Effect of female coronavirus disease 2019 vaccination on assisted reproductive outcomes: a systematic review and meta-analysis.

IMPORTANCE: The effect of coronavirus disease 2019 (COVID-19) vaccination on fertility warrants clarification in women undergoing assisted reproductive treatment. OBJECTIVE: To study the association between female COVID-19 vaccination and outcomes of assisted reproductive treatment. DATA SOURCES: PubMed, Embase, the Web of Science, Cochrane Library, and medRxiv and bioRxiv were searched for eligible studies from December 1, 2019, to November 30, 2022, with no language restrictions. STUDY SELECTION AND SYNTHESIS: Observational studies comparing assisted reproductive outcomes between women with and without COVID-19 vaccination were included. The pooled estimates were calculated using the random-effects models as mean differences (MDs), standardized MDs, or odds ratios with 95% confidence intervals (CIs). Heterogeneity was evaluated using the I2 statistic. MAIN OUTCOMES: The number of oocytes retrieved and clinical pregnancy rate. RESULTS: Twenty-one cohort studies involving a total of 19,687 treatment cycles were included. In a comparison of the vaccinated vs. unvaccinated groups, the pooled MD for oocyte number was -0.06 (95% CI, -0.51 to 0.39; I2 = 0), and the pooled odds ratio for clinical pregnancy was 0.95 (95% CI, 0.85-1.05; I2 = 0). Similarly, there were no statistically significant adverse effects identified in other outcomes determined a priori, including 4 cycle characteristics, 6 laboratory parameters, and 3 pregnancy indicators. Most results were consistently unchanged in subgroup and sensitivity analyses, with no evidence of publication bias according to Egger's test. CONCLUSION AND RELEVANCE: Our work did not find significant differences in assisted reproductive outcomes between vaccinated and unvaccinated women. However, more data are warranted to confirm the safety of COVID-19 vaccination for assisted reproductive treatment and in female fertility in general.

Effect of COVID-19 vaccination on semen parameters: A systematic review and meta-analysis.

The aim of this study was to investigate the effect of coronavirus disease 2019 (COVID-19) vaccination on semen parameters through systematic review and meta-analysis. PubMed, EMBASE, Web of Science, and Cochrane Library were comprehensively searched by June 2022. Studies were considered eligible if they compared semen parameters before and after COVID-19 vaccination or between vaccinated and unvaccinated men, with no restrictions on vaccine types or doses. The effect size was calculated as mean difference (MD) with 95% confidence interval (CI) using a random-effects model. Subgroup and sensitivity analyses were conducted to assess the sources of heterogeneity measured by the I2 statistic, with publication bias evaluated by Egger's test. Twelve cohort studies involving 914 participants fulfilled the inclusion criteria. In a comparison of vaccinated versus unvaccinated group, the pooled data revealed no significant differences in semen volume (MD = 0.18 ml, 95% CI -0.02 to 0.38), sperm concentration (MD = 1.16 million/ml, 95% CI -1.34 to 3.66), total sperm motility (MD = -0.14%, 95% CI -2.84 to 2.56), progressive sperm motility (MD = -1.06%, 95% CI -2.88 to 0.77), total sperm count (MD = 5.92 million, 95% CI -10.22 to 22.05), total motile sperm count (MD = 2.18 million, 95% CI -1.28 to 5.63), total progressively motile sperm count (MD = -3.87 million, 95% CI -13.16 to 5.43), and sperm morphology (MD = 0.07%, 95% CI -0.84 to 0.97). The results also remained similar across messenger ribonucleic acid, viral-vector, and inactivated COVID-19 vaccines. Sensitivity analysis identified two individual studies that contributed to heterogeneity, while the effect size was not materially altered. No obvious publication bias was detected among included studies. Our finding suggested that COVID-19 vaccination had no detrimental impact on semen quality, which could be potentially helpful to reduce male vaccine hesitancy and increase vaccination coverage.

Effect of inactivated COVID-19 vaccination on pregnancy outcomes following frozen-thawed embryo transfer: A retrospective cohort study.

