First menstrual cycle after shot was extremely painful; First menstrual cycle; after 5 days stopped and then 10 days later started again; Series of inflammatory responses; Felt inflamed or that something was going on with my digestive system; Reflux at night; An afternoon I  leaned forward to pick up something and a liquid came straight into my mouth from my stomach; Leaned forward to pick up something; started feeling a bit dizzy; Leaned forward to pick up something; had vision problems; aura; [could not see clearly]; Feeling very unsteady and unbalanced when standing or walking; Brain fog; Could not think clearly or drive; felt almost disabled; Stomach could not tolerate much food I was eating two or three spoons of food and feeling full; Tender when touching between my thorax and mouth of stomach; Right [leg] was ... tender to the touch; Weak; Vertigo; Right [leg] was swollen [and tender to the touch]; Dizzy; Can not ... sleep peacefully; Could not see clearly; Seeing blurry at times; So many vision problems; Cold sensation down my leg; Migraine; Heart beat at rest is 100; Heart palpitations; Chest tightness; Right leg started to go numb; right arm; Needles and cold sensation down my leg during the day and worst at night; Leg was hurting so much like if I have done 1000 squats I was limping; Problems laying down at night time; Fatigue; This serious initial spontaneous safety report from the United States was received by Novavax on 15-JAN-2023 from a consumer via the web portal.  A female of an unspecified age was vaccinated with intramuscular Novavax Covid-19 Vaccine and Adjuvanted 10 ug/mL suspect Covid-19 vaccine dose 1 on 07-AUG-2022.  The following medical history was reported: Endometriosis and Migraine.  No concomitant medications were reported.  On 09-AUG-2022, 2 days after vaccination, the individual experienced migraine (PT: Migraine) (Serious: Medically Significant). On an unspecified day in 2022, after vaccination, the individual's first menstrual cycle after the shot was extremely painful (PT: Dysmenorrhoea) (Serious: Medically Significant). The individual's menstrual cycle stopped after 5 days and then started again 10 days later (PT: Menstrual disorder) (Serious: Medically Significant). On an unspecified day in 2022, almost 6 weeks after vaccination, a series of inflammatory responses started (PT: Inflammation) (Serious: Medically Significant). The individual started to experience reflux at night (PT: Gastrooesophageal reflux disease) (Serious: Medically Significant) and problems laying down at night time (PT: Unevaluable event) (Serious: Medically Significant). One afternoon, the individual leaned forward and a liquid came straight from her mouth to her stomach, she started feeling a bit dizzy (PT: Dizziness postural) (Serious: Medically Significant), had vision problems with an aura (PT: Aura) (Serious: Medically Significant), and could not see clearly (PT: Vision blurred) (Serious: Medically Significant). The individual was feeling very unsteady and unbalanced when standing or walking (PT: Balance disorder) (Serious: Medically Significant), so she spent most of her time in bed. Between the individual's vision and brain fog (PT: Feeling abnormal) (Serious: Medically Significant), the individual could not think clearly or drive; she almost felt disabled (PT: Thinking abnormal) (Serious: Medically Significant). The individual's stomach could not tolerate much food; she was eating two or three spoons of food and feeling full (PT: Early satiety) (Serious: Medically Significant). The individual felt inflamed in her digestive system, and it was tender when touching between her thorax and mouth of stomach (PT: Tenderness) (Serious: Medically Significant). On an unspecified date in 2022, after vaccination, the individual's right leg started to go numb (PT: Hypoaesthesia) (Serious: Medically Significant) and had needles and cold sensations down her leg (PT: Peripheral coldness) (Serious: Medically Significant) during the day, and worse at night (PT: Paraesthesia) (Serious: Medically Significant). One afternoon, her leg was hurting so much she was limping (PT: Pain in extremity) (Serious: Medically Significant). The individual refrained from working out because she felt so weak (PT: Asthenia) (Serious: Medically Significant) with vertigo (PT: Vertigo) (Serious: Medically Significant). The individual's right leg was swollen (PT: Peripheral swelling) (Serious: Medically Significant). On an unspecified date in 2022, the individual visited the emergency room to rule out a blood clot, and received steroid shots, unspecified anti-inflammatory medication, and a Doppler test, which came back good. The steroids helped with inflammation and the individual felt better, but the numbing and sleepy sensation persisted not only in the right leg, but also in the right arm.  The individual as experiencing so many vision problems (PT: Visual impairment) (Serious: Medically Significant). The individual was fatigued (PT: Fatigue) (Serious: Medically Significant) and dizzy (PT: Dizziness) (Serious: Medically Significant), and it was the sickest she ever felt in her life. On an unspecified date, the individual had an MRI of the brain and it came back clean, then she started having heart palpitations (PT: Palpitations) (Serious: Medically Significant) and chest tightness (PT: Chest discomfort) (Serious: Medically Significant). On an unspecified day in 2023, at the time of reporting, the individual's heart beat at rest was 100 (no units reported) (PT: Heart rate abnormal) (Serious: Medically Significant). Since an unspecified date, the individual could not ride her bike anymore or sleep peacefully (PT: Sleep disorder) (Serious: Medically Significant). On an unspecified date, the individual went to an optometrist, who confirmed her optical nerve was not inflamed, but she was still seeing blurry at times.  Relevant lab tests included: Ultrasound Doppler (Result: Good; 2022), Magnetic resonance imaging head (Result: Clear; unspecified date), and Heart rate (Result: 100 (No units reported); 2023).  At the time of reporting, the event outcome of Migraine was recovered/resolved and lasted for 4 days, with an unknown stop date. The event outcomes of Dysmenorrhoea, Menstrual disorder, Inflammation, Gastrooesophageal reflux disease, Unevaluable event, Dizziness postural, Aura, Vision blurred, Balance disorder, Feeling abnormal, Thinking abnormal, Early satiety, Tenderness, Hypoaesthesia, Paraesthesia, Pain in extremity, Asthenia, Vertigo, Peripheral swelling, Peripheral coldness, Visual impairment, Fatigue, Dizziness, Palpitations, Chest discomfort, Heart rate abnormal, and Sleep disorder were unknown.  A discrepancy was identified in the source document. The consumer reported an important medical event, but all events were non-serious. All events were assessed as serious to match the reported case level seriousness. Sender's Comments: This female of an unspecified age experienced: Asthenia, Aura, Balance disorder, Dizziness, Dizziness postural, Dysmenorrhea, Early satiety, Fatigue, Feeling abnormal, Gastroesophageal reflux disease, Hypoesthesia, Inflammation, Menstrual disorder, Pain in extremity, Paranesthesia, Peripheral coldness, Peripheral swelling, Sleep disorder, Tenderness, Thinking abnormal, Unevaluable event, Vertigo, Vision blurred, Visual impairment, Migraine, Heart rate abnormal, Chest discomfort and Palpitations after vaccination with Novavax Covid-19 Vaccine, Adjuvanted 10 ug/mL. The events Asthenia, Aura, Balance disorder, Dizziness, Dizziness postural, Dysmenorrhoea, Early satiety, Fatigue, Feeling abnormal, Gastrooesophageal reflux disease, Hypoaesthesia, Inflammation, Menstrual disorder, Pain in extremity, Paraesthesia, Peripheral coldness, Peripheral swelling, Sleep disorder, Tenderness, Thinking abnormal, Unevaluable event, Vertigo, Vision blurred, Visual impairment, Migraine, Heart rate abnormal, Chest discomfort and Palpitations were reported as serious. Based on the spontaneous nature of the report, the causal relationship between Novavax Covid-19 Vaccine, Adjuvanted and the reported events is considered Possible.