The immediate cause of induction of ovulation in female is the large plasma surge of
progesterone
estradiol
LH
FSH
C.
LH
Ovulation takes place on 14th day of cycle, concentration of LH is highest on 14th day because it has to break the Graafian follicle so as to release the ovum later if the concentration of estrogen and progesterone decrease there is lose of internal lining of uterus and menstural bleeding start.