The effect of COVID-19 immunity on frozen-thawed embryo transfer cycles outcome

The impact of coronavirus disease 2019 on frozen-thawed embryo transfer outcomes

Background

Coronavirus disease 2019 (COVID-19) has raised concerns about its potential effects on human fertility, particularly among individuals undergoing assisted reproductive therapy (ART). However, the impact of COVID-19 on female reproductive and assisted reproductive outcomes is unclear. In this study, we aimed to evaluate the effects of COVID-19 on pregnancy outcomes during frozen-thawed embryo transfer (FET) cycles.

Methods

This retrospective cohort study included 327 enrolled patients who underwent FET cycles at a single reproductive centre. The study group consisted of patients treated between 1 January 2023 and 31 March 2023 who recently recovered from COVID-19. The embryos for transfer were generated prior to COVID-19 infection. The control group consisted of patients treated between 1 January 2021 and 31 March 2021 who were not infected and did not receive a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. Demographic and cycle characteristics and outcomes were compared.

Results

A total of 160 recovered women and 167 controls were included. The primary outcome-the live birth rate-was similar between the two groups (43.8% vs. 43.1%, P > 0.05). The secondary outcomes, such as the implantation rates (41.2% vs. 39.3%), biochemical pregnancy rates (56.3% vs. 56.3%), clinical pregnancy rates (52.5% vs. 52.1%), early abortion rates (8.3% vs. 12.6%) and ongoing pregnancy rates (46.9% vs. 44.3%), were also similar (P < 0.05). According to a logistic regression model, the live birth rate did not decrease after SARS-CoV-2 infection after adjusting for confounding factors (adjusted OR (95% CI) = 0.953 (0.597∼1.523)). Regardless of stratification by age or the number of embryos transferred, the differences remained nonsignificant. Subgroup logistic regression demonstrated that the time interval from infection to transplant had no significant influence on the live birth rate.

Conclusions

SARS-CoV-2 infection after oocyte retrieval had no detrimental effect on subsequent FET outcomes.

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 for 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. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Effect of SARS-CoV-2 vaccination on the outcomes of assisted reproductive technology: A review

It has been over 4 years since the coronavirus disease 2019 outbreak, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As an effective response to coronavirus disease 2019, the SARS-CoV-2 vaccines have been widely used around the world. However, couples who are planning to conceive naturally or by assisted reproductive technology (ART) are concerned about the impact of SARS-CoV-2 vaccines on pregnancy and offspring safety. Furthermore, in the initial stage of the epidemic, opinions among physicians and healthcare providers on whether ART patients should be immunized are divided due to the lack of data regarding the impact of the SARS-CoV-2 vaccine on ART. This is not the first, nor will it be the last time humans confront pandemics. It is time to summarize the experience about the effect of the SARS-CoV-2 vaccine on the outcomes of ART, which can provide a reference for the future. This paper reviewed relevant research, and significant adverse effects of the SARS-CoV-2 vaccine on the outcome of ART have not been observed. Considering the increased risk of serious complications in pregnant women infected with SARS-CoV-2, timely vaccination may be a wiser choice.

Assisted Reproductive Technology During COVID-19: A Population-Based Study Of Pregnancy Outcomes

We assessed the impact of the COVID-19 pandemic on the pregnancy outcomes of patients who used assisted reproductive technology. We conducted a population-based cohort study of 443,101 patients who conceived naturally or with assisted reproductive technology between December 2015 and July 2021 and had a delivery in hospitals of Quebec, Canada. The main exposure measure was use of assisted reproductive technology before or during the pandemic. Outcomes included preeclampsia, preterm birth, and other pregnancy complications. We used adjusted log-binomial regression models to estimate risk ratios (RR) and 95% confidence intervals (CI) for the association of assisted reproductive technology with adverse pregnancy outcomes compared with natural conception before vs. during the pandemic. In secondary analyses, we examined the association of COVID-19 infection with pregnancy outcomes among women who used assisted reproductive technology. Compared with natural conception, assisted reproductive technology was associated with an increased risk of preeclampsia (RR 1.43; 95% CI 1.21-1.68), preterm birth (RR 2.07; 95% CI 1.84-2.33), and low birth weight (RR 1.94; 95% CI 1.72-2.20) during the pandemic. However, the same risks were also present before the pandemic. Compared with no infection, COVID-19 infection was not associated with adverse outcomes among women who conceived with assisted reproductive technology. This study suggests that the COVID-19 pandemic did not significantly impact the pregnancy outcomes of women who underwent assisted reproductive procedures in Quebec. The findings are reassuring for patients concerned about the potential reproductive effects of the pandemic.

The type of COVID-19 vaccination does not affect reproductive function and pregnancy outcomes in infertile couples

Introduction

Studies on the effect of vaccine type and two other vaccines other than inactivated vaccines approved in China on in vitro fertilization (IVF) pregnancy outcomes are rare. To complement and confirm the existing findings, this research aimed to investigate whether there are adverse effects of different vaccine types in females and males on reproductive function and clinical pregnancy.

Methods

This retrospective study enrolled 6,455 fresh embryo transfer cycles at the First Affiliated Hospital of Zhengzhou University between May 1, 2021, and October 31, 2022. The primary outcome is the clinical pregnancy rate (CPR). At the same time, the secondary results are the number of oocytes retrieved, two pronuclei (2PN) rate, blastocyst formation rate, high-quality blastocyst rate, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DNA fragment index (DFI) rate).

Results

In the comparison of ovarian stimulation indicators, no statistically significant differences (P > 0.05) were found in Gn days, endometrial thickness, 2PN rate, metaphase 2 (MII) rate, high-quality embryo rate, and blastocyst formation rate. No significant differences (P>0.05) were found in age, body mass index (BMI), education level, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DFI rate) in these four groups. The multivariate regression model showed that neither the types of vaccines nor the vaccination status of both infertile couples significantly affected clinical pregnancy.

Discussion

The type of vaccine does not appear to have an unfavorable effect on ovarian stimulation, embryo development, semen parameters, and clinical pregnancy.

Impact of COVID-19 Vaccination on In Vitro Fertilization Outcomes: A Systematic Review

COVID-19 vaccination, especially vaccines that mimic the structure of the COVID-19 virus (mRNA vaccines), may be wrongly assumed to be disrupting factors affecting in vitro fertilization (IVF) outcome. This study aims to evaluate any significant impact of COVID-19 vaccination in women undergoing IVF to improve vaccine compliance and promote COVID-19 eradication. This was a systematic review study. We searched studies published between 2020 and 2022 using databases such as PubMed, Cochrane, PMC, and CINAHL. Selected studies were carefully analyzed to review the impact of the COVID-19 vaccine on IVF outcomes. Seven retrospective and prospective cohort studies, which involved 3232 female patients undergoing IVF, who also received full doses of COVID-19 vaccinations (mRNA), were included. All studies in the present review showed that despite presenting anti-SARS-CoV-2 antibodies after vaccination, there were no significant differences in IVF outcomes, implantation rates, and pregnancy rates. Contrary to the theory that presumed cross-reactivity between anti- SARS-CoV-2 antibodies and the human syncytin-1 protein could affect syncytiotrophoblast formation and embryo implantation. The present review concluded that COVID-19 vaccination does not result in any detrimental effects on IVF outcomes and is safe for women undergoing IVF treatment. The results of our study are important to tackle misinformation regarding COVID-19 vaccination and infertility that may cause vaccine hesitancy in women of reproductive age.

Effects of SARS-COV-2 infection during the frozen-thawed embryo transfer cycle on embryo implantation and pregnancy outcomes

STUDY QUESTION

Does severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during the frozen-thawed embryo transfer (FET) cycle affect embryo implantation and pregnancy rates?

SUMMARY ANSWER

There is no evidence that SARS-CoV-2 infection of women during the FET cycle negatively affects embryo implantation and pregnancy rates.

