The phases of the menstrual cycle are important to understand both for women who are looking to get pregnant as well as for women wanting to prevent a pregnancy. Knowing about one’s menstrual cycle means that a woman knows when she is most fertile, and she is also able to predict when her next period is due.
Assuming an average cycle of 28 days and counting the first day of menstruation as day 1 of the cycle, the cycle can be broadly classified into 3 different phases.
Menstrual Phase
This is the time when the thickened lining of the uterus is shed. This menstrual phase is characterized by several days of bleeding from the vagina. The bleeding usually lasts between 3 and 6 days and is the monthly menstrual period. Anything between 10 and 80 ml of blood could normally be lost during this time.
During this phase, the lining of the uterus or the endometrium is shed. The endometrium starts to thicken in preparation for conception. However when conception doesn’t occur, the lining is shed by way of a period.
Follicular Phase
This is the time when the ovaries ready themselves to release an egg (follicle) and then go on to release the egg. Ovulation is a part of this menstrual phase. Then length of this phase will determine the length of a woman’s cycle as well as the timing of ovulation.
This phase lasts until the day of ovulation. Some women experience some mild cramping and perhaps slight spotting at the time of ovulation. This is known as mittelschmerz or middle pain.
The last 5 days of the follicular phase are when a woman is most likely to get pregnant if she has unprotected sex. If the egg released by ovulation is fertilized at this time, a pregnancy begins and the woman will miss her next period. The fertilized egg will embed in the uterine lining and so the lining will then not be shed.
Luteal Phase
This menstrual phase starts after the day of ovulation and lasts up to the day before the next period. This is the time when many women tend to have some amount of PMS (premenstrual stress). Mood swings, irritability, feeling overly emotional or angry and physical symptoms such as water retention, bloating, acne, feeling tired and breast tenderness could be experienced. The end of the luteal phase is the end of one full menstrual cycle.