OBJECTIVE: To investigate the effect of inactivated coronavirus disease 2019 (COVID-19) vaccination on frozen-thawed embryo transfer (FET) outcomes. METHODS: This retrospective cohort study enrolled 1,210 patients undergoing FET cycles in a single university-affiliated hospital between July 1, 2021, and May 1, 2022. Of them, 387 women with two full doses of inactivated SARS-CoV-2 vaccines (CoronaVac or BBIBP-CorV) after oocyte retrieval were assigned to the vaccinated group, while 823 were unvaccinated as controls. Propensity score matching and multiple regression analysis were applied to control for baseline and cycle characteristics (19 covariates in total). RESULTS: There were 265 patients in each group after matching. The rates of clinical pregnancy (58.5% vs. 60.8%; P = 0.595) and live birth (44.4% vs. 48.8%; P = 0.693) were similar between vaccinated and unvaccinated patients, with adjusted odds ratios of 0.89 (95% confidence interval [CI] 0.61-1.29) and 1.31 (95% CI 0.37-4.56), respectively. Consistently, no significant differences were found in serum human chorionic gonadotropin levels as well as biochemical pregnancy, biochemical pregnancy loss, and embryo implantation rates. Based on the time interval from vaccination to FET, vaccinated patients were further subdivided into two categories of ≤2 months and >2 months, and the outcomes remained comparable. CONCLUSION: Our study showed that inactivated COVID-19 vaccination in women did not have measurable detrimental impact on implantation performance and live birth outcome during FET treatment cycles. This finding denies the impairment of endometrial receptivity and trophoblast function by vaccine-induced antibodies at the clinical level.

Impact of inactivated SARS-CoV-2 vaccination on embryo ploidy: a retrospective cohort study of 133 PGT-A cycles in China.

BACKGROUND: Unsubstantiated concerns have been raised on the potential correlation between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and infertility, leading to vaccine hesitancy in reproductive-aged population. Herein, we aim to evaluate the impact of inactivated SARS-CoV-2 vaccination on embryo ploidy, which is a critical indicator for embryo quality and pregnancy chance. METHODS: This was a retrospective cohort study of 133 patients who underwent preimplantation genetic testing for aneuploidy (PGT-A) cycles with next-generation sequencing technology from June 1st 2021 to March 17th 2022 at a tertiary-care medical center in China. Women fully vaccinated with two doses of Sinopharm or Sinovac inactivated vaccines (n = 66) were compared with unvaccinated women (n = 67). The primary outcome was the euploidy rate per cycle. Multivariate linear and logistic regression analyses were performed to adjust for potential confounders. RESULTS: The euploidy rate was similar between vaccinated and unvaccinated groups (23.2 ± 24.6% vs. 22.6 ± 25.9%, P = 0.768), with an adjusted ß of 0.01 (95% confidence interval [CI]: -0.08-0.10). After frozen-thawed single euploid blastocyst transfer, the two groups were also comparable in clinical pregnancy rate (75.0% vs. 60.0%, P = 0.289), with an adjusted odds ratio of 6.21 (95% CI: 0.76-50.88). No significant associations were observed between vaccination and cycle characteristics or other laboratory and pregnancy outcomes. CONCLUSIONS: Inactivated SARS-CoV-2 vaccination had no detrimental impact on embryo ploidy during in vitro fertilization treatment. Our finding provides further reassurance for vaccinated women who are planning to conceive. Future prospective cohort studies with larger datasets and longer follow-up are needed to confirm the conclusion.

No Effect of Inactivated SARS-CoV-2 Vaccination on in vitro Fertilization Outcomes: A Propensity Score-Matched Study.

PURPOSE: To investigate the impact of inactivated SARS-CoV-2 vaccination on in vitro fertilization (IVF) outcomes. PATIENTS AND METHODS: This retrospective cohort study included 2185 patients undergoing fresh IVF cycles from June 1st to September 13th 2021 in a single university-affiliated hospital. Vaccine administration information was collected and ascertained via immunization records. Patients with two dosages of inactivated SARS-CoV-2 vaccines (Sinopharm or Sinovac) were categorized into the vaccinated group (n = 150), while those unvaccinated were classified as control (n = 2035). Propensity score matching was performed to balance the baseline characteristics (14 covariates) between the two groups at a ratio of 1:4. The main outcome measures were the number of oocytes retrieved, good-quality embryo rate and clinical pregnancy rate. RESULTS: There were 146 women in the vaccinated group and 584 in the control group after matching. The number of oocytes retrieved (9.9 ± 7.1 vs 9.9 ± 6.7; P = 0.893), good-quality embryo rate (33.5 ± 29.8% vs 29.9 ± 28.6%; P = 0.184) and clinical pregnancy rate (59.1% vs 63.6%; P = 0.507) were all similar between the two groups. In addition, no significant differences were observed regarding other cycle characteristics, laboratory parameters and pregnancy outcomes. The results were also comparable when vaccinated patients were subdivided into three categories based on the time interval from complete vaccination to cycle initiation: ≤1 month, >1-2 months, and >2 months. CONCLUSION: Our study provided the first-time evidence that inactivated SARS-CoV-2 vaccination in females did not result in any measurable detrimental effects on IVF treatment. Owing to the present limitations, further prospective studies with larger cohort size and longer follow-up are warranted to validate our conclusion.