P-518 The effect of inactivated SARS-CoV-2 vaccination on the outcome of the first frozen-thawed embryo transfer cycle

Abstract Study question Is there an effect of inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination on the outcome first frozen-thawed embryo transfer(FET) cycle. Summary answer Inactivated SARS-CoV-2 did not affect FET cycle, including clinical pregnancy rate, early miscarriage rate and newborns’ birth weight. What is known already can significantly reduce risk disease death after infection. However, due to lack vaccine safety data, infertile population who plan undergo ART treatment have high concerns about vaccination. To date, are merely few researches aimed determine impact reproductive neonatal outcomes women attempting FET. design, size, duration This was a retrospective cohort study patients underwent cycle in Reproductive Center Ningbo Women Children Hospital from November 1st 2021 December 19th 2022. All were followed up until January 2023. Patients whose age >40 years old excluded. The organized into groups based age, anti-Müllerian hormone (AMH) levels, antral follicle count (AFC), body mass index (BMI), or not. Participants/materials, setting, methods fully vaccinated with two doses Sinopharm Sinovac vaccines(Group A, n = 452) compared unvaccinated patients(Group B, matched by AMH, AFC BMI. baseline characteristics each group compared.SPSS version 26.0 (SPSS Inc., USA) used for all data analyses. Main results role chance There no statistically significant differences AFC, BMI, infertility duration, type, causes, fertilization ovarian stimulation protocol, number oocytes retrieved(9.24 vs 9.92, p 0.102), endometrial preparation thickness(9.40 9.29mm, 0.344), stage, embryos transfer(1.4 1.42, 0.589) between groups. No difference found rate(55.31% 57.52%, 0.502), rate(10.4% 11.54%, 0.681). weight comparable groups(2971.44 3156.83g, 0.66). Limitations, reasons caution single-center further accumulated warranted validate findings. Because short follow-up time, some still pregnant, hence we await live outcomes. Wider implications findings These contribute evidence regarding fertility-seeking women, it provide theoretical reassurance doctors vaccinate before pregnancy. Trial registration applicable