WHAT IS KNOWN ALREADY

Coronavirus disease 2019 (COVID-19), as a multi-systemic disease, poses a threat to reproductive health. However, the effects of SARS-CoV-2 infection on embryo implantation and pregnancy following fertility treatments, particularly FET, remain largely unknown.

STUDY DESIGN, SIZE, DURATION

This retrospective cohort study, included women who underwent FET cycles between 1 November 2022 and 31 December 2022 at an academic fertility centre.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women who tested positive for SARS-CoV-2 during their FET cycles were included in the COVID-19 group, while those who tested negative during the same study period were included in the non-COVID-19 group. The primary outcome was ongoing pregnancy rate. Secondary outcomes included rates of implantation, biochemical pregnancy, clinical pregnancy, early pregnancy loss, and ongoing pregnancy. Multivariate logistic regression models were applied to adjust for potential confounders including age, body mass index, gravidity, vaccination status, and endometrial preparation regimen. Subgroup analyses were conducted by time of infection with respect to transfer (prior to transfer, 1-7 days after transfer, or 8-14 days after transfer) and by level of fever (no fever, fever <39°C, or fever ≥39°C).

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 243 and 305 women were included in the COVID-19 and non-COVID-19 group, respectively. The rates of biochemical pregnancy (58.8% vs 62.0%, P = 0.46), clinical pregnancy (53.1% vs 54.4%, P = 0.76), implantation (46.4% vs 46.2%, P = 0.95), early pregnancy loss (24.5% vs 26.5%, P = 0.68), and ongoing pregnancy (44.4% vs 45.6%, P = 0.79) were all comparable between groups with or without infection. Results of logistic regression models, both before and after adjustment, revealed no associations between SARS-CoV-2 infection and rates of biochemical pregnancy, clinical pregnancy, early pregnancy loss, or ongoing pregnancy. Moreover, neither the time of infection with respect to transfer (prior to transfer, 1-7 days after transfer, or 8-14 days after transfer) nor the level of fever (no fever, fever <39°C, or fever ≥39°C) was found to be related to pregnancy rates.

LIMITATIONS, REASONS FOR CAUTION

The retrospective nature of the study is subject to possible selection bias. Additionally, although the sample size was relatively large for the COVID-19 group, the sample sizes for certain subgroups were relatively small and lacked adequate power, so these results should be interpreted with caution.

WIDER IMPLICATIONS OF THE FINDINGS

The study findings suggest that SARS-CoV-2 infection during the FET cycle in females does not affect embryo implantation and pregnancy rates including biochemical pregnancy, clinical pregnancy, early pregnancy loss, and ongoing pregnancy, indicating that cycle cancellation due to SARS-CoV-2 infection may not be necessary. Further studies are warranted to verify these findings.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the National Key Research and Development Program of China (2023YFC2705500, 2019YFA0802604), National Natural Science Foundation of China (82130046, 82101747), Shanghai leading talent program, Innovative research team of high-level local universities in Shanghai (SHSMU-ZLCX20210201, SHSMU-ZLCX20210200, SSMU-ZLCX20180401), Shanghai Jiao Tong University School of Medicine Affiliated Renji Hospital Clinical Research Innovation Cultivation Fund Program (RJPY-DZX-003), Science and Technology Commission of Shanghai Municipality (23Y11901400), Shanghai Sailing Program (21YF1425000), Shanghai's Top Priority Research Center Construction Project (2023ZZ02002), Three-Year Action Plan for Strengthening the Construction of the Public Health System in Shanghai (GWVI-11.1-36), and Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant Support (20161413). The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

COVID-19 Vaccination and Reproductive Health: a Comprehensive Review for Healthcare Providers

With all the current misinformation on social media platforms about the COVID-19 vaccine and its potential effects on fertility, it is essential for healthcare providers to have evidenced-based research to educate their patients, especially those who are trying to conceive, of the risks to mothers and fetuses of being unvaccinated. It is well known that COVID-19 infection puts pregnant women at higher risk of complications, including ICU admission, placentitis, stillbirth, and death. In February of 2021, the American College of Obstetricians and Gynecologists (ACOG), the American Society for Reproductive Medicine (ASRM), and the Society for Maternal-Fetal Medicine (SMFM) released a statement denying any link between COVID vaccination and infertility. ASRM later confirmed and stated that "everyone, including pregnant women and those seeking to become pregnant, should get a COVID-19 vaccine". In this review, we aim to provide a compilation of data that denies any link between vaccination and infertility for healthcare providers to be able to educate their patients based on evidence-based medicine. We also reviewed the effect of COVID-19 virus and vaccination on various parameters and processes that are essential to obtaining a successful pregnancy.

Coronavirus Disease 2019 (COVID-19) Vaccination and Assisted Reproduction Outcomes: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the association between coronavirus disease 2019 (COVID-19) vaccination and female assisted reproduction outcomes through a systematic review and meta-analysis.

DATA SOURCES

We searched Medline (OVID), EMBASE, Web of Science, Cochrane Library, and ClinicalTrials.gov on January 11, 2023, for original articles on assisted reproduction outcomes after COVID-19 vaccination. The primary outcome was rates of clinical pregnancy; secondary outcomes included number of oocytes retrieved, number of mature oocytes retrieved, fertilization rate, implantation rate, ongoing pregnancy rate, and live-birth rate.

METHODS OF STUDY SELECTION

Two reviewers independently screened citations for relevance, extracted pertinent data, and rated study quality. Only peer-reviewed published studies were included.

TABULATION, INTEGRATION, AND RESULTS

Our query retrieved 216 citations, of which 25 were studies with original, relevant data. Nineteen studies reported embryo transfer outcomes, with a total of 4,899 vaccinated and 13,491 unvaccinated patients. Eighteen studies reported data on ovarian stimulation outcomes, with a total of 1,878 vaccinated and 3,174 unvaccinated patients. There were no statistically significant results among our pooled data for any of the primary or secondary outcomes: clinical pregnancy rate (odds ratio [OR] 0.94, 95% CI 0.88-1.01, P =.10), number of oocytes retrieved (mean difference -0.26, 95% CI -0.68 to 0.15, P =.21), number of mature oocytes retrieved (mean difference 0.31, 95% CI -0.14 to 0.75, P =.18), fertilization rate (OR 0.99, 95% CI 0.87-1.11, P =.83), implantation rate (OR 0.92, 95% CI 0.84-1.00, P =.06), ongoing pregnancy rate (OR 0.95, 95% CI 0.86-1.06, P =.40), or live-birth rate (OR 0.95, 95% CI 0.78-1.17, P =.63). A subanalysis based on country of origin and vaccine type was also performed for the primary and secondary outcomes and did not change the study results.

CONCLUSION

Vaccination against COVID-19 is not associated with different fertility outcomes in patients undergoing assisted reproductive technologies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42023400023.

Impact of COVID-19 convalescence on pregnancy outcomes in patients undergoing IVF/ICSI during fresh ART cycles: a retrospective cohort study

Objective

The aim was to study the impact of coronavirus disease 2019 (COVID-19) convalescence on female fertility and laboratory and clinical outcomes in fresh assisted reproductive technology (ART) cycles.

Methods

In this retrospective cohort study, we analyzed data from 294 patients who had recovered from COVID-19 and who underwent fresh ART cycles between January and March 2023 (COVID-19 group). This group was compared with 631 patients who underwent similar ART cycles in the same period in 2022 but without having been infected with COVID-19 (non-COVID-19 group). The analysis focused on comparison of basic demographic characteristics and laboratory parameters of patients in each group. The primary outcome measure was the clinical pregnancy rate, which was examined to assess the impact of COVID-19 infection on the efficacy of ART treatment.

