M/c cause of APH is
Abruptio placenta is defined as the haemorrhage occurring in pregnancy due to separation of a normally situated placenta.It is also called accidental haemorrhage or premature separation of placenta (refer pgno:133 sheila textbook of obstetrics 2 nd edition)
Placenta pre
Abruptio placenta
Vasa pre
Placenta accreta
General obstetrics