suffering from cramping for two months; her period was absent; late period; this is a spontaneous report received from a contactable reporter (other hcp) from the regulatory authority (ra). the reporter is the patient. regulatory number: gb-ra-webcovid-202202231741314140-vwqud (ra). other case identifier(s): gb-ra-adr 26641734 (ra). a 25 year-old female patient (not pregnant) received bnt162b2 (comirnaty) (batch/lot number: unknown) as dose 2, single for covid-19 immunisation. the patient's relevant medical history and concomitant medications were not reported. patient last menstrual period date was 10dec2021. patient did not had symptoms associated with covid-19. patient was not currently breastfeeding. patient was not enrolled in clinical trial. vaccination history included: covid-19 vaccine (dose 1; manufacturer unknown), for covid-19 immunisation. the following information was reported: menstruation delayed (medically significant) with onset 22jan2022, outcome "not recovered", described as "late period"; dysmenorrhoea (medically significant), outcome "unknown", described as "suffering from cramping for two months"; amenorrhoea (medically significant), outcome "unknown", described as "her period was absent". patient was suffering from cramping for two months, and her period was absent. patient did not have a covid-19 test. no follow-up attempts are possible; information about lot/batch number cannot be obtained. no further information is expected