The menstrual cycle is a term used to describe the sequence of events that occur within your body as it prepares for the possibility of pregnancy each month. A menstrual cycle is considered to begin on the first day of a period. The average cycle is 28 days long; however, a cycle can range in length from 21 days to about 35 days.

The steps in the menstrual cycle are triggered by the rise and fall of chemicals in your body called hormones. Your pituitary gland (in your brain) and your ovaries (in your reproductive tract) make and release certain hormones at certain times during your menstrual cycle that cause the organs of your reproductive tract to respond in certain ways. The specific events that occur during your menstrual cycle can be described as follows:

• The menses phase: This phase, which typically lasts from day one to day five, is the time when the lining of your uterus is actually shed out through your vagina if pregnancy has not occurred. Most people bleed for three to five days, but a period lasting only two days to as many as seven days is still considered normal.
• The follicular phase: This phase typically takes place from days six to 14. During this time, the level of the hormone estrogen rises, which causes the lining of your uterus (called the endometrium) to grow and thicken. In addition, another hormone — follicle-stimulating hormone — causes follicles in your ovaries to grow. During days 10 to 14, one of the developing follicles will form a fully mature egg (ovum).
• Ovulation: This phase occurs roughly at about day 14 in a 28-day menstrual cycle. A sudden increase in another hormone — luteinizing hormone — causes your ovary to release its egg. This event is called ovulation.
• The luteal phase: This phase lasts from about day 15 to day 28. After the egg is released from your ovary, it begins to travel through your fallopian tubes to your uterus. The level of the hormone progesterone rises to help prepare your uterine lining for pregnancy. If the egg becomes fertilized by a sperm and attaches itself to your uterine wall, you become pregnant. If pregnancy does not occur, estrogen and progesterone levels drop and the thickened lining of your uterus is shed during the menstrual period.

Ovulation 

A woman is born with all of the eggs she will ever have. Each month a woman who is ovulating normally will drop one egg, this process is called ovulation.

During the hours leading up to ovulation when the mature egg is released from the dominant follicle, some important processes begin:

• The production of the LH hormone (lutenizing hormone rises in the blood).
• A few hours before ovulation, the primary oocyte undergoes a cell division process (meiosis) which results in an egg that contains 23 chromosomes
• The follicle cells surrounding the oocyte secrete mucous, forming a circular barrier (the cumulus) around the oocyte. Beneath the cumulus is a glassy looking membrane the zona pellucida. Sperm must be able to go through the cumulus and the zona pellucida of the egg in order to fertilize it.
• The egg is released and is picked up by the fimbriated ends of the fallopian tube.
• Fertilization usually occurs in the fallopian tube 12-24 hours after ovulation.

Tracking Your Fertile Time

Tracking Your Basal Body Temperature (BBT)

Keeping track of your Basal Body Temperature (BBT) is a way to document whether you have ovulated. A specific hormonal change during your cycle triggers a rise in basal body temperature. By taking your temperature every day you can chart the rise of your temperature and the day you ovulate. The BBT chart will not predict when you are going to ovulate, but can serve as a record of your patterns. This will be helpful information for your physician. Ovulation predictor kits are designed to help you predict the time you will ovulate.

Using Ovulation Predictor Kits

Urine test kits to monitor lutenizing hormone (LH) are called ovulation predictor kits. They are designed to help you predict the time you will ovulate so that you can maximize your chances of getting pregnant. Most kits typically require you to perform a simple urine test. When you urinate on a special stick from this kit, it will document the surge of LH released by the pituitary just before ovulation, usually 24-38 hours before the egg is released. Most kits offer clear instructions for use and a toll-free number to call if you have questions.

Am I Ovulating

here are only about 2 days a month when are you most likely to get pregnant. Identify the most fertile days within your cycle and then plan intercourse to correspond with these times of peak fertility.

• Every month an egg matures, leaves the ovary and travels down one of your fallopian tubes. This is called “ovulation”.
• Ovulation is primarily triggered by a monthly surge in a hormone referred to as “LH” (Luteinizing Hormone). The level of LH rises during the 24-36 hours before ovulation this is the “LH Surge”.
• Your best chance to become pregnant occurs when you have intercourse within 24-36 hours after the LH surge.
• Women’s menstrual cycles can vary from 20-44 days.  This means the day of the month you ovulate can vary significantly. Most women do not ovulate mid-cycle. With so much variability, it may be difficult for a woman to find her peak fertility.
• Become familiar with your cycle by using ovulation tests before you’re actually ready to get pregnant. Ovulation Tests help you to identify the timing of your “LH Surge”: †

† Certain medical conditions and drugs can adversely affect the reliability of tests for predicting ovulation.

Source: Resolve.org

Source: ClevelandClinic.org