experienced a period; cramping; back pain; premenopausal; abdominal pain; This is a spontaneous report received from a contactable female consumer (patient). A 52-year-old female patient of an unspecified age received bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE Solution for injection Batch/Lot Number: EW0167) via an unspecified route of administration in the arm left on 13May2021 as dose 1, single for COVID-19 immunisation. Medical history included covid-19 from an unknown date and unknown if ongoing She called her health department this morning because her husband tested positive for Covid yesterday. The patient's concomitant medications were not reported. Additional Vaccines Administered on Same Date of the Pfizer Suspect If applicable, all vaccines administered on same date with the Pfizer vaccine considered as suspect was none. Prior Vaccinations (within 4 weeks) any other vaccinations within four weeks prior to the first administration date of the suspect vaccines was none. On 13May2021, about 4-5 hours after she experienced a period, cramping. On unknown date, May2021 experienced abdominal pain. She is pre-menopausal and previously has not had a period in 6 months. However, she heard on the news that other women were getting a period after receiving the vaccine. A couple weeks, later she began to experience back pain that has not subsided. Has sought treatment from gynaecologist and has upcoming appointment with gastroenterologist. Received second dose of vaccine on 03Jun2021. She stated that she had been fully vaccinated, received her vaccines 13May2021 and the second either 02Jun2021 or 03Jun2021, and it was LOT EW0202 she thinks, or it could be, it is hard to read, EW0702 also but it's one of those two. Both were in the left arm. It was about 11:30 am both times in the morning or so. She has been fully vaccinated for a month and called her health department this morning because her husband tested positive for Covid yesterday. No additional details provided. The health department told her to call Pfizer and talk to Pfizer first about whether it is coincidental or not after the first shot on 13May2021. She went to get checked by her gynaecologist and did tests and ultrasounds. She said she thought it might be inflammation which is common once you get the Covid shot and that could possibly be causing this, and nobody seems to know. The cramping is constant and abdominal pain now. Sometimes it is like cramping and sometimes a dull weird pain. That kind of cleared up after 4 or 5 days and then she had not had another one until yesterday when this started again. She thinks maybe it is partly because she is pre-menopausal. Lower back pain did not start right away and did not notice it until a couple of weeks ago, it is still going on and has everything now. Abdominal pain is worse, it's kind of is mid to lower abdomen pain and seems worse like on the left side. She saw her gynaecologist and they did not do a pap smear because she is not due for it. They did a physical and a pelvic ultrasound and they had that imaging and did not find anything. It was on 22Jun2021. She also felt her ovaries and uterus, and everything felt fine. The adverse event required to visit to physician office. She had an appointment scheduled since she eliminated gynaecological issues, scheduled for the gastroenterologist but can't go until 03Aug2021. She tries not to take pain medication but took Ibuprofen a couple of time is all. The patient underwent lab tests and procedures which included ultrasound pelvis resulted as normal on 22Jun2021. The outcome of the events was unknown.