Previous infection with SARS-CoV-2 impacts embryo morphokinetics but not clinical outcomes in a time-lapse imaging system

Environmental Stress-Induced Alterations in Embryo Developmental Morphokinetics

The association between embryo morphokinetics and its developmental competence is well documented. For instance, early cleaved embryos are more competent in developing to blastocysts, whereas the proportion of abnormally cleaved embryos that further developed to blastocysts is low. Numerous factors, such as the parental age, lifestyle, health, and smoking habits have been reported to affect the embryo morphokinetics and, consequently, its development. However, less is known about the effect of environmental stressors on embryo morphokinetics. The current review discusses the effect of the most concerning environmental stressors on embryo morphokinetics. These stresses include heat stress and human-made chemicals such as phthalates (e.g., bis-(2-ethylhexyl phthalate, dibutyl phthalate, dimethyl phthalate, and their primary metabolites), herbicides (e.g., diaminochlorotriazine, the primary metabolite of atrazine), pharmaceutical compounds (e.g., carbamazepine, nocodazole) and pro-oxidant agents (cumene hydroperoxide, Triton X-100), as well as naturally occurring toxins such as mycotoxin (e.g., aflatoxin B1 and its metabolite, and ochratoxin A). In addition, this review discusses the effect of ionizing or non-ionizing radiation and viral infections (e.g., SARS-CoV-2, papillomavirus). Finally, it points out some potential mechanisms that underlie the impairment of embryo morphokinetics, and it suggests protective compounds, mainly the supplementation of antioxidants to improve the morphokinetics, and consequently, the embryo developmental competence.

The association of post-embryo transfer SARS-CoV-2 infection with early pregnancy outcomes in in vitro fertilization: a prospective cohort study

BACKGROUND

The influence of SARS-CoV-2 infection after embryo transfer on early pregnancy outcomes in in vitro fertilization or intracytoplasmic sperm injection-embryo transfer treatment remains inadequately understood. This knowledge gap endures despite an abundance of studies investigating the repercussions of preceding SARS-CoV-2 infection on early pregnancy outcomes in spontaneous pregnancies.

OBJECTIVE

This study aimed to investigate the association between SARS-CoV-2 infection within 10 weeks after embryo transfer and early pregnancy outcomes in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment.

STUDY DESIGN

This prospective cohort study was conducted at a single public in vitro fertilization center in China. Female patients aged 20 to 39 years, with a body mass index ranging from 18 to 30 kg/m2, undergoing in vitro fertilization/intracytoplasmic sperm injection treatment, were enrolled between September 2022 and December 2022, with follow-up extended until March 2023. The study tracked SARS-CoV-2 infection time (≤14 days, ≤28 days, and ≤10 weeks after embryo transfer), symptoms, vaccination status, the interval between vaccination and embryo transfer, and early pregnancy outcomes, encompassing biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate. The study used single-factor analysis and multivariate logistic regression to examine the association between SARS-CoV-2 infection status, along with other relevant factors, and the early pregnancy outcomes.

RESULTS

A total of 857 female patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment were analyzed. In the first stage, SARS-CoV-2 infection within 14 days after embryo transfer did not have a significant negative association with the biochemical pregnancy rate (adjusted odds ratio, 0.74; 95% confidence interval, 0.51-1.09). In the second stage, SARS-CoV-2 infection within 28 days after embryo transfer had no significant association with the implantation rate (36.6% in infected vs 44.0% in uninfected group; P=.181). No statistically significant association was found with the clinical pregnancy rate after adjusting for confounding factors (adjusted odds ratio, 0.69; 95% confidence interval, 0.56-1.09). In the third stage, SARS-CoV-2 infection within 10 weeks after embryo transfer had no significant association with the early miscarriage rate (adjusted odds ratio, 0.77; 95% confidence interval, 0.35-1.71).

CONCLUSION

Our study suggests that SARS-CoV-2 infection within 10 weeks after embryo transfer may not be negatively associated with the biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. It is important to note that these findings are specific to the target population of in vitro fertilization/intracytoplasmic sperm injection patients aged 20 to 39 years, without previous SARS-CoV-2 infection, and with a body mass index of 18 to 30 kg/m2. This information offers valuable insights, addressing current concerns and providing a clearer understanding of the actual risk associated with SARS-CoV-2 infection after embryo transfer.

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.

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.