The beginning of the menstrual cycle marks the onset of puberty. It is a series of changes that takes place regularly in females in preparation for the pregnancy. It takes place every 22 to 35 days throughout the reproductive period (12 to 51 years).
Menstruation is the monthly shedding of the lining of a uterus. The menstrual blood flows from the uterus through the cervix and comes out from the vagina. Menstruation is well known by other terms such as menses, period, menstrual period and menstrual cycle.
Girls start menstruating at the age of 12. Before a girl gets her period, vaginal discharge occurs. It means your period will come soon. However, girls can begin menstruating as early as 8 years of age or as late as 16 years of age. Menopause is the phase during which a female stops menstruating which occurs at the age of 51. Once a woman has attended menopause, she can no longer become pregnant.
Symptoms of Menstruation
The following symptoms may occur in the female during menstruation-
- Lower abdominal cramps
- Mood changes
- Back pain
- Leg pain
- Food cravings
- A mild rise in temperature
- Tenderness in the breast
- Nausea and vomiting in some cases
During the menstrual cycle, one of the ovaries releases an egg and at the same time, hormonal changes prepare the uterus for pregnancy. If ovulation takes place and the egg isn’t fertilized, the lining of the uterus sheds through the vagina. This is called the menstrual period and the cycle starts again. Changes take place in the ovaries and uterine wall due to changes in the hormones in the blood.
Long cycles are common for the first few years after menstruation starts. As the age advances, it becomes regular. It can get more irregular as you get close to menopause.
Every female’s menstrual cycle is different from another. Some females get their period on the same day each month and for some, it may get delayed for 3 months which is a cause for concern. Some females bleed more heavily or for a longer number of days than others.
Phases of Menstrual Cycle
The menstrual cycle is divided into four phases-
1. Menstrual phase
This phase is also called the stage of menstrual flow during which bleeding occurs due to rupture of blood vessels and lasts about 2-7 days.
When the egg is not fertilized then uterus lining sheds through the vagina. When pregnancy does not occur, the corpus luteum is replaced by scar tissue.
2. Proliferative phase
This phase is also known as the follicular phase or stage of repair. During this phase, repairing of the uterine lining occurs to create an environment for an embryo to grow. The hypothalamus sends a signal to the pituitary gland to release the follicle-stimulating hormone. This hormone stimulates the ovaries to produce around 5 to 20 small sacs called follicles. Each follicle contains an immature egg.
This phase usually involves 10 days from the first day of the last menstrual period and ends when ovulation starts.
3. Ovulatory phase
During this phase, ovulation (release of a mature egg from the ovaries) takes place and the endometrium lining is fully formed to receive the fertilized ovum.
Ovulation usually occurs on the 14th day in 28 days cycle. The ovulation period is the only time during which you can get pregnant. During this phase, a change in cervical discharge and a rise in basal body temperature occurs.
4. Secretory phase
This phase is also known as the luteal phase. This is under the control of progesterone and oestrogen secreted by the corpus luteum. These hormones prepare the endometrium for pregnancy and implantation.
If pregnancy occurs, the fertilized egg gets implanted in the uterine lining. If pregnancy does not occur, the corpus luteum starts to shrink and leads to a decreased level of oestrogen and progesterone followed by menstruation. The uterine lining will shed during the periods. This phase lasts for about 14 days.
During the menstrual cycle, secretory glands produce an increased amount of mucus to help the sperm to move through the uterus. Similarly, there is increased secretion of mucus by the cervical gland, which lubricates the vagina.
When to consult your health care provider?
If you experience any of the following symptoms then you need to consult your health care provider.
- Bleeding occurs more than 7 days
- Heavy bleeding more than usual
- Bleeding in between periods
- Periods stop suddenly
- Severe abdominal pain during menstruation
- Menstruation has not started yet by the age of 16
- Menstrual cycles are delayed more than 2 months
- You think you might have conceived.
In the above post, we have discussed menstruation and the menstrual cycle. Menstruation is the monthly shedding of the lining of the uterus which lasts for 2-7 days and a girl usually starts menstruating at the age of 12. The menstrual cycle takes place every 22 to 35 days throughout the reproductive period.