This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Normal Menstruation, Abnormal Menstruation, Menopausal Physiology and forsight of conception, Subject name: Gynaecology & Obstetrics
Time required for ovulation from the onset of LH surge is 
Select and explain. 
A. 12 hours, B. 24 hours, C. 36 hours, D. 48 hours
C: 36 hours
Answer: C: 36 hours 
Explanation: From the onset of the LH surge, it takes 34-36 hours and from the peak it takes 10-12 hours to ovulate. The midcycle LH surge is responsible for a dramatic increase in local concentrations of prostaglandins and proteolytic enzymes in the follicle. These substances progressively weaken the follicular wall and ultimately allow a perforation to form.