She has also had cramping. She didn't realize it that night but when she started cramping she thought something was going on; menstrual spotting/the bleeding is getting heavier; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A 66 year-old female patient received bnt162b2 (BNT162B2), administered in arm left, administration date 07Jan2022 15:00 (Lot number: FL3193) at the age of 66 years as dose 1, single for covid-19 immunisation. Relevant medical history included: "blood clot disorder" (unspecified if ongoing), notes: blood clot disorder; "Osteoarthritis" (unspecified if ongoing), notes: She is disabled and she has osteoarthritis and a meniscus tear so she hurts a lot anyways.; "she had COVID last year", start date: 2021 (unspecified if ongoing); "She is disabled and she has osteoarthritis and a meniscus tear so she hurts a lot anyways." (unspecified if ongoing); "cyst by her breast area" (unspecified if ongoing). Concomitant medication(s) included: WARFARIN taken for coagulopathy. Past drug history included: Cortisone shot, notes: she had a cortisone shot in her breast area the only thing they did was drain it. The following information was reported: MUSCLE SPASMS (non-serious) with onset 08Jan2022, outcome "unknown", described as "She has also had cramping. She didn't realize it that night but when she started cramping she thought something was going on"; INTERMENSTRUAL BLEEDING (non-serious) with onset 08Jan2022, outcome "recovered" (28Jan2022), described as "menstrual spotting/the bleeding is getting heavier".  Additional information: She mentioned of having cortisone shots. She received cortisone product in the Dermatologist's office three to four months ago. She had a cortisone shot in her breast area the only thing they did was drain it, she thought they took the core out of the cyst, but they drained it because of the puss and blood that was in it and when they gave her a cortisone shot for 7 days she was bleeding, night and day. She has a blood clot disorder and has been on warfarin for close to 18-20 years. Takes 10mg on Monday/Wednesday/Thursday/Friday nights. Takes 5mg on Tuesday/Saturday/Sunday nights. She was on disability for blood clots. She started spotting and doesn't know if its from the shot or what but the only thing that she has taken was the shot. She also had cramping. She didn't realize it that night but when she started cramping she thought something was going on. She was disabled and she has osteoarthritis and a meniscus tear so she hurts a lot. The spotting hasn't stopped, the bleeding was getting heavier. She wants to know would the Pfizer shot have that reaction. She started bleeding more and more each day. She bleed from that spot. This started the night of 08Jan2022. It lasted until 28Jan2022. After the bleeding slowed down, she started passing clots. She was bleeding day and night and was passing clots until it stopped on 28Jan2022. She also had a lot of cramping and didn't realize that night that something was going on. She didn't ever think it was menstrual spotting because she is 66. The bleeding is heavier. She concerned if she would be contraindicated in getting the second dose of the Pfizer BioNtech Covid-19 Vaccine if she experienced cramping and menstrual spotting during the first dose. In clinical studies of participants 16 years of age and older who received Pfizer-BioNTech COVID-19 Vaccine containing 30 mcg of a nucleoside-modified messenger RNA encoding the viral spike (S) glycoprotein of SARS-CoV-2 (30 mcg modRNA), adverse reactions following administration of the primary series included muscle pain (38.3%).  No follow-up attempts are possible. No further information is expected.