Results

Basal follicle-stimulating hormone (FSH) levels were significantly lower and antral follicle count (AFC) was markedly higher in the COVID-19 group compared to the non-COVID-19 group (P<0.001 and P=0.004, respectively). The predominant ovarian stimulation protocol in the COVID-19 group was GnRH antagonists (64.85%, P<0.001), with a reduced gonadotropin (Gn) dosage and duration in comparison to the non-COVID-19 group (P<0.05). Although the number of blastocysts formed was lower in the COVID-19 group (P=0.017), this group also exhibited a higher blastocyst freezing rate and a higher rate of high-quality embryos per retrieved oocyte (P<0.001 and P=0.023, respectively). Binary logistic regression analysis indicated that COVID-19 convalescence did not significantly impact clinical pregnancy rates in fresh transfer cycles (odds ratio [OR] = 1.16, 95% confidence interval [CI] = 0.68-1.96, P=0.5874). However, smooth curve-fitting and threshold effect analysis revealed an age-related decline in clinical pregnancy rates in both groups, more pronounced in the COVID-19 group, for women aged over 38 years, with the likelihood of clinical pregnancy decreasing by 53% with each additional year of age (odds ratio [OR] = 0.81, 95% confidence interval [CI] = 0.61-1.08, P=0.1460; odds ratio [OR] = 0.47, 95% CI = 0.21-1.05, P=0.0647).

Conclusions

Our findings present no substantial evidence of adverse effects on clinical pregnancy outcomes in fresh ART cycles in patients undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) during the period of convalescence from COVID-19. However, age emerges as a significant factor influencing these outcomes. Notably, for women above 38 years of age, the likelihood of clinical pregnancy in patients with a prior COVID-19 infection decreased by 53% with each additional year. This highlights the importance of considering maternal age, especially in the context of COVID-19, when evaluating the likelihood of successful pregnancy following ART treatments.

Does SARS Cov-2 infection affect the IVF outcome - A systematic review and meta-analysis

STUDY QUESTION

What is the effect of SARS Cov-2 on IVF outcome?

SUMMARY ANSWER

Mild or asymptomatic Covid-19 infection does not appear to affect clinical or ongoing pregnancy rate after IVF.

WHAT IS ALREADY KNOWN

Covid-19 has been shown to affect female and male fertility and reproductive function. Studies have shown variable results regarding impact of Covid-19 on IVF outcome with few reporting impaired ovarian reserve, oocyte and embryo quality, semen parameters, clinical pregnancy rate (CPR) and live birth rate (LBR) while others reported no effect on IVF outcome.

STUDY DESIGN, SIZE, DURATION

An electronic database search of PubMed, EMBASE, SCOPUS, WHO Covid-19 database, Clinical trials.gov and Cochrane Central was performed for articles published in English language between 1st January 2020 and 15th October 2022 by two independent reviewers using predefined eligibility criteria We have included observational studies both prospective and retrospective, cohort studies, and case control studies and excluded narrative reviews, case studies, cost-effectiveness studies or diagnostic studies. Risk of bias was assessed using NOS and quality of evidence was graded by GRADE pro.

PARTICIPANTS, SETTINGS, METHODS

Studies comparing women undergoing IVF and comparing Covid-19 affected with those unaffected by Covid-19 were included. Also, studies comparing immune group (infected or vaccinated) in the study group and unaffected as controls (historical controls, IVF cycles done prior to Covid-19 outbreak but matched with study group) were included. Those with no comparison group or published in language other than English language or duplicate studies were excluded.

MAIN RESULTS AND ROLE OF CHANCE

We identified 5046 records and after full text screening of 82 studies, 12 studies were selected for final review. For the clinical pregnancy rate, there was no difference in the CPR in covid recovered or control patients (OR 0.90, 95 % CI = 0.67 to1.21; I2 = 29 %). Similarly, there was no significant effect on implantation rate (RR 0.92, 95 % CI = 0.68 to1.23; I2 = 31 %) and ongoing pregnancy rate (RR 0.96, 95 % CI = 0.79 to 1.15;I2 = 21 %). The mean number of the oocyte retrieved per patient was not significantly different in both the groups (mean difference 0.52, 95 % CI = -1.45 to 2.49; I2 = 75 %). The certainty of the evidence was low.

LIMITATIONS

The meta-analysis is based on observational studies each involving small number of participants. Few studies reported outcomes as per patient while others reported as per cycle, for uniformity we have reported outcomes as per cycle. Sample size in most of studies was small.

WIDER IMPLICATIONS OF FINDINGS

This systematic review has not shown any significant effect on the outcome of IVF cycles in patients post Covid-19 recovery compared to controls. But given the sample size, the findings should be considered with caution.

REGISTRATION

The review protocol has been registered on PROSPERO (registration number CRD42022314515).

Pregnancy outcomes after frozen-thawed embryo transfer in women with COVID-19 history: A prospective cohort study

The clinical effect of Coronavirus disease 2019 (COVID-19) on endometrial receptivity and embryo implantation remains unclear. Herein, we aim to investigate whether a COVID-19 history adversely affect female pregnancy outcomes after frozen-thawed embryo transfer (FET). This prospective cohort study enrolled 230 women who underwent FET cycles from December 2022 to April 2023 in an academic fertility center. Based on the history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection before FET, women were divided into the infected group (n = 136) and the control group (n = 94). The primary outcome was the clinical pregnancy rate per cycle. Multivariate logistic regression analysis was conducted to adjust for potential confounders, while subgroup analysis and restricted cubic splines were used to depict the effect of postinfection time interval on FET. The results showed that the clinical pregnancy rate was 59.6% in the infected group and 63.9% in the control group (p = 0.513). Similarly, the two groups were comparable in the rates of biochemical pregnancy (69.1% vs. 76.6%; p = 0.214) and embryo implantation (51.7% vs. 54.5%; p = 0.628). After adjustment, the nonsignificant association remained between prior infection and clinical pregnancy (OR = 0.78, 95% CI: 0.42-1.46). However, the odds for clinical pregnancy were significantly lower in the ≤30 days subgroup (OR = 0.15, 95% CI: 0.03-0.77), while no statistical significance was detected for 31-60 days and >60 days subgroups compared with the uninfected women. In conclusion, our findings suggested that SARS-CoV-2 infection in women had no significant effect on subsequent FET treatment overall, but pregnancy rates tended to be decreased if vitrified-thawed embryos were transferred within 30 days after infection. A 1-month postponement should be rationally recommended, while further studies with larger sample groups and longer follow-up periods are warranted for confirmation.

Effects of COVID-19 vaccination on human fertility: a post-pandemic literature review

Although vaccination with the Coronavirus disease 2019 vaccine is important and effective in the prevention of SARS-CoV-2 infection, the public expressed concerns regarding the adverse effects of vaccine on fertility. Some reviews have focused on it, they have been unable to collect sufficient research data because of the earlier publication period. As relevant evidence has gradually increased, we reviewed these studies from the perspectives of males, females with or without pregnancy, and different vaccine types. The results suggest that although males may experience fluctuations in semen parameters within their physiological ranges after receiving the vaccine, it has not yet reached a level of influence on the partner's pregnancy probability. As to female without pregnancy, it is believed that vaccination will not affect fertility; however, more research is needed to explore the short-term impact. Vaccination during any trimester is considered safe in pregnant women.

Pregnancy outcomes following natural conception and assisted reproduction treatment in women who received COVID-19 vaccination prior to conception: a population-based cohort study in China

Introduction

The coronavirus disease-2019 (COVID-19) pandemic has swept across the world and continues to exert serious adverse effects on vulnerable populations, including pregnant women and neonates. The vaccines available at present were designed to prevent infection from COVID-19 strains and control viral spread. Although the incidence of pregnancy cycle outcomes are not likely to increase patients vaccinated prior to pregnancy compared with unvaccinated patients based on our knowledge of vaccination safety, there is no specific evidence to support this hypothesis. Therefore, the current study aimed to investigate the association between maternal vaccination prior to conception and pregnancy outcomes.

