Maternal exposure during pregnancy; Rebound of Symptoms such as congestion, body aches; interchange of vaccine products (2 doses of BioNTech); This spontaneous prospective pregnancy case was reported by a patient and describes the occurrence of COVID-19 (Rebound of Symptoms such as congestion, body aches), MATERNAL EXPOSURE DURING PREGNANCY (Maternal exposure during pregnancy) and INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products (2 doses of BioNTech)) in a 31-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. CILFZIA) for COVID-19 vaccination.     Previously administered products included for Drug use for unknown indication: Pfizer biontech (Dose Number: 1 Batch/Lot No: ER8735 Location of injection: Arm Left) on 20-Apr-2021 and Pfizer biontech (Dose Number: 2 Batch/Lot No: EW0173 Location of injection: Arm Left) on 11-May-2021. Past adverse reactions to the above products included No adverse event with Pfizer biontech and Pfizer biontech. Concurrent medical conditions included Drug allergy. Concomitant products included MINERALS NOS, VITAMINS NOS (PRENATAL VITAMINS [MINERALS NOS;VITAMINS NOS]) from 01-Sep-2021 to an unknown date, CALCIUM from 01-Sep-2021 to an unknown date, IRON from 01-Mar-2022 to an unknown date and ACETYLSALICYLIC ACID (ASPIRIN 81) from 16-May-2022 to an unknown date for an unknown indication.    On 22-Nov-2021, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. The patient's last menstrual period was on 27-Sep-2021 and the estimated date of delivery was 04-Jul-2022. On 22-Nov-2021, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products (2 doses of BioNTech)). On 29-May-2022, the patient experienced COVID-19 (Rebound of Symptoms such as congestion, body aches). On an unknown date, the patient experienced MATERNAL EXPOSURE DURING PREGNANCY (Maternal exposure during pregnancy). The patient received mRNA-1273 (Moderna COVID-19 Vaccine) beginning around the  eighth week of the pregnancy.  The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) from 16-May-2022 to 21-May-2022 for COVID-19 treatment, at an unspecified dose and frequency. At the time of the report, COVID-19 (Rebound of Symptoms such as congestion, body aches) had not resolved and MATERNAL EXPOSURE DURING PREGNANCY (Maternal exposure during pregnancy) and INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products (2 doses of BioNTech)) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 23-May-2022, SARS-CoV-2 test: negative (Negative) Negative. On 29-May-2022, SARS-CoV-2 test: positive (Positive) Positive.         The patient was taking other medications/products within 2 weeks of starting COVID-19 treatment. The patient previously received a COVID-19 Vaccine. The patient experienced symptoms included congestion, body aches. Device date was reported as 29-May-2022.  Company comment: This is a spontaneous pregnancy case concerning a 32-year-old, patient with no reported medical history and with vaccine history of receiving first and second dose of Covid-19 BioNTech. Patient received third dose of mRNA-1273 vaccine in Covid-19 vaccination in series with gestational age of 8 weeks. Patient experienced the unexpected non-serious AESI event of Covid-19. The event occurred approximately during the third trimester of pregnancy or approximately 5-6 months after the third dose of mRNA-1273 vaccine administration. Allegedly the event was described as, at 33 weeks age of gestation patient took Nirmatrelvir + Ritonavir (Paxlovid) for treatment of Covid-19 for 5 days. Approximately 2 days after the last dose of Paxlovid, patient was tested negative on a home antigen test. Approximately 8 days after the last dose of Paxlovid, symptoms of congestion and body aches reoccurred. No other information surrounding the event was reported. The outcome of the event was not resolved. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a spontaneous pregnancy case concerning a 32-year-old, patient with no reported medical history and with vaccine history of receiving first and second dose of Covid-19 BioNTech. Patient received third dose of mRNA-1273 vaccine in Covid-19 vaccination in series with gestational age of 8 weeks. Patient experienced the unexpected non-serious AESI event of Covid-19. The event occurred approximately during the third trimester of pregnancy or approximately 5-6 months after the third dose of mRNA-1273 vaccine administration. Allegedly the event was described as, at 33 weeks age of gestation patient took Nirmatrelvir + Ritonavir (Paxlovid) for treatment of Covid-19 for 5 days. Approximately 2 days after the last dose of Paxlovid, patient was tested negative on a home antigen test. Approximately 8 days after the last dose of Paxlovid, symptoms of congestion and body aches reoccurred. No other information surrounding the event was reported. The outcome of the event was not resolved. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.