What is a menstrual cycle?
Most of us think that our monthly periods is our menstrual cycle. The periods are just a part of the menstrual cycle, it consist of much more than that. The menstrual cycle starts with the first day you are bleeding i.e. first day of your period. During each menstrual cycle an egg is developed and is released from the ovaries. The lining of the uterus builds up during this process. If the fertilization of the egg doesn’t happen i.e. pregnancy doesn’t happen, the uterine lining sheds during a menstrual period. Then the cycle starts again. Typically the menstrual cycle lasts about 25-30 days, which is from the beginning of one period to just before the beginning of another.
What are the different phases that go behind a period cycle?
The menstrual cycle consists of four phases:
- Menstrual phase: This phase marks the start of your cycle. It starts with the first day of your period. Basically when the egg from the previous cycle is not fertilised, this phase kick-starts. The uterus created a wall to support pregnancy and when that does not happen, the vagina shed the wall through this process. On an average it last about 3-7 days
- Follicular phase: This stage overlaps with the menstrual phase. When the hypothalamus send signals to the pituitary gland to produce follicle stimulating hormones, this phase comes into activity. This hormone then stimulates the growth of 3 to 30 follicles. Each one of these contains an egg. Later in the phase, as the level of this hormone decreases, only one of these follicles (called the dominant follicle) continues to grow. It soon begins to produce estrogen, and the other stimulated follicles begin to break down. The increasing estrogen also begins to prepare the uterus to thicken its wall. On average, the follicular phase lasts about 13 or 14 days. Of all phases, this phase varies the most in length.
- Ovulation phase: Ovulation is when your ovary releases a mature egg which was the dominant follicle in the previous stage. The egg travels down the fallopian tube toward the uterus to be fertilised by sperm. The ovulation phase is the only time during your menstrual cycle when you can get pregnant. The top symptoms to suggest if you are ovulating are:
- a slight rise in basal body temperature
- thicker discharge that has the texture of egg whites
Ovulation happens at around day 14 if you have a 28-day cycle i.e. right in the middle of your menstrual cycle. It lasts about 24 hours. After a day, the egg will die or dissolve if it isn’t fertilized, but because sperms can live up to 5 days, if you have intercourse 5 days before your ovulation starts, you can still get pregnant.
- Luteal phase: This phase starts right after ovulation. In this phase, the ruptured follicle closes after releasing the egg and forms a structure called a corpus luteum, which produces increasing quantities of progesterone. This hormones’ increase keeps the uterine lining thick and ready for a fertilised egg to implant.
If the egg gets fertilised and pregnancy occurs, your body will produce human chorionic gonadotropin (hCG). This is the hormone pregnancy tests detect. It helps maintain the corpus luteum and keeps the uterine lining thick in order to support the growth of a baby. If you don’t get pregnant, the corpus luteum will shrink away and be resorbed. This leads to decreased levels of estrogen and progesterone, which causes the onset of your period. The uterine lining will shed during your period. During this phase, when pregnancy doesn’t happen, you may experience symptoms of what is popularly known, premenstrual syndrome (PMS).
What is a normal menstrual cycle?
First thing to understand is that every woman’s menstrual cycle is different. What might be normal for you, may not be normal for someone else. Our different body types, lifestyle, food habits etc. all work in tandem to determine our menstrual cycle. Your menstrual cycle might be timely— lasting about the same duration every month — or somewhat irregular, and your period might be light or heavy, painful or pain-free, long or short, and still be considered normal. This mean that “normal” is what’s normal for you i.e. you know the experience and it is not something alien to you. Menstrual flow /periods happen every 21-30 days and last for about 3-7 days (average). The process that goes behind this flow, is your menstrual cycle. Cycle get more regular with age as opposed to when you just hit puberty. As you get closer to menopause, one might observe irregularities again.
How to calculate and track your menstrual cycle?
In today’s day and age there are many apps which help women keep track of menstrual cycle. This is the easiest way to keep tabs on your periods and calculate your cycle but if you want to do it yourself, start by tracking the onset and offset of your period regularly, for a few months. Once you notice you have a regularity, it will give you a good base to start determining your cycle.
You will also have to keep tabs on other factors like:
- How much did you bleed?
- Did you bleed in between two periods?
- Did you experience abnormal pain?
These factors will help you understand what your “normal” cycle is like. For example if your period regularly lasts for 7 days and you experience immense pain the first 2-3 days then that will be your normal, even if someone else bleeds only for 4 days and experiences no pain at all. However if you do observe any discrepancies then it is best to visit your gynecologist and consult what needs to be done. If you are nearing menopause then irregularities are normal.
Menstruation is a process that gives stress to a lot of women and the whole fear around “missing your period” can be difficult to deal with. One must remember that missing your period does not directly imply pregnancy, there is a host of other things that might be the reason behind that. We will save that for another discussion, but bottom line is that if your irregularities worry you then just consult your doctor and you will feel a lot better.