Methods

We retrospectively analyzed 2,614 women who received prenatal care and delivered in the Obstetrical Department of The First Affiliated Hospital of Anhui Medical University between February 2022 and November 2022. Of the 1,380 eligible pregnant women, 899 women who had received preconception vaccination were assigned to a vaccine group and 481 women who were not vaccinated were control group. Of the enrolled patients, 291 women received fertility treatment (141 vaccinated women, 150 unvaccinated women). The primary outcomes were pregnancy complications (hypothyroidism, gestational diabetes mellitus, pregnancy-induced hypertension, polyhydramnios, oligohydramnios, premature rupture of membranes and postpartum hemorrhage), obstetric outcomes (preterm birth rate, cesarean section rate) and neonatal outcomes (birth-weight, body length, low-birth-weight rate, rate of congenital defects, neonatal mortality and admission to the neonatal intensive care unit).

Results

There was no significant difference in the incidence of complications during pregnancy and delivery when compared between the vaccine group and control group in either univariate- or multivariate-models. The type of vaccine was not associated with the odds of adverse pregnancy outcome. Among the women with infertility treatment, the vaccinated group and the unvaccinated group had similar pregnancy outcomes.

Conclusion

Women who received COVID-19 vaccination prior to conception had similar maternal and neonatal outcomes as women who were unvaccinated. Our findings indicate that COVID-19 vaccinations can be safely administered prior to pregnancy in women who are planning pregnancy or assisted reproductive treatment. During new waves of COVID-19 infection, women who are planning pregnancy should be vaccinated as soon as possible to avoid subsequent infections.

Impact of SARS-CoV-2 infection on clinical outcomes of in vitro fertilization treatments: a systematic review and meta-analysis

The influence of SARS-CoV-2 infection on clinical outcomes in patients undergoing in vitro fertilization has been uncertain. Therefore, this systematic review and meta-analysis aimed to evaluate the impact of past SARS-CoV-2 infection on IVF outcomes. A comprehensive search of PubMed, EMBASE, and Cochrane Library databases was conducted from December 2019 to January 2023. Included studies comparing IVF outcomes between patients with prior SARS-CoV-2 infection and controls without previous infection were analyzed. Study quality was assessed using the Newcastle-Ottawa Quality Assessment Scale. Sensitivity analysis, publication bias, and heterogeneity were also examined. The review protocol was registered with PROSPERO (CRD42023392007). A total of eight studies, involving 317 patients with past SARS-CoV-2 infection and 904 controls, met the inclusion criteria. The meta-analysis revealed no significant differences between the infection group and controls in terms of clinical pregnancy rate (OR 0.97, 95% CI 0.73-1.29; P = 0.82), implantation rate (OR 0.99, 95% CI 0.67-1.46; P = 0.96), or miscarriage rate (OR 0.64, 95% CI 0.15-2.65; P = 0.53). Subgroup analyses based on transfer type demonstrated comparable clinical pregnancy rates between the two groups in both fresh embryo transfer (OR 0.97, 95% CI 0.69-1.36; P = 0.86) and frozen embryo transfer (OR 0.96, 95% CI 0.38-2.44; P = 0.94). In conclusion, this meta-analysis suggests that previous SARS-CoV-2 infection does not have a detrimental impact on clinical outcomes in IVF patients. These findings provide valuable insights into assessing the influence of prior SARS-CoV-2 infection on successful pregnancy outcomes in IVF treatment. The systematic review was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This review was prospectively registered with the International Prospective Register of Systematic Reviews (ID CRD42023392007) on January 16, 2023.

Effect of prior female SARS-CoV-2 infection on IVF outcomes: a prospective cohort study

Introduction

The clinical impact of SARS-CoV-2 infection on human reproduction remains controversial. This prospective cohort study aimed to assess the effect of prior female SARS-CoV-2 infection on subsequent in vitro fertilization (IVF) outcomes.

Materials and methods

A total of 451 women who underwent fresh IVF treatment between December 1, 2022 and April 30, 2023 were included from an academic fertility center. Participants were divided into the infected group if they had a prior COVID-19 history before cycle initiation (n = 252), while the control group were those uninfected (n = 199). The primary outcomes were the number of oocytes retrieved and clinical pregnancy rate after fresh embryo transfer. Multivariate linear and logistic regression analyses were conducted to control for potential confounders.

Results

The number of oocytes retrieved (11.4 ± 8.3 vs. 11.6 ± 7.7; P = 0.457) and clinical pregnancy rate (70.3% vs. 73.7%; P = 0.590) were similar between infected and uninfected groups, with a fully adjusted β coefficient of 0 (95% confidence interval [CI]: -0.14-0.13) and odds ratio of 0.64 (95% CI: 0.20-2.07), respectively. Consistently, the two groups were comparable in cycle characteristics as well as other laboratory and pregnancy parameters. In both subgroup analyses and restricted cubic splines, different post-infection time intervals to IVF cycle initiation showed no significant associations with treatment outcomes.

Conclusion

Prior SARS-CoV-2 infection in females had no adverse influence on subsequent IVF treatment, regardless of the time interval following infection. Our findings provide reassurance for infected women planning for assisted reproduction. Additional prospective cohort studies with larger datasets and longer follow-up are required to confirm the conclusion.

Comprehensive evaluation of the effect of inactivated SARS-CoV-2 vaccination on female fertility: A retrospective cohort study

Fear of possible negative effects of coronavirus disease 2019 (COVID-19) vaccine on fertility is the main reason for vaccine hesitancy among the public especially women of childbearing age. Despite the high coverage of COVID-19 vaccination in China, more scientific evidence is still needed to address their concerns and guide fertility counseling and management in the future. Herein, we performed a retrospective cohort study at a single large center for reproductive medicine in China between August 2020 and May 2023. Patients aged 20-42 years with no history of laboratory-confirmed COVID-19 were included and categorized into different groups according to their vaccination status. The serum sex hormone levels, anti-Müllerian hormone concentrations, embryo quality, and pregnancy outcomes were evaluated and compared among them. We found there were no significant differences in the concentrations of follicle-stimulating hormone, luteinizing hormone and progesterone between the unvaccinated, first-dose, second-dose, and booster vaccinated groups. However, the estradiol showed a highly significant increase in the one-dose vaccinated group compared with its levels in other groups. Among unvaccinated and either vaccinated patients, anti-Müllerian hormone levels were comparable (p = 0.139). The number of oocytes retrieved, fertilization rate and good-quality embryo rate were all similar between each group of in vitro fertilization and intracytoplasmic sperm injection. No significant differences were observed regarding other laboratory parameters. Moreover, the vaccination status of infertile couples did not exert any adverse effect on the pregnancy outcomes in all assisted reproductive technologies cycles. In short, we comprehensively evaluated the reproductive safety of inactivated severe acute respiratory syndrome coronavirus 2 vaccine and found any dose of vaccination wouldn't negatively affect female fertility parameters such as sex hormone levels and ovarian reserve. Moreover, this is the first study to complete the live birth follow-up of the cohort after receiving inactivated severe acute respiratory syndrome coronavirus 2 vaccine, further dispelling the misconception and providing reassurance for decision-making by clinicians.

Impacts of the COVID-19 pandemic on Chinese assisted reproductive technology institutions and human sperm banks: reflections in the post-pandemic era

OBJECTIVE

The COVID-19 pandemic has been the most serious public health emergency encountered in modern assisted reproductive technology (ART) development. In order to identify lessons learned, this study reviews the effect of the pandemic on ART institutions and human sperm banks in China, and summarizes the experiences and reflections of Chinese scholars post-pandemic era.

