Heparin-induced thrombocytopenia (HIT) occurs in up to 1% of patients receiving unfractionated heparin. HIT may occur even when very-low-dose heparin (eg, used in flushes to keep IV or arterial lines open) is used. The mechanism is usually immunologic.
The hair loss can seem more extreme if your hair grew much more than normal during pregnancy, or if you have long hair. Most women will return to their usual hair growth cycle within six months, or between 6 and 12 months after birth.
That's also down to shedding fewer hairs than pre-pregnancy. Expect to lose this volume of hair in the months after the birth. It should fall out gradually, and not in any dramatic way. Your hair won't, in normal circumstances, be any thinner than it was before you were pregnant, just back to its old volume and condition.