about pregnancy; trombosebeen; this case was received via ra (reference number: nl-lrb-00783051) on 18-feb-2022 and was forwarded to moderna on 18-feb-2022. this regulatory authority prospective pregnancy case was reported by a consumer and describes the occurrence of deep vein thrombosis (trombosebeen) in a 29-year-old female patient who received mrna-1273 (spikevax) (batch no. 3004493) for covid-19 vaccination. the occurrence of additional non-serious events is detailed below. previously administered products included for product used for unknown indication: spikevax (moderna vaccin (spikevax) covid-19 vaccin moderna injvlst 0 and5mlcovid-19 vaccin moderna injvlst) on 07-jul-2021. past adverse reactions to the above products included no adverse reaction with spikevax. concurrent medical conditions included maternal vaccine exposure (vaccine exposure during pregnancy week: 2). on 11-aug-2021, the patient received dose of mrna-1273 (spikevax) (unknown route) 1 dosage form. last menstrual period and estimated date of delivery were not provided. on 23-sep-2021, the patient experienced deep vein thrombosis (trombosebeen) (seriousness criterion life threatening). on an unknown date, the patient experienced maternal exposure during pregnancy (about pregnancy). on 10-jan-2022, deep vein thrombosis (trombosebeen) had resolved. at the time of the report, maternal exposure during pregnancy (about pregnancy) had resolved. concomitant and treatment medication information were not provided. company comment: this regulatory case concerns a 29-year-old pregnant female patient with relevant medical history of maternal vaccine exposure, who experienced the unexpected serious event of deep vein thrombosis leg (seriousness criteria- life threatening), 1 month and 13 days after receiving the mrna-1273 vaccine. non serious event of maternal exposure during pregnancy has also been reported. vaccine was administered at 2 weeks of gestation. current condition of pregnancy can be a risk factor for developing deep vein thrombosis. the benefit-risk relationship of mrna-1273 is not affected by this report. seriousness of the event retained as per regulatory authority reporting.; sender's comments: this regulatory case concerns a 29-year-old pregnant female patient with relevant medical history of maternal vaccine exposure, who experienced the unexpected serious event of deep vein thrombosis leg (seriousness criteria- life threatening), 1 month and 13 days after receiving the mrna-1273 vaccine. non serious event of maternal exposure during pregnancy has also been reported. vaccine was administered at 2 weeks of gestation. current condition of pregnancy can be a risk factor for developing deep vein thrombosis. the benefit-risk relationship of mrna-1273 is not affected by this report. seriousness of the event retained as per regulatory authority reporting