The patient suffered from Immune Thrombocytopenia. autoantibodies against the glycoproteins GP2B/3A.
On labs, you’ll see: increase in megakaryocytes; on the question stem they’re described as “rare but large.” Megakaryocytes are not suppressed.
She has ITP/immune thrombocytopenia, so she has autoantibodies against her platelets, specifically GPIIb/IIIa. She has the large megakaryocytes because her bone marrow is trying to churn out platelets. She’s a woman of child-bearing age with increased bleeding time but no other neurologic abnormalities/renal issues/fever, so think ITP.
I got tricked into picking the "acquired antibodies against P1A1". Human platelet Ag platelet antigen P1-1a, located on integrin β3, is the main target for responsible for neonatal thrombocytopenia.https://www.jimmunol.org/content/194/12/5751
She has Bernard Soulier Disease page 419 of first aid 2019