Dados do Trabalho

Title

Type of SARS-CoV-2 vaccine does not affect embryo development outcomes in assisted reproduction

Objective

During the SARS-CoV-2 vaccination campaign in Brazil, 4 main types of vaccines have been administered: Pfizer/BioNTech, Sinovac-CoronaVac, FioCruz/AstraZeneca, and Janssen Pharmaceuticals. Pfizer vaccine is an mRNA-based vaccine that do not contain live viral particles, Fiocruz/AstraZeneca and Janssen vaccines are based on the action of adenoviruses, which do not have replicative activity and can stimulate the immune response without the presence of adjuvants and Sinovac-CoronaVac is an inactivated whole-virion SARS-CoV-2 vaccine. The impact of vaccination and type of vaccine on fertility and health in general is the subject of numerous rumors and much contradictory information. Vaccine hesitancy has been a severe problem in eradicating the disease. Therefore, the objective of our study was to evaluate if there was an influence of the different types of SARS-CoV-2 vaccine on the embryo development outcomes of patients undergoing assisted reproduction treatment.

Methods

This was a retrospective and observational study conducted from January 2022 to December 2022 in women vaccinated against SARS-CoV-2 who underwent assisted reproductive treatment. The medical records of the patients who had received covid vaccine were retrospectively reviewed to identify the type of vaccine (mRNA vaccine, adenoviruses vaccine or inactivated SARS-CoV-2 vaccine) and the outcomes of their treatment. All data were obtained from our clinical database. We exclude all patients with severe male factor or those who use donor oocytes/sperm. Patients’ characteristics are presents as mean ± standard deviation or percentage. Data was analyzed through personalized multiple linear regression model to access vaccine type influence in embryo development outcomess. Was considered as laboratory outcomes: number of follicles, number of oocytes retrieved, number of mature oocytes, fertilization rate, blastulation rate and good quality embryos rate. Was considered as confusion variables the covariates of maternal age, BMI and infertility cause. Statistical analysis was performed with SPSS 20 (IBM- Chicago,IL,UDSA)

Results

We included 64 patients, distributed as follows: 46,8% received a mRNA vaccine (n=36), 19% (n=15) received a adenoviruses vaccine and 15% (n=12) received an inactivated SARS-CoV-2 vaccine. Also, most of the patients underwent treatment with more than 6 months after the first vaccine, only 3% underwent treatment with less than 6 months. None of the couples had any know underlying diseases. Patients included in the study present medium age of 37,6 ± 3,67 and BMI 23,45 ± 3,30, search for treatment was primarily for female reasons (20% Endometrioses, 17% Anatomic factor, 23% Endocrine factor, 11% ovarian insufficiency, 13% male factor, 3% ESCA and 13% other factors). Laboratory rates follow the recommended by the Vienna Consensus. Our data analyses show no influence of type of SARS-Covid vaccination in any of the laboratory reproductive outcomes of patients undergoing assisted reproduction treatment: number of follicles (p=0,14), number of oocytes collected (p=0,30), number of mature oocytes (p=0,15), fertilization rate (p=0,14), blastulation rate (p=0,13), good quality embryos (p=0,22).

Conclusion

Our results suggest that the type of vaccine administered do not influence laboratory or embryo development outcomes of patients undergoing assisted reproductive treatments. Our data agrees with current evidence in the literature regarding SARS-CoV-2 vaccine effects on human fertility, although data is still limited, the findings show no relevant difference in the outcomes observed. Previous publish studies already unanimously state that vaccination does not lead to any detrimental effect on the female reproductive physiology as ovarian reserve, ovarian stimulation, folliculogenises, implantation and sustained implantation rates. Few studies had evaluated laboratory outcomes of IVF, and although our data had a small sample size and must be evaluated with caution, our study provided encouraging results showing that the type of SARS-Covid vaccine does not influence in IVF laboratory outcomes and that from a reproductive perspective vaccine should continuously be safely recommended.

Keywords

SARS-CoV-2; embryo development