Most common cause of secondary amenorrhea is

C. i.e. (Pregnancy) (447- Ganong 22nd) (422 - Ganong 23rd)* If menstrual bleeding has never occurred the condition is called primary amenorrhea* Cessation of cycle in a woment with previously normal periods is called secondary amenorrhea. The commonest cause of secondary amenorrhea is pregnancy*** Effect of pregnancy on respiration is - Increased tidal volume*** Sec-amenorrhoea is - Absence of menstruation for > 6 months*** Hypothalamic amonorrhoea is seen in - Kallaman *s syndrome**