Ovulation
Under the control of various hormones following puberty, brain will send a hormonal signal to the Follicle Stimulating Hormone (FSH) to the ovaries to recruit several follicles to mature each months .As follicles within the ovary race to mature, changes are also occurring within the lining of uterus. Increasing amounts of estrogen stimulate a thickening of the lining of the uterus, known as the endometrium .The thickened endometrium or “bed of grass” is essential for a fertilized egg (egg + sperm = embryo) to attach or implant into the uterine lining. This is an essential process that occurs in preparation for an embryo (fertilized egg that will become a fetus) to attach or implant itself in the uterus and continue it’s development.
Ovulation occurs mid-cycle in response to a series of hormonal changes that are set off by a peak in estrogen, occurring any day from day 10 to 17 of the Follicular phase. This peak in estrogen triggers a brief surge in Luteinizing Hormone (LH), which triggers ovulation within usually 24 hours and occasionally up to 48 hours.
Figure : Ovulation