Time required for ovulation from the onset of LH surge is: (A) 12 hours, (B) 24 hours, (C) 36 hours, (D) 48 hours
Answer is C. 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.