METHODS

This review is based on multiple consensus statements on the COVID-19 pandemic issued by Chinese experts as well as current national regulations and principles in ART institutions and human sperm banks to document the current situation of ART services in China, describe the impact of the pandemic on these services, and offer Chinese reflections on worrying issues in the post-pandemic era.

RESULTS

China reached one million ART cycles in 2016, and there are currently 540 ART medical institutions and 27 human sperm banks, with 540 licensed for AIH, 91 for AID, 415 for conventional IVF and ICSI and 85 for PGT. Of these, only 4 institutions carry out 10,000 cycles or more annually, and the proportion of institutions with less than 1,000 cycles has reached 66%, which means that a considerable number of ART institutions are still not saturated. As a consequence of the COVID-19 pandemic, 63.6% of ART providers and 95.5% of human sperm banks suspended operations. By the end of May 2020, China, as an early country affected by the pandemic achieved a national resumption rate of ART medical services of 99.2% and that of human sperm banks of 100.0%. Reports from the first and largest human sperm bank in China showed that qualification, semen concentration and sperm viability rates measured at primary screening have significantly decreased post-pandemic. Much like in other countries, Chinese experts developed a consensus on prevention and control measures during the pandemic. In principle, all ART activities should be suspended during acute phases of infection spread. Chinese scholars highlight that attention should be paid to young patients with fertility requirements during and after COVID-19, and emphasize the importance of fertility evaluation and clinical intervention. In addition, couples should be reminded that during ART treatment, disinfectants should not be used excessively to minimize risks of damaging the reproductive system, gametes and zygotes. At the same time, timely and reasonable guidance for tackling negative emotions from stress response is needed to provide reassurance and to avoid irrational fear and excessive stress. Seminal parameters should be re-examined 2 months after SARS-CoV-2 vaccination, and ART treatments recommenced if no abnormalities are detected.

CONCLUSIONS

Given the growing frequency of outbreaks of global infectious diseases in recent years, ART institutions and human sperm banks should pay attention to improving their prevention and control capabilities. To a certain extent, decisions and measures adopted in China during COVID-19 pandemic are worthy of recognition and acceptance. Chinese scholars have discussed, proactively responded to and understand the key issues surrounding ART development during the pandemic with the aim of contributing to the substantial progress and healthy development of ART services in the world.

Effects of the Severe Acute Respiratory Syndrome Coronavirus 2 Inactivated Vaccine on the Outcome of Frozen Embryo Transfers: A Large Scale Clinical Study

Background

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a life-threatening infectious disease that has become a global pandemic.

Objective

This study aimed to explore the effects of SARS-CoV-2 inactivated vaccine on the outcome of frozen embryo transfer (FET).

Methods

We grouped patients who underwent FET between August 2021 and March 2022 based on their vaccination status, number of doses, and the interval between the last dose and the FET, and then compared the differences in pregnancy outcomes among the groups.

Results

There were 1084 vaccinated patients and 1228 non-vaccinated ones. There were significant differences in the live birth rate between the vaccination and non-vaccination groups (16.61% vs 28.26%), among the one-dose, two-dose, and three-dose groups (22.28% vs 19.51% vs 7.27%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (38.38% vs 27.27% vs 12.03%). There were significant differences in the persistent pregnancy rate between the vaccination and non-vaccination groups (22.88% vs 14.09%), among the one-dose, two-dose, and three-dose groups (14.51% vs 23.80% vs 38.18%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (1.01% vs 8.44% vs 28.16%). There were significant differences in the neonatal weight between the vaccination and non-vaccination groups [3805.50 (3746.00-3863.50) vs 2970.00 (2500.00-3400.00)]. There were significant differences in the premature birth rate among the one-dose, two-dose, and three-dose groups (23.26% vs 34.59% vs 100.00%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (15.79% vs 21.43% vs 37.00%).

Conclusion

Pregnancy outcomes were not affected by taking the SARS-CoV-2 inactivated vaccine before FET, the number of doses, and the interval between doses. These findings provide evidence supporting the safety of administering the SARS-CoV-2 inactivated vaccine during pregnancy, which can be used as a guide for vaccinating patients undergoing ART.

COVID-19 Vaccines and Assisted Reproductive Techniques: A Systematic Review

Objective: To review the current knowledge concerning COVID-19 vaccination and assisted reproductive techniques (ART). Methods: A systematic review in Pubmed-Medline, the Cochrane Database, the Web of Science, and the National Guideline was performed. Studies were selected if they were primary studies, included vaccinated (case) and unvaccinated (control) patients, and described fertility treatment response. Results: A total of 24 studies were selected. Outcomes related to the association between COVID-19 vaccination and ART were collected. The vast majority of studies found no statistical differences concerning oocyte stimulation response, embryo quality, implantation rates, or pregnancy outcome (clinical or biochemical pregnancy rates and losses) when comparing cases and controls. Similarly, no differences were found when comparing different types of vaccines or distinct ART (artificial insemination, in vitro fertilization, and embryo transfer of frozen embryos). Conclusions: Patients receiving ART and health care professionals should be encouraged to complete and recommend COVID-19 vaccination, as the available evidence regarding assisted reproductive outcomes is reassuring.

COVID-19 infection after oocyte retrieval did not have detrimental effects on embryo implantation for frozen embryo transfer

Patients preparing for their renewal fertility treatments with embryos frozen before coronavirus disease 2019 (COVID-19) infection do not need to be concerned about the potential impact of COVID-19 infection on oocyte quality and embryonic development. However, many women are still hesitant to undergo frozen embryo transfer (FET) due to fear of the detrimental effect of COVID-19 infection on endometrial receptivity and embryo implantation. The objective was to explore whether COVID-19 infection after oocyte retrieval is related to an increased risk of adverse pregnancy outcomes in a cohort of Chinese women undergoing FET. A retrospective cohort study was conducted among 300 infertile women undergoing FET with embryos frozen before COVID-19 infection. Women were categorized into noninfection, infection before FET, or infection after FET groups. Multivariable logistic regression was performed to assess the association of COVID-19 infection with clinical pregnancy outcomes, including biochemical pregnancy, clinical pregnancy, and early miscarriage. The implantation rates for patients in the group with infection before FET (29.14%) and the group with infection after FET (30.38%) were not significantly lower than those in the noninfection group (31.03%). The rate of biochemical pregnancy (54.55% vs. 52.27%, p = 0.750; 43.14% vs. 52.27%, p = 0.209) was not significantly different among the three groups. Although the clinical pregnancy rate showed a declining trend from 45.45% in the noninfection group to 38.27% in the group with infection after FET, this result was not statistically significant. The early miscarriage rate was similar in the group with infection before FET and the group with infection after FET compared with that in the noninfection group (3.64% vs. 5.68%, p = 0.496; 6.86% vs. 5.68%, p = 0.739). After adjusting for potential confounders, the biochemical pregnancy rate, clinical pregnancy rate, and early miscarriage rate were not significantly different for patients with infection before or after FET compared with patients without infection. This research indicated that COVID-19 infection after oocyte retrieval with embryos frozen before infection did not cause any detrimental effect on endometrial receptivity for embryo implantation.

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 the outcome of in vitro fertilization: A systematic review and meta-analysis

Background

Universal COVID-19 vaccination programs are now recommended in several countries and represent the most effective preventive measure against COVID-19. However, some reports suggest that vaccination may cause infertility or have adverse effects on pregnancy. Conflicting reports have led to vaccine hesitancy in women planning pregnancy.

Purpose

To determine whether vaccination against COVID-19 affects in vitro fertilization (IVF) outcomes, we conducted a meta-analysis.

Method

A systematic search was conducted using PubMed, Embase, MEDLINE, and Web of Science databases for all published literature on COVID-19 vaccines and outcomes of IVF. International Prospective Register of Systematic Reviews registration was completed on September 13, 2022 (CRD42022359771).

