for caution This was a retrospective analysis of patients from a single clinic, with a relatively small sample size so results may not be generalizable to all populations. Extensive demographic information and baseline characteristics (including reason for ICSI performed among non-male factor patients) were not analyzed so there may be confounding factors. Wider implications of the findings This is the first study that we are aware of to investigate the ploidy status of embryos created among non-male factor patients undergoing ICSI. Conservative use of ICSI can significantly decrease the cost of IVF. Larger studies are needed to further elucidate the role for ICSI among these patients. Trial registration number not applicable

Abstract Study question How does the embryo morphological grade and day of vitrification affect FET outcomes from in vitro fertilization cycles utilizing preimplantation genetic testing for aneuploidy (PGT-A)? Summary answer The morphological grade of a transferred embryo affects FET outcomes in age groups differently, and Day-5 embryos have significantly better pregnancy outcomes than Day-6 embryos. What is known already The use of PGT-A has shown to increase implantation rates, lower miscarriage rates and promote counseling for a single embryo transfer. Although euploid embryos are the priority for transfer, it is important to examine embryo characteristics that may influence these outcomes within these euploid embryos to maximize the outcome for each FET. Study design, size, duration In this retrospective study, 1,554 FETs transferring one euploid Day-5 or Day-6 embryo between January 2020 and October 2022 were evaluated, with the exclusion of donor oocyte, donor embryo, gestational carrier and Day-7 embryo transfer cycles. The inner cell mass and trophectoderm were each categorized as good (G), fair (F) or poor (P) respectively at the time of embryo cryopreservation. A total of 282 GG, 1,053 FG, and 209 FF embryos were transferred. Participants/materials, setting, methods Embryo grade categories were used to compare Day-5 versus Day-6 transfer outcomes and by age groups. Separating groups as &amp;lt; 34, 34-37, and ≥38 eliminated age as a significant factor. Primary outcomes included rates of positive chemical pregnancy (CP), biochemical loss (BL), clinical uterine gestation (CIG), and fetal cardiac activity (FCA). Independent t-tests compared age, and aggregate data was analyzed by proportional z-tests. A p-value &amp;lt;0.05 was defined as statistically significant with a 95% confidence interval. Main results and the role of chance Age and BL were not significant between transfer days or age groups. Day-5 had higher CP (GG: 84% vs 65%, p &amp;lt; 0.001; FG: 75% vs 59%, p = 0.006; FF: 63% vs 44%, p = 0.019), CIG (GG: 73% vs 57%, p = 0.006; FG: 64% vs 48%, p &amp;lt; 0.001; FF: 55% vs 34%, p = 0.007), and FCA (GG: 66% vs 52%, p = 0.022, FG: 60% vs 40%, p &amp;lt; 0.001, FF: 55% vs 30%, p &amp;lt; 0.001). For patients &amp;lt;34, GG had higher CP compared to FG and FF (74% vs 64%, p = 0.017; 74% vs 46%, p &amp;lt; 0.001), CIG (66% vs 55%s, p = 0.011; 66% vs 38%, p &amp;lt; 0.001) and FCA (61% vs 50%, p = 0.012; 61% vs 38%, p = 0.001). FG had higher CP (64% vs 46%, p = 0.007) and CIG (55% vs 38%, p = 0.008) compared to FF. For patients 34-37, GG and FG had higher CP (78% vs 53, p &amp;lt; 0.001; 70% vs 53%, p = 0.004), CIG (66% vs 42%, p = 0.002; 56% vs 42%, p = 0.029), and FCA (58% vs 35%, p = 0.002; 50% vs 35%, p = 0.011) compared to FF. When compared to FF in patients ≥38, GG and FG had increased CP (79% vs 47%, p &amp;lt; 0.001; 64% vs 47%, p = 0.012) and CIG (65% vs 36%, p = 0.004; 53% vs 36%, p = 0.010). Only GG had higher FCA (56% vs 36%, p = 0.049). Limitations, reasons for caution Even with the exclusion criteria, the retrospective nature of the study may be viewed as a limitation, so the significance of the results should be evaluated further. Wider implications of the findings Based on these results, this study demonstrates the need to compare the characteristics of euploid embryos before selection to maximize the chance of pregnancy. Embryos vitrified on Day-5 or categorized as GG, especially in patients &amp;lt;34, or FG should be prioritized over Day-6 or FF embryos. Trial registration number not applicable

