Ovulation is the release of eggs from the ovaries. In humans, this event occurs when the follicles rupture and release the secondary oocyte ovarian cells.After ovulation, during the luteal phase, the egg will be available to be fertilized by sperm. In addition, the uterine lining (endometrium) is thickened to be able to receive a fertilized egg. If no conception occurs, the uterine lining as well as blood will be shed during menstruation.
A woman’s monthly cycle is measured from the first day of her menstrual period until the first day of her next period.
On average, a woman’s cycle normally is between 28-32 days, but some women may have much shorter or much longer cycles.
Ovulation can be calculated by starting with the first day of the last menstrual period (LMP) or by calculating 12-16 days from the next expected period.
Most women ovulate anywhere between Day 11 – Day 21 of their cycle, counting from the first day of the LMP.This is what many refer to as the “fertile time” of a woman’s cycle because sexual intercourse during this time increases the chance of pregnancy.Ovulation can occur at various times during a cycle and may occur on a different day each month. It is important to track your cycle and fortunately there are a number of free fertility charting tools available to help women identify their peak fertile days.
This first half of the cycle can differ greatly for each woman lasting anywhere from 7 days until 40 days.
When your menstrual cycle begins, your estrogen levels are low. Your hypothalamus (which is in charge of maintaining your hormone levels) sends out a message to your pituitary gland which then sends out the follicle stimulating hormone (FSH). This FSH triggers a few of your follicles to develop into mature eggs.
One of these will develop into the dominant follicle, which will release a mature egg and the others will disintegrate.As the follicles mature they send out another hormone, estrogen. The high levels of estrogen will tell the hypothalamus and pituitary gland that there is a mature egg.
A luteinizing hormone (LH) is then released, referred to as your LH surge. The LH surge causes the egg to burst through the ovary wall within 24-36 hours and begin its journey down the fallopian tube for fertilization.Ovulation Predictor Kits (OPKs) work by detecting this LH surge.
The corpus luteum will produce progesterone for about 12-16 days (the luteal phase of your cycle.) If an egg is fertilized, the corpus luteum will continue to produce progesterone for a developing pregnancy until the placenta takes over.
You can begin looking for pregnancy symptoms as early as a week after fertilization. You can also begin testing for pregnancy as early as 7-10 days past your ovulation date with an Early Detection Pregnancy Test.If fertilization does not occur the egg dissolves after 24 hours. At this time your hormone levels will decrease and your uterine lining will begin to shed about 12-16 days from ovulation.
This is menstruation (menstrual period) and brings us back to day 1 of your cycle. The journey then begins all over again.The time of ovulation is one of the most important things a woman should understand about her body since it is the determining factor in getting pregnant and preventing pregnancy.