Immediate application of frozen-thawed embryo transfer cycle in month following COVID-19 recovery does not impair ongoing pregnancy outcome

Objective To investigate whether immediate frozen-thawed embryo transfer (FET) in the next month following coronavirus disease 2019 (COVID-19) recovery affects ongoing pregnancy outcome. Methods This was a retrospective cohort study carried out at a university-affiliated reproductive medicine center. The study group (post-COVID-19 group) comprised women who were affected by COVID-19 in December 2022 and immediately underwent FET in January 2023 after recovery, with transferred embryos not exposed to the infection. The control group comprised women treated during the pre-COVID-19 period (January 2019). Multivariable logistic regression analysis and a propensity score matching (PSM) approach were used to control potential confounders and selection bias. Results A total of 200 women were included in the post-COVID-19 group and 641 women were enrolled in the control group. The rate of ongoing pregnancy was comparable between the study cohorts in both the unadjusted and confounder-adjusted logistic regression models. Other reproductive outcomes, including the odds of a positive pregnancy test, implantation, clinical pregnancy and early pregnancy loss, were similar between the comparison groups. PSM models further confirmed the lack of significant differences in pregnancy outcome between the post-COVID-19 group and the control group. Conclusions Among patients affected by COVID-19 for whom the transferred embryos were generated prior to infection, an immediate FET cycle in the next month after recovery does not seem to compromise ongoing pregnancy outcome. Thus, women who have frozen embryos from preinfection cycles should be counseled and encouraged to undergo FET as soon as possible after COVID-19 recovery. (c) 2024 International Society of Ultrasound in Obstetrics and Gynecology.