Abstract Study question Data on random start letrozole ovarian stimulation (RSL) in breast cancer patients is scant. We studied RSL outcomes from a single-center with fertility preservation expertise. Summary answer RSL appears to result in high oocyte and embryo/blastocyst yield, with an age-appropriate aneuploidy rate. What is known already With increasing utility of neoadjuvant chemotherapy regimens in breast cancer, young women have limited time to undergo fertility preservation (FP) by oocyte or embryo cryopreservation. Random start stimulation protocols were developed to complete an ovarian stimulation cycle in the shortest time possible before cancer patients started chemotherapy. In addition, letrozole protocols were developed to mitigate the potential risks of high estrogen levels during ovarian stimulation in breast cancer patients. Even though both random start and letrozole supplemented ovarian stimulation have been studied individually, there is limited data on combining both strategies in random start letrozole (RSL) protocols. Study design, size, duration We reviewed our records from 2014 to 2021. We included the first FP cycle of all breast cancer patients undergoing RSL ovarian stimulation for oocyte or embryo cryopreservation. Cancer stages were grouped as 0-4, 0 being ductal carcinoma in situ (DCIS). Twenty-eight cycles met the criteria. Main outcome measures were number of oocytes retrieved and embryos cryopreserved. Secondary outcome measures were fertilization, blastocyst, and euploidy rates for the embryo cryopreservation group. Participants/materials, setting, methods Ovarian stimulation began on cycle days 3-26 with letrozole 5 mg/day initiated simultaneously with rFSH. The rFSH dose was based on age and antral follicle counts (AFC). Oocyte maturation was triggered with leuprolide acetate, rhCG or both 35h prior to retrieval. Main results and the role of chance The mean age was 33.5±4.9 years (range 26-40) and BMI 22.3±2.9(18.4-30.3). The mean breast cancer stage at FP was 1.7±0.9 (0-4), with 42.3% being stage-I disease. 77% of cases were estrogen receptor positive. AMH was 2.7±2.4 (0.16-7.9) and AFC 18.5±8.9(4-42). Ovarian stimulation began on cycle-day 13.7±7.3(2-26). 15(54%) cycles were started in the follicular and 13(46%) in the luteal-phase. The mean total rFSH dose was 3880±1615.4 IU(1275-8325) with a stimulation length of 11.8±2.4 days(8-19). Mean oocytes retrieved were 16.4±6.9(1-36) with a maturity rate of 71.4±17.9%(35.7-94.4). From 13 patients, 10.4±4.7(1-22) oocytes were cryopreserved. Among the 15 patients proceeding to embryo cryopreservation, the fertilization rate was 96.9±6.8%(80-100), resulting in 7.1±4.4(1-15) embryos. 24 embryos were cryopreserved on day-3 and 82 as blastocysts. PGT-A was performed in 72% of the cases, with euploidy rate of 37.7±24.4%(0-63.6). There was no difference in oocyte or embryo yield between follicular and luteal start patients. Likewise, fertilization rates and euploidy rates were similar. The comparative results are summarized in Table 1. To date, two patients conceived utilizing cryopreserved embryos. Both pregnancies resulted in healthy term babies. Limitations, reasons for caution Though our report is one of the largest series of RSL, it can be strengthened with longer follow up that includes pregnancy outcomes in a greater proportion of patients. Wider implications of the findings This is the first detailed report of the RSL protocol utility with PGT-A results in a breast-cancer population. RSL appears to result in high oocyte-yield, fertilization, and blastocyst formation rates, with age-appropriate euploidy. Additionally, the outcomes appear to be similar between patients undergoing follicular and luteal phase start RSL. Trial registration number not applicable