she had a follicular cyst; craziest menstrual cycle; burning pain in her lower back so much; excruciating pain in left ovarian pain 8/10./the lower left ovarian pain; inflammatory response; really bad pain; folliculitis; This is a spontaneous report from a contactable consumer (patient). A 33-year-old female patient received bnt162b2 (COMIRNATY), dose 2 via an unspecified route of administration on 20Jul2021 (Lot Number: EW0198) as dose 2, single for COVID-19 immunisation. Medical history and concomitant medications were not reported. Historic vaccine was bnt162b2 received via an unspecified route of administration on 29Jun2021 (lot: EW0191) as dose 1, single for COVID-19 immunization. The patient was asking if there was any information about menstrual cycle irregularities or studies being done that we can provide information from? In Aug2021 she was fine, no health issues. In Sep2021 she had the "craziest menstrual cycle", with burning pain in her lower back so much that she was bedridden with a heating pad. Caller her doctor and kept tested negative for UTI's. Her period went away for a couple of days and ovulation started and she was in excruciating pain in left ovarian pain 8/10. She went to the ER on the 28Sep2021, where they said she had a follicular cyst they did an ultrasound. She went to her OBGYN, her PCP, and a Urologist twice. They did an ultrasound of her kidneys, and ultrasound "for everything" and found nothing wrong. She was still having really bad pain. It flares and comes and goes. Her cycle was due in 4-5 days and she did not know what to do. She had so much pain on her left ovary like its pushing in on her bladder. Urologist asked when she got the covid vaccine and was told to call Pfizer to report her symptoms because there is a cohort study being done. She kept reading that this was happening from an inflammatory response and it should subside in a couple menstrual cycle. She also provided a link to withheld for studies being done and asked what was being done or information being obtained. She went to the ER, and she had seen numerous doctors for the lower left ovarian pain. She had read that some people would have menstrual cycle inflammation (further clarification unknown). In Sep2021 she had her menstrual cycle and she had lots of horrible back pain, lots of lower back pain. A couple days went by and then she ended up having really bad left ovarian pain. She went to the ER they explained yes maybe it was 'folliculitis' that maybe burst we don't know but it was really normal, they said it was really normal don't worry about it. She then do urine test at emergency room, she then go see her general doctor, her urologist and her OB-GYN, and they do urine test, they do pelvic exam everything works normal. She was still experiencing ovarian pain and they can't explain but why and she called her urologist because he asked her in her visit when did she receive the COVID 19 vaccine and she said July and he asked her because people had been having menstrual cycle issues with it (further clarification unknown). So, she was now been told to report this. Like what was she supposed to do? What was the solution? Events resulted in physician office visit and emergency room visit. The outcome of burning pain in her lower back so much, excruciating pain in left ovarian pain 8/10./the lower left ovarian pain, really bad pain was not recovered. The outcome of other events was unknown.