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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.
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.
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.
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.
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:
- abdominal bloating
- headache, including migraine
- pains, especially backache
- low mood
- feeling generally emotional or troubled
- lack of concentration
- breast tenderness or swelling
- slight weight gain
- binge eating
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:
The average length of a cycle is 28 days, but it can vary from 21 to 40 days.
For many women, the length of the cycle and the amount of blood shed is around the same every cycle. However, some women have irregular periods.
There may be variations in:
- the interval length between periods
- the amount of blood lost
- the duration of bleeding
Irregular periods can have different causes, and treatment will depend on the cause.
It is not unusual to have irregular periods for up to 6 years after the start of menstruation or during perimenopause, when the woman’s body is preparing for menopause.
Many women have missed a period at some time. This could be for no apparent reason, or in anticipation of a pregnancy, or perhaps because of anxiety or tension.
Irregular periods may be caused by a wide range of factors including the following:
- benign lesions like uterine fibroids, endometrial polyps, and scarring
- hormone imbalance
- bleeding disorders
- changes in birth control methods
- infection in the uterus
- cancer of the uterine lining or cervical cancer
Anyone who is concerned about irregular periods should see a doctor.
What is amenorrhea (absent periods)?
Amenorrhea is when a woman stops having periods altogether, usually having missed three periods in a row. It is also used if a girl has not begun menstruation by the age of 15 years.
Reasons for this include:
- excessive exercise or weight loss
- some medications, including birth control
- hormonal problems
Doctors may prescribe hormonal therapy to treat amenorrhea.
This is a medical condition that includes severe uterine pain during menstruation.
Most women experience minor pain during menstruation, but if the pain is so severe that it interferes with normal activity, it is called dysmenorrhea. It may require medication.
Some women experience pain during the days before a period, while others have dysmenorrhea during the period. As menstruation tapers off, the pain generally does, too.
Some women experience both dysmenorrhea and menorrhagia, or excessive blood loss.
The following symptoms may be present:
- cramping and pain in the lower abdomen
- low back pain
- pain that radiates down the legs
- tiredness and fatigue
Dysmenorrhea is more likely in the following groups:
- women over 30 years’ old
underweight or overweight
- those whose periods started before they were 12 years old
Here are some facts about menstruation and pregnancy:
- It is unlikely but still possible to become pregnant if you have sex during your period, depending on the length of your monthly cycle, because sperm can stay alive for up to 5 days.
- The purpose of periods is to prepare the womb for conception. If conception does not take place, the unused egg and lining are shed, and the uterus gets ready to have another try. Periods do not continue during pregnancy because conception has taken place.
- You are unlikely to have a period during pregnancy, but light spotting or bleeding may happen during pregnancy at the time you would normally have had a period.
- Bleeding may occur around week 6, at the time the placenta takes over nourishing the fetus.
- Bleeding can be a sign of an ectopic pregnancy or pregnancy loss. Any bleeding should be reported to a doctor.
Women who experience uncomfortable symptoms related to menstruation may find that treatment offers some relief.
- Painkillers: For period pains and discomfort, painkillers can be effective. These could include acetaminophen (Tylenol), ibuprofen, and aspirin.
- Contraception: The contraceptive pill often eases period pains. The lining of the uterus will be thinner, resulting in less contraction during menstruation.
- Exercise: Exercise has been found to help reduce the level of discomfort and pain experienced by women with period problems.
- Relaxation techniques: These can include breathing exercises, massage, and medication. Some women practice yoga for easing pain and stress.
- Heat treatment: Holding a hot water bottle against the abdomen may help in reducing discomfort.
- Warm bath: Apart from helping with relaxation, a warm bath may also provide some relief from pain or discomfort.
Menstrual products used to absorb or catch the menses come in either disposable or reusable forms.
Disposable menstrual products
- Sanitary pads or napkins: Towels, pads, or napkins are placed in the underwear and absorb the menstrual flow.
- Tampons: These are cylinders that are inserted into the vagina, where they absorb the menstrual flow. They are made from treated rayon or cotton blends, or 100 percent cotton fleece.
Reusable menstrual products
- Cloth pads: These are generally made of cotton, terrycloth, or flannel. They are placed externally. They are washable.
- Menstrual cups: These are inserted directly into the vagina to catch the menstrual flow. They are reusable. There are also disposable versions.
- Reusable underwear: Often called “padded panties,” these are usually made of cotton with absorbent layers sewn on. They can be washed and reused.
- Blanket: Also known as a towel or draw sheet. These are large pieces of cloth that are placed between the legs used during sleep. They can be washed and used again.
A wide range of menstrual products is available for purchase online.