This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders in Menstruation, Subject name: Gynaecology & Obstetrics
[{'content': "Cryptomenorrhea occurs due to: \nSelect and explain. \nA. Imperforate hymen, B. Asherman's syndrome, C. Mullerian agenesis, D. All", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is a, i.e. Imperforate hymenRef: Dutta Gynae 6th/ed, p450; Shaw 15th/ed, p96-97* Cryptomenorrhea is defined as occurrence of menstrual symptoms without external bleeding.* Menstrual blood fails to come out from genital tract due to obstruction in the outflow passage.* Causes:CongenitalAcquiredImperforate hymen (commonest)Transverse vaginal septumAtresia of upper third vagina & cervixCervical stenosis following:* Amputation* Cauterization* Conization* 'Radium' treatment for malignant conditions", 'role': 'assistant'}]