she was hospitalized for 4 days and treated for ITP.; nose bleed; Caller states she gave birth to her son 28DEC2020, and she had been exclusively breastfeeding; Caller states she gave birth to her son 28DEC2020, and she had been exclusively breastfeeding; they did a blood count and sent her to the ER because her platelets were 5 or 7, they were low; This is a spontaneous report from a contactable consumer or other non hcp. A 40-years-old female patient received second dose of bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE, formulation: solution for injection, Batch/Lot number was not reported) via an unspecified route of administration, administered in Left arm on 13Apr2021 10:30 (At the age 40-years-old) as single dose for covid-19 immunisation. Medical history included covid-19 from Mar2020 to an unknown date. Family Medical History Relevant to AE(s): None, all have had the Moderna vaccine and no adverse reactions besides fever and pain in the arm but nothing like this. The patient's concomitant medications were not reported. On 10Apr2021 the patient experienced she was hospitalized for 4 days and treated for itp, nosebleed from 13 Apr 2021 to 16 Apr 2021, on 05Apr2021 states she gave birth to her son 28dec2020, and she had been exclusively breastfeeding, on 05Apr2021 they did a blood count and sent her to the er because her platelets were 5 or 7, they were low. The patient was hospitalized for nosebleed from 13Apr2021 to 16Apr2021. Caller states on 13APR2021, she had her second Pfizer Shot. Caller states that night she had a nose bleed so she went to the Urgent Care and they did a blood count and sent her to the ER because her platelets were 5 or 7, they were low. Caller states she was hospitalized for 4 days and treated for ITP. Caller states then she did one treatment for ITP and then she did a second treatment for ITP. Caller states she was hospitalized a couple of weeks later and given treatment. Caller states she is taking a 3rd treatment currently. Caller states her Platelets keep crashing down. Caller states she has blood work drawn every few days and she is being monitored closely to make sure her platelets don't drop too low. Caller states one treatment was given for over a month. Caller states she had 2 dexamethasone treatments, 2 IVIG treatments and now she is on Prednisone and doing a slow taper. Caller states if this doesn't work, they are going to explore other longer-term options. Caller states she has no history of autoimmune disorders or ITP. Caller states when she says ITP, it stands for Immune Thrombocytopenia, or it is also called something else, Idiopathic Thrombocytopenia. Caller states she went to the Urgent Care first for the nosebleed and petechiae and she didn't think anything was probably going on, but they did bloodwork and her platelets were really low so they sent her to the ER and she was admitted to the hospital from 13Apr2021-16Apr2021 for 4 Days. Caller states she was admitted to the hospital a second time 23Apr-26Apr2021 for 4 days. The patient underwent lab tests and procedures which included antibody test: positive, platelet count: 5-7 low on 13Apr2021. Other Conditions tested Positive Antibody IVG Spike Protein and Nucleocapsid; states result from antibody test indicate that she has probably had Covid sometime in the past, only time would have been March 2020 when the pandemic started, she had symptoms that weren't reported as symptoms yet and she was traveling in India at the time. States she doesn't know what strain it may have been. States she tested for antibodies because she was interested to see how the steroid was affecting her response to vaccine. Patient was healthy before vaccination with no allergies. Outcome for the event immune thrombocytopenia, maternal exposure during breast feeding, off label use was unknown, event nosebleed was recovered, event blood count abnormal not recovered.  Information on Lot/Batch has been requested.