Results

We analyzed 20 studies totaling 18,877 individual cases undergoing IVF. COVID-19 vaccination had significant effect on clinical and ongoing pregnancy rate (risk ratio (RR): 0.97; 95% confidence interval (CI): 0.94–0.99; RR: 0.93; 95% CI: 0.87–0.99). These outcomes did not differ between vaccinated and unvaccinated individuals: biochemical pregnancy rate (RR: 0.95; 95% CI: 0.88–1.03), implantation rate (RR: 1.02; 95%CI: 0.97–1.07; P = 0.41), the number of oocytes (mean difference (MD): 0.12; 95% CI: −0.65–0.88) and MII/mature oocytes recovered (MD: 0.27; 95% CI: −0.36–0.90), blastocysts rate (MD: 0.01; 95% CI: −0.04, 0.06), and fertilization rate (MD: 1.08; 95% CI: −0.57, 2.73).

Conclusion

Our findings suggest that vaccination against COVID-19 does not adversely affect the biochemical pregnancy rates; number of oocytes and MII/mature oocytes obtained; implantation, blastocysts; and fertilization rates in women undergoing IVF treatment. Subgroup analysis showed that the mRNA vaccine had no statistical significance on all indexes (clinical, biochemical, or ongoing pregnancy rates; implantation, blastocysts, or fertilization rates; and the number of oocytes and MII/mature oocytes). The findings of this meta-analysis are anticipated to increase the willingness of women planning IVF treatment to receive COVID-19 vaccination and provide evidence-based medical guidance for the development and implementation of guidelines.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022359771.

SARS-CoV-2, fertility and assisted reproduction

BACKGROUND

In 2020, SARS-CoV-2 and the COVID-19 pandemic had a huge impact on the access to and provision of ART treatments. Gradually, knowledge of the virus and its transmission has become available, allowing ART activities to resume. Still, questions on the impact of the virus on human gametes and fertility remain.

OBJECTIVE AND RATIONALE

This article summarizes published data, aiming to clarify the impact of SARS-CoV-2 and the COVID-19 disease on human fertility and assisted reproduction, as well as the impact of vaccination, and from this, provide answers to questions that are relevant for people contemplating pregnancy and for health care professionals.

SEARCH METHODS

PUBMED/MEDLINE and the WHO COVID-19 database were searched from inception to 5 October 2022 with search terms focusing on 'SARS-CoV-2' and gametes, embryos, reproductive function, fertility and ART. Non-English studies and papers published prior to 2020 were excluded, as well as reviews and non-peer reviewed publications. Full papers were assessed for relevance and quality, where feasible.

OUTCOMES

From the 148 papers included, the following observations were made. The SARS-CoV-2-binding proteins, angiotensin-converting enzyme 2 (ACE2) and type II transmembrane serine protease (TMPRSS2), are expressed in the testis, but co-expression remains to be proven. There is some evidence of SARS-CoV-2 RNA in the ejaculate of COVID-19 patients with severe disease, but not in those with mild/moderate disease. SARS-CoV-2 infection can impair spermatogenesis, but this seems to resolve after one spermatogenic cycle. Testosterone levels seem to be lower during and after COVID-19, but long-term data are lacking; disease severity may be associated with testosterone levels. COVID-19 cannot be considered a sexually transmitted disease. There is no co-expression of ACE2 and TMPRSS2 in the myometrium, uterus, ovaries or fallopian tubes. Oocytes seem to have the receptors and protease machinery to be susceptible to SARS-CoV-2 infection; however, viral RNA in oocytes has not been detected so far. Women contemplating pregnancy following COVID-19 may benefit from screening for thyroid dysfunction. There is a possible (transient) impact of COVID-19 on menstrual patterns. Embryos, and particularly late blastocysts, seem to have the machinery to be susceptible to SARS-CoV-2 infection. Most studies have not reported a significant impact of COVID-19 on ovarian reserve, ovarian function or follicular fluid parameters. Previous asymptomatic or mild SARS-CoV-2 infection in females does not seem to negatively affect laboratory and clinical outcomes of ART. There are no data on the minimum required interval, if any, between COVID-19 recovery and ART. There is no evidence of a negative effect of SARS-CoV-2 vaccination on semen parameters or spermatogenesis, ovarian function, ovarian reserve or folliculogenesis. A transient effect on the menstrual cycle has been documented. Despite concerns, cross reactivity between anti-SARS-CoV-2 spike protein antibodies and Syncytin-1, an essential protein in human implantation, is absent. There is no influence of mRNA SARS-CoV-2 vaccine on patients' performance during their immediate subsequent ART cycle. Pregnancy rates post-vaccination are similar to those in unvaccinated patients.

WIDER IMPLICATIONS

This review highlights existing knowledge on the impact of SARS-CoV-2 infection or COVID-19 on fertility and assisted reproduction, but also identifies gaps and offers suggestions for future research. The knowledge presented should help to provide evidence-based advice for practitioners and couples contemplating pregnancy alike, facilitating informed decision-making in an environment of significant emotional turmoil.

Safety of COVID-19 vaccination in women undergoing IVF/ICSI treatment - Clinical study and systematic review

Background

It was suggested that vaccination in general might affect reproductive health. Safety of COVID-19 vaccination in women undergoing assisted reproductive techniques (ART) treatment is not well established.

Methods

We performed a retrospective study including 536 women undergoing fresh embryo transfer after IVF/ICSI treatment in a huge IVF center in southern China to investigate the effect of COVID-19 vaccination on oocyte maturation, fertilization rate, blastulation rate, implantation rate, clinical pregnancy rate and miscarriage rate. In addition, we performed a systematic review of existing studies on the safety of COVID-19 vaccination in women undergoing ART treatment.

Results

In our study, 268 women received inactivated or recombinant COVID-19 vaccination and 268 controls were enrolled based on propensity score matching. We observed a decreased fertilization rate and signs for impaired oocyte maturation in vaccinated women. Besides our study, there were 15 studies analyzing the safety of COVID-19 vaccination in women undergoing ART treatment. For the mRNA vaccines, no adverse signals were reported concerning oocyte maturation, fertilization rate, blastulation rate, implantation rate, clinical pregnancy rate and miscarriage rate. In women being vaccinated with an inactivated vaccine, implantation rate, clinical pregnancy rate and miscarriage rate were not affected, whereas oocyte maturation and fertilization rate were impaired.

Conclusions

Vaccination against COVID-19 in women undergoing ART treatment seems to be safe especially for women getting mRNA vaccines. The effects on oocyte maturation and fertilization rate of inactivated and recombinant COVID-19 vaccinations might be a safety signal and need further investigation and independent confirmation.

Does mRNA COVID-19 vaccination in oocyte donors impact ovarian stimulation parameters or IVF outcomes for recipients?

RESEARCH QUESTION

What is the effect of mRNA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in young oocyte donors in terms of ovarian response to stimulation, fertilization rate, embryo development and clinical outcomes in recipients?

DESIGN

This retrospective, multicentre cohort study evaluated 115 oocyte donors who had undergone at least two ovarian stimulation protocols (before and after complete SARS-CoV-2 vaccination) between November 2021 and February 2022. Comparisons were made of the primary outcomes of days of stimulation, total dose of gonadotrophins and laboratory performance in ovarian stimulation in oocyte donors before and after vaccination. A total of 136 cycles in matched recipients were analysed as secondary outcomes and, from those, 110 women received a fresh single-embryo transfer, with analysis of biochemical β-human chorionic gonadotrophin concentrations and rates of clinical pregnancy with heartbeat.

