Hesperian Health Guides

Menstrual Periods

In this chapter:

About once each month during the reproductive years, people who can become pregnant have a few days when a bloody fluid leaves the womb and passes through the vagina and out of the body. This is called a menstrual period, a period, monthly bleeding, or menstruation. It is normal and is part of preparing the body for pregnancy.

women from different cultures talking
People around the world have many different names for their menstrual periods
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Many people accept their periods as a normal part of their lives. But they may not know why they happen or why they sometimes change.

The Menstrual Cycle

Everyone’s menstrual cycle is different. If you start counting on the first day of a person’s period, most people will begin bleeding again after about a month. But some bleed as often as every 20 days or as little as every 45 days.

The amount of the hormones estrogen and progesterone produced in the ovaries changes throughout the menstrual cycle. After a menstrual period, the ovaries make mostly estrogen, which causes a thick lining of blood and tissue to grow in the womb. This is where the egg will implant and grow if it is fertilized that cycle.

About 14 days before the end of the cycle, an egg is released from one of the ovaries. This is called ovulation. The egg then travels down a fallopian tube toward the womb. This is when the person is fertile and can become pregnant. If they have had penisin-vagina sex recently, a sperm may join with the egg. This is called fertilization. The fertilized egg continues through the tube to the womb and if it implants in the thickened lining, this is the beginning of pregnancy.

You may notice that the time between your periods changes as you grow older, after giving birth, while breastfeeding, or because of stress or illness.

The egg is not fertilized during most cycles, so the lining inside the womb is not needed. The ovaries make less estrogen and progesterone, and the lining is shed from the womb. This is a menstrual period. When the lining inside the womb leaves the body during a period, the unfertilized egg comes out too. After the menstrual period, the ovaries start to make more estrogen again, and the lining of the womb begins to thicken again.

The menstrual cycle
four drawings that show the changes in a woman's reproductive parts during the monthly cycle
If there is no pregnancy, the lining breaks down and is shed
5 to 7 days after a menstrual period
lining of the womb
Ovaries make estrogen to thicken the lining in the womb.
When the ovary
releases an egg
...the lining has thickened..
5 days after ovulation, the lining is rich with nutrients and blood vessels.
Most menstrual cycles take about a month, lasting from 23 to 36 days.

Problems with menstrual period

If you have problems with your menstrual period, talk with family members or friends who may have similar problems and ideas for solutions. Or talk with a health worker.

Changes in bleeding

Menstrual cycles may change over time. Young people whose periods have just begun and people who recently gave birth or stopped breastfeeding may only bleed every few months, bleed very little, or bleed heavily. Their cycles usually become more regular with time.

People who use hormonal family planning methods sometimes bleed in the middle of their cycle. See Where_Women_Have_No_Doctor:Hormonal_Methods_of_Family_Planning|Chapter 13]] for more about changes in bleeding caused by these methods.

People close to menopause may have heavier bleeding or bleed more often than when they were younger. They may also stop having monthly bleeding for a few months and then have it again. It is still possible, though very unlikely, to become pregnant during this time. Using condoms can help prevent pregnancy until you are sure you have reached the end of your fertile years.

Pain from your menstrual period

During your period the womb squeezes to push out the lining. This squeezing can cause pain in the lower belly or lower back, sometimes called cramps. The pain may begin before bleeding starts or just after it starts.

What to do:
illustration of the below: a thumb pressing on a hand
Press hard on the tender place between your thumb and first finger to ease pain from cramps. For other pressure points to ease pain from your period, see "Acupressure Massage."
  • Rub your lower belly. This helps the tight muscles relax.
  • Fill a plastic bottle or some other container with hot water and place it on your lower belly or lower back. Or use a thick cloth soaked in hot water.
  • Drink raspberry leaf, ginger, or chamomile tea. Ask others in your community about local remedies that help with this pain.
  • Keep doing your daily work, if possible.
  • Try to exercise and walk.
  • Take a mild pain medicine. Ibuprofen works very well for the pain that comes with your period.
  • If you also have heavy bleeding and nothing else works, a combined hormonal family planning method, such as combined pills or a hormonal IUD, may help.

Pre-menstrual Syndrome (PMS)

Some people notice one or more discomforts a few days before their period begins. Called pre-menstrual syndrome (PMS), signs include:

  • sore breasts
  • an uncomfortable fullness in the lower belly (bloating)
  • feeling extra tired
  • oiliness or spots (pimples) on the face
  • feelings that are especially strong or harder to control
four young women playing basketball
Exercise can sometimes help with the discomforts of PMS.
What to do:

Try different things and notice what works for you. First, try the suggestions for pain from your menstrual period, then try these ideas;

  • Eat less salt. Salt makes your body hold extra water, which makes the full feeling in your lower belly worse.
  • Avoid caffeine (found in coffee, tea, and some soft drinks like cola).
  • Eat foods high in protein (nuts, beans, pulses, fresh fish, meat, and milk). They help your body get rid of extra water, so your belly feels less full.
  • Try plant medicines. Ask the elders in your community which ones work best for this.

Polycystic Ovary Syndrome (PCOS)

People with PCOS may have irregular menstrual periods—periods that are infrequent or have varying numbers of days between one and the next. They may also have acne and increased face and body hair. An ultrasound machine may show many small fluid-filled sacs (“cysts”) on their ovaries.

The cause of PCOS is unknown, but it seems to run in families. Having PCOS increases the difficulty of getting pregnant and the likelihood of developing diabetes and cancer of the womb. The most common treatment for PCOS is combined hormonal birth control pills.

This page was updated:13 Nov 2023