An elderly multiparous woman with intrauterine foetal death was admitted with strong labour pains. The patient suddenly goes in shock with cyanosis respiratory disturbances and pulmonary oedema. The most likely clinical diagnosis is:
In the question, the female is :

Multiparous
Advanced maternal age
Fetus is dead.

The patient is having strong uterine contractions and suddenly goes in shock with cyanosis, respiratory disturbance and pulmonary edema. All these favour the diagnosis of amniotic fluid embolism.
Amniotic fluid embolism : It is characterised by an abrupt onset of respiratory distress and coagulopathy.

Amniotic fluid enters the circulation and sets up a disseminated intravascular coagulation, leading to consumptive coagulopathy.
Classically a woman in late labour or immediate postpartum gasps for air, has bronchospasm, becomes cyanotic and undergoes immediate collapse and cardiorespiratory arrest, usually accompanied by hemorrhage. Sudden death is usual.
It is diagnosed clinically.

Risk factors:

Advanced maternal age
Tetanic uterine contraction
Uterine rupture
Premature separation of placenta
Multiparity
Use of uterine stimulants
Cesarean section
Intra uterine fetal death.
Rupture of uterus
Congestive heart failure
Amniotic fluid embolism
Concealed accidental hemorrhage