Abstract Study question Is SARS-CoV–2 detected by RT-PCR in the reproductive materials and follicular fluid of asymptomatic patients undergoing fertility treatments? Summary answer No SARS-CoV–2 mRNA was detected in sperm, vaginal and follicular fluids samples of asymptomatic patients, irrespective of the nasopharyngeal swab or COVID–19 questionnaire results. What is known already: The COVID–19 pandemic had a huge impact on health care including on fertility clinics. While activities were interrupted during the first wave, ART cycles are currently performed but uncertainties remain regarding the presence of the virus in reproductive materials. The SARS-CoV–2 receptors were detected in reproductive organs but only few studies with limited number of cases reported the presence of SARS-CoV–2mRNA in semen of symptomatic patients. In women, the risk of SARS-CoV–2 contamination in follicular and vaginal fluids remains uncertain. Thus the risk of sexual transmission and the safety of the IVF laboratory procedures are unclear. Study design, size, duration This COVART study is an observational cohort prospective trial conducted at a Belgian academic hospital. Between September 2020 and January 2021, 208 asymptomatic adults patients (men and women) undergoing ART treatments (sperm analysis, IUI, ICSI/ICF cycles, oocyte cryopreservation) were included in the trial after informed consent. All patients followed standard procedures to evaluate COVID–19 risk (nasopharyngeal swab during ovarian stimulation and COVID–19 risk questionnaire). Participants were divided into two groups: COVID–19 positive and negative/unknown groups. Participants/materials, setting, methods: Swabs on the residual reproductive materials were done and stored in viral transport medium at 4 °C until processing. After addition of an internal control in each sample and virus inactivation with Trizol, mRNA was extracted using phenol-chloroform method. Quantitative RT-PCR was performed in duplicate following a previously validated protocol (45 cycles, Roche Light Cycler 480). Negative/positive controls were used to validate each run. The test was considered as positive when CT < 40. Main results and the role of chance A total of 399 samples (126 semen, 162 vaginal fluid, 111 follicular fluid samples) of reproductive residual materials from 208 participants were collected during the peak of the second wave of COVID–19 pandemic, when Belgium was considered as a red zone with a viral Rt of 1.516 and a 14-day COVID–19 cases notification rate above 630 per 100000. Although the policy of the fertility clinic was to cancel all cycles of patients with a positive nasopharyngeal swab test except if specific medical raisons to continue the cycle, 14 samples from 9 non-cancelled patients diagnosed with COVID–19 before or just after the samples collection were analyzed (4 sperm, 5 follicular fluid and 5 vaginal secretion samples). For the 199 remaining patients, the COVID–19 status was negative or unknown. None of the samples were considered as positive after quantitative RT-PCR analysis. Limitations, reasons for caution All the patients were asymptomatic at the time of the samples collection and the large majority was negatively diagnosed for COVID–19 during the ART cycle. The results should be confirmed by including a larger cohort of positive patients. Data on the impact on ART outcomes will be evaluated. Wider implications of the findings: We showed that contaminations of sperm, follicular and vaginal fluids with SARS-CoV–2 are unlikely in asymptomatic patients, even when diagnosed positive, confirming the poor risk of sexual transmission. Moreover, no additional safety measures seems to be implemented in the IVF laboratory to ensure the safety of the staff. Trial registration number P2020/414
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