vaccination failure; covid-19; low back ache; condition aggravated; pain menstrual; intermenstrual bleeding; this is a spontaneous report received from a contactable reporter(s) (consumer or other non-hcp) from the regulatory authority-web. regulatory number: nl-lrb-00734580. a 23-year-old female patient received bnt162b2 (comirnaty), administration date 29jun2021 (lot number: fe1573) as dose 2, single and administration date 25may2021 (batch/lot number: unknown) as dose 1, 0.3 ml single for covid-19 immunisation. relevant medical history included: "pain menstrual" (unspecified if ongoing), notes: no family history. the patient's concomitant medications were not reported. the following information was reported: vaccination failure (medically significant) with onset 21nov2021, outcome "unknown", described as "vaccination failure"; covid-19 (medically significant) with onset 21nov2021, outcome "unknown", described as "covid-19"; back pain (non-serious) with onset 15sep2021, outcome "not recovered", described as "low back ache"; condition aggravated (non-serious) with onset 15sep2021, outcome "not recovered", described as "condition aggravated"; dysmenorrhoea (non-serious) with onset 15sep2021, outcome "not recovered", described as "pain menstrual"; intermenstrual bleeding (non-serious) with onset 15sep2021, outcome "not recovered", described as "intermenstrual bleeding". the patient underwent the following laboratory tests and procedures: sars-cov-2 test positive: (21nov2021) positive. no follow-up attempts are possible; information about lot/batch number cannot be obtained. no further information is expected