RESULTS

Longer stimulation was required in the post-vaccination than pre-vaccination group (10.31 ± 1.5 versus 9.51 ± 1.5 days; P < 0.001) along with higher gonadotrophin consumption (2453.5 ± 740 versus 2235.5 ± 615 IU; P < 0.001) with a similar starting dose of gonadotrophins in both groups. More oocytes were retrieved in the post-vaccination group (16.62 ± 7.1 versus 15.38 ± 7.0; P = 0.02). However, the number of metaphase II (MII) oocytes was similar between groups (pre-vaccination 12.61 ± 5.9 versus post-vaccination 13.01 ± 6.6; P = 0.39) and the ratio of MII/retrieved oocytes favoured the pre-vaccination group (0.83 ± 0.1 versus 0.77 ± 0.2 post-vaccination; P = 0.019). In recipients with a similar number of provided oocytes, the fertilization rate, total number of obtained blastocysts, number of top-quality blastocysts, and rates of biochemical pregnancy and clinical pregnancy with heartbeat were not significantly different between groups.

CONCLUSIONS

This study shows no adverse influence of mRNA SARS-CoV-2 vaccination on ovarian response in a young population.

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.

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.

Association Between COVID-19 Vaccination and Artificial Insemination Outcomes for Couples Experiencing Infertility

This cohort study investigates the association between COVID-19 vaccination status and artificial insemination by partner outcomes among couples experiencing infertility in China.

Inactivated Covid-19 vaccine did not undermine live birth and neonatal outcomes of women with frozen-thawed embryo transfer

STUDY QUESTION

Does inoculation with inactivated vaccines against coronavirus disease 2019 (Covid-19) before frozen-thawed embryo transfer (FET) affect live birth and neonatal outcomes?

SUMMARY ANSWER

Inactivated Covid-19 vaccines did not undermine live birth and neonatal outcomes of women planning for FET.

WHAT IS KNOWN ALREADY

Accumulating reports are now available indicating the safe use of mRNA vaccines against Covid-19 in pregnant and lactating women, and a few reports indicate that they are not associated with adverse effects on ovarian stimulation or early pregnancy outcomes following IVF. Evidence about the safety of inactivated Covid-19 vaccines is very limited.

STUDY DESIGN, SIZE, DURATION

This is a retrospective cohort analysis from Reproductive Medical Center of a tertiary teaching hospital. Clinical records and vaccination record of 2574 couples with embryos transferred between 1 March 2021 and 30 September 2021 were screened for eligibility of this study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Clinical and vaccination data of infertile couples planning for FET were screened for eligibility of the study. The reproductive and neonatal outcomes of FET women inoculated with inactivated Covid-19 vaccines or not were compared. The primary outcomes were live birth rate per embryo transfer cycle and newborns' birth height and weight. Secondary outcomes included rates of ongoing pregnancy, clinical pregnancy, biochemical pregnancy and spontaneous miscarriage. Multivariate logistical regression and propensity score matching (PSM) analyses were performed to minimize the influence of confounding factors. Subgroup analyses, including single dose versus double dose of the vaccines and the time intervals between the first vaccination and embryo transfer, were also performed.

MAIN RESULTS AND THE ROLE OF CHANCE

Vaccinated women have comparable live birth rates (43.6% versus 45.0% before PSM, P = 0.590; and 42.9% versus 43.9% after PSM, P = 0.688), ongoing pregnancy rates (48.2% versus 48.1% before PSM, P = 0.980; and 52.2% versus 52.7% after PSM, P = 0.875) and clinical pregnancy rate (55.0% versus 54.8% before PSM, P = 0.928; and 54.7% versus 54.2% after PSM, P = 0.868) when compared with unvaccinated counterparts. The newborns' birth length (50.0 ± 1.6 versus 49.0 ± 2.9 cm before PSM, P = 0.116; and 49.9 ± 1.7 versus 49.3 ± 2.6 cm after PSM, P = 0.141) and birth weight (3111.2 ± 349.9 versus 3030.3 ± 588.5 g before PSM, P = 0.544; and 3053.8 ± 372.5 versus 3039.2 ± 496.8 g after PSM, P = 0.347) were all similar between the two groups. Neither single dose nor double dose of vaccines, as well as different intervals between vaccination and embryo transfer showed any significant impacts on reproductive and neonatal outcomes.

LIMITATIONS, REASONS FOR CAUTION

The main findings might be limited by retrospective design. Besides, inoculations of triple dose of Covid-19 vaccines were not available by the time of data collection, thus the results cannot reflect the safe use of triple dose of inactivated Covid-19 vaccines. Finally, history of Covid-19 infection was based on patients' self-report rather than objective laboratory tests.

WIDER IMPLICATIONS OF THE FINDINGS

Eligible individuals of inactivated vaccines against Covid-19 should not postpone vaccination plan because of their embryo transfer schedule, or vice versa.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Medical Key Discipline of Guangzhou (2021-2023). All authors had nothing to disclose.

TRIAL REGISTRATION NUMBER

N/A.

The impact of COVID-19 vaccines on fertility-A systematic review and meta-analysis

BACKGROUND

Despite literature's evidence about COVID-19 vaccines' safety, concerns have arisen regarding adverse events, including the possible impact on fertility, accentuated by misinformation and anti-vaccine campaigns. The present study aims to answer the question: Is there any impact of COVID-19 vaccines on the fertility of men and women of reproductive age?

METHODS

PubMed, Scopus, Web of Science, Cochrane and Embase databases were searched for eligible studies until June 8th, 2022. The search was restricted to articles regarding humans, published in any languages, without additional restrictions. Studies' quality was assessed by the Newcastle-Ottawa and the Before and After Quality Assessment scales for cohort and pre-post studies, respectively. Random-effect meta-analyses were performed for parameters considered in ≥ 2 studies, calculating means, p-values and 95 % Confidence Intervals (CIs).

RESULTS

Out of 1406 studies screened, 29 were included in the systematic review. These studies, conducted in Israel (34.5 %), USA (24.1 %), Russia (20.7 %) China (10.3 %), Italy (3.5 %), North America (3.5%) and Turkey (3.5 %) were of poor (34.5 %), moderate (58.6 %) and good (6.9 %) quality. Meta-analyses were performed for pre- and post-vaccination sperm progressive motility (44 %, 95 % CI 42 %-62 % vs 43 %, 95 % CI 31 %-59 % p = 0.07) and concentration (50.6 mln/ml, 95 % CI 35.1-72.8 vs 55.4 mln/ml, 95 % CI 37.4-82.2p = 0.12). Biochemical (0.51, 95 % CI 0.40-0.66 vs 0.60, 95 % CI 0.53-0.68p = 0.45) and clinical (0.45, 95 % CI 0.37-0.54 vs 0.47, 95 % CI 0.40-0.55 p = 0.31) pregnancy rate did not differ among vaccinated and not vaccinated groups. Subgroup meta-analyses based on the type of vaccine showed no significant difference: between vaccinated with mRNA vaccines and non-vaccinated regarding biochemical pregnancy rates; pre- and post-vaccination with Gam-COVID-Vac regarding testosterone, FSH and LH levels; pre- and post-vaccination with BNT162b2 vaccines regarding sperm volumes.

CONCLUSION

Based on the studies published so far, there is no scientific proof of any association between COVID-19 vaccines and fertility impairment in men or women.

Association Between Time Interval from COVID-19 Vaccination to In Vitro Fertilization and Pregnancy Rate After Fresh Embryo Transfer

IMPORTANCE

There is a lack of information regarding the need to postpone conception after COVID-19 vaccination.

OBJECTIVE

To investigate the time interval between the first dose of inactivated COVID-19 vaccine and in vitro fertilization (IVF) treatment as well as the rate of pregnancy after a fresh embryo transfer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted at a single public IVF center in China. Female patients aged 20 to 47 years and undergoing IVF treatment were consecutively registered from May 1 to December 22, 2021, with follow-up until March 31, 2022. Patients with SARS-CoV-2 infection before or during IVF treatment and those who underwent 2 or more IVF treatments, received the noninactivated or unknown COVID-19 vaccine, or did not have a fresh embryo transfer were excluded from this study.

