Which of the following is not a cause for primary amenorrhea ?

Sheehan's syndrome following severe postpaum haemorrhage cause pituitary necrosis by thrombosis of its vessels, and panhypopituitarism. The woman fails to lactate following delivery, remains lethargic and shows signs of hypothyroidism and coisol deficiency. She requires appropriate hormonal suppo. Reference: Shaw's Textbook of Gynaecology 16th edition page no 328