Obstetrics and Gynaecology - Research Publications

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    Polygenic risk score for embryo selection-not ready for prime time
    Polyakov, A ; Amor, DJ ; Savulescu, J ; Gyngell, C ; Georgiou, EX ; Ross, V ; Mizrachi, Y ; Rozen, G (OXFORD UNIV PRESS, 2022-09-30)
    Numerous chronic diseases have a substantial hereditary component. Recent advances in human genetics have allowed the extent of this to be quantified via genome-wide association studies, producing polygenic risk scores (PRS), which can then be applied to individuals to estimate their risk of developing a disease in question. This technology has recently been applied to embryo selection in the setting of IVF and preimplantation genetic testing, with limited data to support its utility. Furthermore, there are concerns that the inherent limitations of PRS makes it ill-suited for use as a screening test in this setting. There are also serious ethical and moral questions associated with this technology that are yet to be addressed. We conclude that further research and ethical reflection are required before embryo selection based on PRS is offered to patients outside of the research setting.
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    Applying plastic surgery principles to ovarian tissue transplantation
    Shen, AY ; Rozen, WM ; Polyakov, A ; Stern, K ; Rozen, G (AME PUBLISHING COMPANY, 2021-07)
    Ovarian tissue cryopreservation (OTC) and transplantation is an innovative procedure increasingly utilized to help preserve fertility after gonadotoxic treatments especially in cancer patients. Approximately 30% of autotransplanted patients are able to achieve live birth, typically with the help of in-vitro fertilization. Numerous techniques and grafting sites have been described to continue to increase this figure. In the field of plastic surgery, tissue grafting has been successful performed for thousands of years and knowledge in this area has been significantly refined. A qualitative review of the literature using PubMed, Cochrane, SCOPUS and Medline databases was performed to look for articles relating to ovarian tissue transplantation (OTT) and comparisons made to plastic surgery tissue grafting. Many parallels were found between the principles of grafting in plastic surgery and the principles of OTT, including pre-operative patient optimization, suitable donor site selection, tissue harvest and preparation, graft site choice, immobilization of the graft and post-operative care. Consideration of the benefits and risks of using orthotopic versus heterotopic recipient sites is also highly important with regards to graft take, morbidity and ease of access of oocyte collection. We believe that ongoing discussion between disciplines can have the potential to improve knowledge, surgical techniques and patient outcomes.
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    Comparing pregnancy outcomes between natural cycles and artificial cycles following frozen-thaw embryo transfers
    Pakes, C ; Volovsky, M ; Rozen, G ; Agresta, F ; Gardner, DK ; Polyakov, A (Wiley, 2020-10)
    Background Frozen embryo transfer (FET) is increasing in prevalence. In contrast to the amount of research performed on the actual cryopreservation procedure, there are limited data with respect to optimal endometrial preparation in FET cycles. Increasingly artificial cycle (AC) preparation is being adopted over the natural cycle (NC) to facilitate greater access to FET. However, there remains a paucity of data comparing pregnancy outcomes between these two commonly used cycle types. Aims To examine the efficacy of AC vs NC following FET, by comparing pregnancy outcomes including biochemical, clinical and live birth rates, along with miscarriage rates. Materials and Method This is a large single‐centre retrospective analysis, examining a standardised data set from January 2015 to July 2018. It included 3030 cycles (NC = 2033, AC = 997). Main outcomes were biochemical pregnancy (beta‐human chorionic gonadotropin > 5 IU), ultrasound‐diagnosed clinical pregnancy, and live births. Using the χ2 test, the above pregnancy outcomes were compared between AC and NC. A multivariate logistic regression, controlling for factors such as age, embryo quality, and day of blastocyst freeze was further utilised to assess for confounding variables. Results No difference was observed between biochemical pregnancy rates (NC = 39.45% vs AC = 37.71%, P = 0.357); statistically significant differences were observed between clinical pregnancy (30.84% vs 26.08%, P = 0.007), and live birth rates (24.40% vs 18.86% P = 0.001). Multivariate analysis confirmed that NC produces superior pregnancy outcomes when controlling for confounding variables. Conclusion This analysis demonstrates the non‐inferiority of NC thaw compared to AC, on continuing pregnancy rates. Taken together with patient acceptability and possibly increased obstetric risks with AC, these findings support the use of NC when medically possible.
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    Is it possible to apply trial outcomes to a real-world population? A novel approach to External Validity Analysis
    Agresta, F ; Fois, R ; Garrett, C ; Rozen, G ; Polyakov, A (WILEY, 2020-04)
    BACKGROUND: Translation of findings from randomised controlled trials (RCT), the foundation of evidence-based medicine, into clinical practice requires an understanding of relationships between patient characteristics, treatment practices and outcomes. We propose a novel technique, External Validity Analysis (EVA), to evaluate applicability of findings from a large RCT, comparing baseline characteristics, interventions and outcomes between the RCT and a large clinical database. AIM: To perform EVA of the findings of a randomised controlled trial (ESTHER-1) to a population in an Australian clinic setting. To demonstrate this method, we evaluated the discordance in first cycle follicle-stimulating hormone (FSH) exposure and outcomes between the two populations, to inform clinical practice. MATERIALS AND METHODS: In this retrospective, descriptive analysis, we compared practices and outcomes between the follitropin alfa 'conventional' dosing arm of the ESTHER-1 trial and a selected comparable clinic subpopulation of patients who underwent controlled ovarian stimulation using FSH. RESULTS: Mean FSH exposure was 34% higher in the clinic subpopulation than in the trial subpopulation, resulting in higher average ovarian response without improving the likelihood of clinical pregnancy or live birth. CONCLUSIONS: EVA allowed for the comparison of a trial population with a selected clinic population with similar characteristics. With respect to FSH consumption, this analysis revealed higher exposure to FSH in the clinic setting without a corresponding benefit. The comparison reveals population differences as well as the potential to improve clinical outcomes through a reappraisal of current practices and objectives in gonadotropin dose selection.