A period, or menstruation, is the shedding of the lining of the womb. Menstruation is also known as menses. Menses are part of normal sexual health for women during their reproductive years.
Menstruation that includes bleeding from the vagina is found mainly among humans and similar animals, such as primates.
The endometrial tissue is shed from the womb and is released through the vagina.
Women have a period approximately every 28 days; however, there is some variation in this cycle, ranging from a 24-day to a 35-day cycle. A period is part of the woman’s menstrual cycle. It is a sign that the body is working normally.
Fast facts on menstruation
Here are some key points about menstruation.
Periods normally start between the ages of 8 and 16 years.
On average, around 5 to12 teaspoons of blood are shed.
Symptoms of premenstrual syndrome (PMS) include bloating, irritability, and breast tenderness.
Irregular periods affect many women, but if you are concerned, you should see a doctor.
What is a period?
The menstrual cycle lasts an average of 28 days, but variations are possible.
Menstruation marks the beginning of a woman’s reproductive years. From the time when she has her first period, or a few days before, she can become pregnant. Menstruation will end with menopause, usually between the ages of 45 and 55 years.
A young woman will notice her first period because blood will come from her vagina.
A woman has two ovaries, each of which contains a number of eggs. Every month during the reproductive years an egg will be released. Also, every month, the womb prepares a lining in case the egg should become fertilized. If the egg does not become fertilized, the lining is not needed and, together with the egg, it will be shed. We see this shedding as blood. This is what we call a period.
If the egg is fertilized, the womb will need the lining, and it will not be shed. This is why periods stop when pregnancy begins.
When do periods start?
Menarche is the start of periods. It will occur when all the parts that make up a girl’s reproductive system are mature and working together.
A girl’s periods generally begin between the ages of 12 and 14 years, but this can vary from 8 to 16 years. Menstruation is a major stage in a girl’s puberty. It is one of several physical signs that a girl is becoming a woman.
Around 6 months before getting her first period, a girl may detect more clear vaginal discharge. Unless the discharge has a strong odor or causes itchiness, this is normal and nothing to worry about. The periods will occur regularly until the woman reaches her menopause.
Women have a period approximately every 28 days
Hormones are released by the pituitary gland in the brain to stimulate the ovaries during the reproductive cycle. These hormones cause some of the woman’s eggs, which are stored in the follicles of her ovaries, to start to grow and mature.
The follicles start producing a hormone called estrogen. The increased estrogen causes the womb lining to become thicker in preparation for receiving a fertilized egg.
If a woman has had sex within several days of the egg being released and sperm is present in her fallopian tube, the egg may become fertilized and she will become pregnant.
However, it is important to note that pregnancy is possible with unprotected sex at any time during the menstrual cycle.
If the egg is not fertilized, estrogen and progesterone levels will drop, and the lining of the uterus (endometrium) will start breaking down. This marks the start of the period.
The period consists of a small amount of blood and the endometrium. The bleeding is caused by the breaking of fine blood vessels within the womb as the lining detaches itself.
A period generally lasts about 5 days. Bleeding tends to be heavier during the first 2 days. Even when
the blood flow seems heavy, the amount of blood lost is usually around 5 to 12 teaspoons.
Some women experience heavier than normal periods, known as menorrhagia. Menorrhagia should be evaluated by a doctor as it can lead to problems such as anemia, because of a low blood count.
The 10 best period tracking apps
Keep track of your cycle with one of these apps
Premenstrual syndrome (PMS)
Symptoms of PMS may include abdominal cramps and bloating
Premenstrual syndrome (PMS) or premenstrual tension (PMT) is a collection of emotional, psychological, and physical symptoms that are linked to a woman’s menstrual cycle.
Symptoms that may be felt by some women in the days leading up to her period include:
headache, including migraine
pains, especially backache
feeling generally emotional or troubled
lack of concentration
breast tenderness or swelling
slight weight gain
As soon as the period begins and the woman starts shedding blood, the symptoms generally improve. In most cases, symptoms will be completely gone by the time the period has ended.
The following factors may increase the chances of PMS:
high caffeine consumption
a history of depression or other mental illness
smoking and alcohol consumption
a family history of PMS
low levels of some vitamins and minerals, calcium, and B vitamins
The average length of a cycle is 28 days, but it can vary from 21 to 40 days.