SPONTANEOUS ABORTION; MATERNAL EXPOSURE DURING PREGNANCY; CHILLS; FEELING UNWELL; JOINT PAIN; SORE ARM; FATIGUE; HEADACHE; MUSCLE PAIN; This solicited pregnancy report received from a patient concerned a 36 year old white female of an unspecified ethnic origin. The patient was enrolled in a non-company sponsored study. The patient's weight was 66.67 kilograms, height was 165 centimeters, and body mass index (BMI) was 24.26. The patient's past medical history included: one previous pregnancy, which resulted in a miscarriage, and concurrent conditions included: multigravida, no history of exposure to drugs for recreational use, tobacco use, or alcoholic beverage consumption. The patient initiated treatment with Covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 1805029, and expiry: unknown) dose was not reported, 1 total was administered on 21-MAR-2021 for covid-19 immunisation. Concomitant medications included prenatal Vitamin and Lamotrigine. On 21-MAR-2021 (gestational age 3 weeks 6 days), the patient had maternal exposure during pregnancy, chills, feeling unwell, joint pain, sore arm, fatigue, headache, and muscle pain. On 11-May2021 (gestational age 11 weeks and 1 day), the study participant experienced spontaneous abortion. No additional details were provided. The first day of the last menstrual period (LMP) was reported to be 22-Feb-2021. The estimated delivery date (EDD) was calculated to be 29-Nov-2021. It was reported that this was singleton pregnancy. The para was 0 and gravida was 2. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from maternal exposure during pregnancy, chills, feeling unwell, joint pain, sore arm, fatigue, headache, and muscle pain on 23-MAR-2021, and the outcome of spontaneous abortion was not reported. The reporter provided no causality assessment. Company causality between covid-19 vaccine ad26.cov2.s, and spontaneous abortion, and maternal exposure during pregnancy was not related, and between covid-19 vaccine ad26.cov2.s, and chills, feeling unwell, joint pain, sore arm, fatigue, headache, and muscle pain was related.  This report was serious (Other Medically Important Condition).  Additional information was received from patient on 27-JUL-2021. The following information was updated and incorporated into the case narrative: Race (white), height (165 centimeters), BMI (24.26), medical history (multigravida, no history of exposure to drugs for recreational use, tobacco use, or alcoholic beverage consumption.), concomitant medication (prenatal Vitamin and Lamotrigine), event (spontaneous abortion), seriousness (serious), outcome (unknown), cessation date of previous events, LMP (22-Feb-2021), EDD (29-Nov-2021), para (0), Gravida (2), and narrative was updated accordingly.; Sender's Comments: V1: 20210728695-Covid-19 vaccine ad26.cov2.s-spontaneous abortion. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: MEDICAL HISTORY 20210728695-Covid-19 vaccine ad26.cov2.s-maternal exposure during pregnancy. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: SPECIAL SITUATIONS