Most common cause of secondary amenorrhoea-

Ans-B i.e., Pregnancy Secondary amenorrhoea o The absence of menstruation for 3 normal cycles or for 6 months or more in a woman with previous norma menstrual pattern in the absence of pregnancy and lactation. o Pregnancy is the most common cause of secondary amenorrhoea. The causes can be classified as follows: Physiological o Pregnancy o Lactation Pathological o Genital tract # Acquired obstruction (gynatresia) of cervical # Asherman's syndrome following excessive curettage, uterine infection or endometrial tuberculosis, transcervical resection of endometrium for dysfunctional uterine bleeding (DUB). # Vesicovaginal fistula-cause unknown. o Ovarian causes # Surgical extirpation. # Radiotherapy. # Autoimmune disease. # Induction of multiple ovulation in infertility-leading to premature menopause. # Polycystic ovarian disease (PCOD). # Resistant ovarian syndrome-due to absent FSH receptors. # Infections-mumps, tuberculosis, rarely pyogenic infections. # Masculinizing ovarian tumours. # Premature menopause. o Nutritional causes # Anorexia nervosa, bulimia. # Extreme obesity. # Excessive weight loss in athletes and ballet dancers. o Pituitary causes # Insufficiency as in Simmonds disease, Sheehan's syndrome. # Hyperprolactinaemia. # Tumours like prolactinomas and chromophobe adenomas, and Cushing's disease. # Empty sella syndrome. # Drugs-tranquillizers, oral contraceptive (OC) pills, metoclopramide, dopamine blockers, antihypertensives, antidepressants, cimetidine and phenothiazine. o Hypothalamus # GnRH deficiency. # Vigorous exercise. # Pseudocyesis. # Brain tumours. # Anorexia nervosa. o Suprarenal causes # Addison's disease. # Adrenogenital syndrome. # Suprarenal tumours. o Thyroid # Hypothyroidism, chest wall lesions. # Graves disease. o Other causes # Diabetes. # Tuberculosis-liver disease. # Renal disease-due to reduced excretion of LH and prolactin. # Severe anaemia, malnutrition.