How to differentiate Amniotic fluid embolism and Pulmonary embolism?

	Amniotic Fluid Embolism	Pulmonary Embolism
Onset of symptoms	Usually during labour	Any time in pregnancy
Early symptoms	Dyspnoea, restlessness, panic, feeling, cold, paraesthesiae. Usually no pain	Breathlessness, , cough, haemoptysis, pleuritic pain
Coagulopathy	Present	Absent
ECG	Not helpful	S1Q3T3
Chest x-ray:	Pulmonary oedema, ARDS, right atrial enlargement, prominent pulmonary artery.	Segmental collapse, raised hemidiaphragm, unilateral effusion
CTPA	Negative	Positive
Complement levels	Raised	Normal
Serum Fetal Sialyl Tn antigen	Present	Absent