Covid-19; Period started 1 wk early on 5/24; This spontaneous case was reported by a consumer and describes the occurrence of MENSTRUATION IRREGULAR (Period started 1 wk early on 5/24) and COVID-19 (Covid-19) in a 32-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination.     Previously administered products included for Product used for unknown indication: Pfizer / BioNTech (Dose Number: 1  Batch/Lot No: ER8729 Location of injection: Arm Left) in April 2021 and Pfizer / BioNTech (Dose Number: 2  Batch/Lot No: EW0173  Location of injection: Arm Left) in May 2021. Past adverse reactions to the above products included No adverse reaction with Pfizer / BioNTech and Pfizer / BioNTech. Concurrent medical conditions included Seasonal allergy and Drug allergy. Concomitant products included ACETAMINOPHEN from 09-May-2022 to 11-May-2022 for an unknown indication.    In December 2021, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 24-May-2022, the patient experienced MENSTRUATION IRREGULAR (Period started 1 wk early on 5/24). On an unknown date, the patient experienced COVID-19 (Covid-19). The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) from 11-May-2022 to 16-May-2022 for COVID-19 treatment, at an unspecified dose and frequency. On 29-May-2022, MENSTRUATION IRREGULAR (Period started 1 wk early on 5/24) had resolved. At the time of the report, COVID-19 (Covid-19) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 09-May-2022, SARS-CoV-2 test: positive (Positive) positive. On 10-May-2022, SARS-CoV-2 test: positive (Positive) positive. On 23-May-2022, SARS-CoV-2 test: negative (Negative) negative. On 29-May-2022, Heart rate: elevated (High) a perception of an elevated heartrate.         The date of birth was reported as Nov-1989. It was reported that treatment medication included antibiotics. It was reported that patient had taken other medications/products within 2 weeks of starting COVID-19 treatment.  Events Nasal congestion, Heart rate irregular, Fatigue, Headache, Lymphadenopathy, and Pyrexia are subsumed under Covid-19 (rebound).   Potential rebound in COVID-19 after recovering with use of Paxlovid: Initial COVID-19 symptoms and positive test on 5/9 and 5/10. Recovered within four days, with last day being congestion only. Remained isolated for 10 days, and felt well enough for a short run and a workout in the second half of that. Patient was mostly at home weekend following isolation, and then developed fever & very swollen lymph node evening of 5/23. Tested negative on home test, but doctor said that it being continued COVID could not be ruled out. Fever & fatigue continued until morning of 5/28, higher than in week of 5/9. Period started 1 wk early on 5/24, and usual menstrual headaches were particularly strong and prolonged. As of 5/29, once again recovered, except for a perception of an elevated heartrate (patient didn't have a baseline to measure against or highly accurate tools to do so)  Device Date : 29May2022.  Company Comment: This spontaneous case concerns a 32-year-old female patient with no medical history reported, who experienced the unexpected non-serious AESI of COVID-19, approximately six months after receiving mRNA-1273 as 3rd dose (date unspecified). The patient was treated with Paxlovid (Nirmatrelvir + Ritonavir) for COVID-19 for five days. Two weeks later the patient experienced rebound Covid-19. The outcome was reported as resolving. Details of clinical course, investigation reports and further treatment were not reported. Approximately 8 months prior to the Moderna dose, the patient had taken two doses of Pfizer / BioNTech COVID-19 vaccine (interchange of vaccine products). The current pandemic situation of COVID-19 could be a confounder. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This spontaneous case concerns a 32-year-old female patient with no medical history reported, who experienced the unexpected non-serious AESI of COVID-19, approximately six months after receiving mRNA-1273 as 3rd dose (date unspecified). The patient was treated with Paxlovid (Nirmatrelvir + Ritonavir) for COVID-19 for five days. Two weeks later the patient experienced rebound Covid-19. The outcome was reported as resolving. Details of clinical course, investigation reports and further treatment were not reported. Approximately 8 months prior to the Moderna dose, the patient had taken two doses of Pfizer / BioNTech COVID-19 vaccine (interchange of vaccine products). The current pandemic situation of COVID-19 could be a confounder. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.