An egg is released. There is a chemical released from the brain LH which triggers the release of a mature egg from the ovary about 24 hours later. Over the counter ovulation predictor kit measure the LH which predicts the window of fertility. The area of release on the ovary then begins to may Progesterone in order to thicken the lining of the uterus. The area on the ovary.
The egg is released. At ovulation the mature follicle in the ovary releases its egg. Ovulation is triggered by a surge of hormones from the pituitary gland, luteinizing hormone (lh).