EXPOSURES

The vaccinated group (subdivided into 4 subgroups of time interval from first vaccination to fertilization treatment: ≤30 days, 31-60 days, 61-90 days, and ≥91 days) and nonvaccinated group.

MAIN OUTCOMES AND MEASURES

Risk ratios (RRs) for the association between the time interval and ongoing pregnancy (pregnancy continued at least 12 weeks).

RESULTS

A total of 3052 female patients (mean [SD] age, 31.45 [3.96] years) undergoing IVF treatment were analyzed in this study. There were 667 vaccinated patients receiving IVF (35 were vaccinated ≤30 days, 58 were vaccinated 31-60 days, 105 were vaccinated 61-90 days, and 469 were vaccinated ≥91 days before fertilization treatment), and 2385 unvaccinated patients receiving treatment. The ovarian stimulation and laboratory parameters were similar among all groups. Ongoing pregnancy was significantly lower in the 30 days or less subgroup (34.3% [12 of 35]; adjusted RR [aRR], 0.61; 95% CI, 0.33-0.91) and the 31 to 60 days' subgroup (36.2% [21 of 58]; aRR, 0.63; 95% CI, 0.42-0.85). A slightly but not statistically lower rate was found in the 61 to 90 days' subgroup, and no reduced risk for ongoing pregnancy in the 91 days or more subgroup was observed (56.3% [264 of 469]; aRR, 0.96; 95% CI, 0.88-1.04) compared with the unvaccinated group (60.3% [1439 of 2385], as reference).

CONCLUSIONS AND RELEVANCE

Findings of this study suggest that receipt of the first inactivated COVID-19 vaccine dose 60 days or less before fertilization treatment is associated with a reduced rate of pregnancy. In patients undergoing IVF treatment with a fresh embryo transfer, the procedure may need to be delayed until at least 61 days after COVID-19 vaccination.

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 β 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.

Effects of COVID-19 vaccination status, vaccine type, and vaccination interval on IVF pregnancy outcomes in infertile couples

Purpose

This study aimed to explore whether the coronavirus disease (COVID-19) vaccination of both partners in infertile couples, different types of COVID-19 vaccines, and the interval between complete vaccination and oocyte retrieval or embryo transfer (ET) affect the quality of embryos and pregnancy rates in in vitro fertilization (IVF).

Methods

This was a prospective cohort study, comprising 735 infertile couples conducted between December 6, 2021, and March 31, 2022, in a single university hospital-based IVF center. The patients were divided into different groups according to the vaccination status of both partners in infertile couples, type of vaccine, and interval between complete vaccination and IVF treatment. The embryo quality and pregnancy rates were compared among different groups.

Results

The results showed that embryo quality and pregnancy rates had no significant differences among different groups. The multivariate regression model showed that the vaccination status of both infertile couples, types of vaccines, and intervals had no significant effects on the clinical pregnancy rate.

Conclusions

The vaccination status of both partners in infertile couples, different types of vaccines, and time intervals have no effect on embryo quality and pregnancy rates in IVF. This is the first study to compare the vaccination status of both partners in infertile couples and the impact of different vaccine types on pregnancy rates and embryo quality in detail. Our findings provide evidence of vaccine safety for infertile couples wishing to undergo IVF treatment. This evidence is crucial for decision-making by clinicians and policymakers involved in IVF cycles.

The impact of COVID-19 on A fertility center in Indonesia: A brief report

The coronavirus disease 2019 (COVID-19) affected the delivery of care in the fertility center. The higher transmissibility feature of omricon variant increase the transmission possibility between patients, healthcare professionals, and staff. Herein, we report the impact of the COVID-19 pandemic to the fertility center in Indonesia during the third wave period of the pandemic. Seven in vitro fertilization (IVF) cases were cancelled because the patients were tested positive for COVID-19 during their IVF program. Six of the total seventeen medical staff in our center were also tested positive for COVID-19 and stayed at home for self isolation. The cancellation of the IVF program was due to the lack of data regarding safety of IVF procedure in COVID-19 patients, shortage of medical staff, and the lack of negative pressure room in our fertility center. Our priority is to protect the remaining healthy patients in our center as well as the medical staff. The COVID-19 disadvantage both patients, care provider in reproductive healthcare. Regular screening of COVID-19 in fertility setting is highly recommended.

SARS-CoV-2 mRNA vaccination (BNT162b2) has no adverse effect on elective oocyte cryopreservation outcomes

Research question

Do elective oocyte cryopreservation outcomes in women 1–13 months after SARS-CoV-2 vaccination alter compared with unvaccinated women and do different time intervals between vaccination and ovarian stimulation impact these outcomes?

Design

This retrospective cohort study, conducted in a university-affiliated IVF centre, included 232 elective oocyte cryopreservation cycles of vaccinated and unvaccinated patients, without previous infection with the SARS-CoV-2 virus, between December 2020 and January 2022. Two control groups – pre-pandemic (January 2019 to February 2020) and intra-pandemic (December 2020 to January 2022) unvaccinated groups – were compared with the vaccinated group, further divided into four subgroups (under 3, 3–6, 6–9 and 9–13 months). The primary outcome was the elective oocyte cryopreservation cycle outcomes – number of retrieved and number of mature oocytes.

Results

The vaccinated group demonstrated comparable outcomes with regards to number of retrieved and mature oocytes compared with the pre-pandemic and intra-pandemic unvaccinated groups (12.6 ± 8.0 versus 13.0 ± 8.2 and 12.5 ± 7.4 retrieved and 10.1 ± 6.9 versus 9.5 ± 6.4 and 10.1 ± 6.3 mature oocytes, respectively; not significant for both). Similar results were noted in a comparison between the intra-pandemic unvaccinated group and the four vaccinated subgroups. No correlation was found between the parameter of days from vaccination and cycle outcomes. Similarly, analysis of covariance showed no association between vaccination status and timing and number of mature oocytes.

Conclusions

The SARS-CoV-2 vaccination does not alter the outcomes of elective oocyte cryopreservation procedures. This is true even in a relatively long time interval of 9 to 13 months from vaccination.

The impact of past COVID-19 infection on pregnancy rates in frozen embryo transfer cycles

PURPOSE

To study the effect of SARS-CoV-2 infection on pregnancy rates in frozen embryo transfer (FET) cycles.

METHODS

A retrospective cohort study including women under the age of 42 with documented SARS-CoV-2 infection up to 1 year prior to treatment, undergoing FET cycles in the first half of 2021, with transfer of embryos generated prior to the infection. Controls were SARS-CoV-2 non-diagnosed, non-vaccinated women matched by age, number, and day of embryo transfer. Demographic and cycle characteristics and outcomes were compared.

RESULTS

Forty-one recovered women and 41 controls were included. Pregnancy rates were 29% and 49% respectively (p = 0.070). Stratification by time from SARS-CoV-2 infection to transfer into ≤ 60 and > 60 days revealed a difference in pregnancy rates, with women in the COVID group having lower pregnancy rates if infected in proximity to the transfer (21% vs. 55%; p = 0.006). In a logistic regression model, infection was a significant variable (p = 0.05, OR 0.325, 95% CI 0.106-0.998). Logistic regression applied on the subgroup of women infected in proximity to the transfer further strengthened the univariate results, with COVID-19 remaining a significant parameter (p = 0.005, OR 0.072, 95% CI 0.012-0.450).

CONCLUSIONS

In FET cycles of patients with past SARS-CoV-2 infection, in which oocytes were retrieved prior to infection, decreased pregnancy rates were observed, specifically in patients who recovered less than 60 days prior to embryo transfer. Pending further studies, in cases of FET cycles with limited number of embryos, postponing embryo transfer for at least 60 days following recovery from COVID-19 might be considered when feasible.