Body weight changes, exercise, and stress can all alter menstrual flow, causing light periods. Periods that are lighter than usual are not usually a cause for concern.
People often find that their menstrual flow varies from month to month, and some months are simply lighter than others.
In some cases, a light period can be due to stress or weight loss. It can also indicate pregnancy or a hormone-related condition. Similarly, a person may have spotting or colored discharge that they may mistake for a period.
Read on to learn about some possible causes of light periods, how to identify them, and when to contact a doctor.
Each person’s menstrual flow is individual. It is natural for this flow to vary monthly, and it can also change over time. For example, a person’s period may get heavier or lighter as they get older.
Age
According to the
People in their 40s may experience a change in their period flow during perimenopause. These periods can become irregular, and a person may also have months without them and then have a heavier period later. Additionally, periods can become lighter or heavier.
If a person who used to have regular periods suddenly notices skipped or missed periods, they need to contact a doctor.
A lack of ovulation
Sometimes, a person has irregular periods because their body does not release an egg. This is known as anovulation and can lead to lighter or irregular periods.
Additionally, some people have primary ovarian insufficiency. This
Body weight changes
People with underweight or who quickly lose a large amount of weight may notice that their periods are very light or that they stop altogether. This change
Excessive exercise and eating disorders
Help is available
Eating disorders can severely affect the quality of life of people living with these conditions and those close to them. Early intervention and treatment greatly improve the likelihood of recovery.
Anyone who suspects they or a loved one may have an eating disorder can contact the National Alliance for Eating Disorders, which offers a daytime helpline staffed by licensed therapists and an online search tool for treatment options.
For general mental health support at any time, people can call the Substance Abuse and Mental Health Services Administration 24 hours a day at 1-800-662-4357 (or 1-800-487-4889 for TTY).
Many other resources are also available, including:
- The National Association of Anorexia Nervosa and Associated Disorders
- F.E.A.S.T., which provides support and educational resources to friends and family who want to help someone living with an eating disorder
Pregnancy
During pregnancy, a person’s periods usually stop. However, people may mistake implantation bleeding for a light period. Implantation bleeding is a light amount of spotting that occurs when the egg attaches to the uterine lining.
If a person has spotting after a missed period, they may wish to take a pregnancy test.
Medical conditions
Certain medical conditions that affect hormones can also affect the menstrual cycle. These conditions
Stress
Extended periods of stress can affect the body’s hormones, which can interrupt the regular menstrual cycle. Taking steps to manage stress can help a person’s periods return to their usual flow.
Most menstrual periods consist of about
However, there is wide variation among individuals, and it can be challenging to determine how much blood a person is actually losing.
People need to monitor whether their periods are lighter than usual. They can do this by keeping track of how many tampons or pads they use or by tracking how much blood a menstrual cup collects.
The following may indicate a light period:
- a period that is shorter in duration than is usual for the individual
- fewer pad or tampon changes than usual
- bleeding that resembles spotting over a few days instead of a steady flow
Sometimes, a light period may also cause a reduction in symptoms of premenstrual syndrome, such as reduced back pain, uterine cramping, or mood shifts.
When a person starts using hormonal birth control, such as birth control pills, they may notice that their periods get lighter.
This reduction in blood flow may be because the hormone dosages in birth control pills are low and do not stimulate the uterus to build up a thick lining. As a result, a person may have a light period because there is minimal uterine lining to shed.
People may experience some initial spotting between periods as the hormones start to help regulate their periods.
In some instances, a doctor may recommend that someone with light periods take birth control to help control their cycle. Some types of birth control contain hormones that can help an individual’s cycle become more consistent.
Having a light period is not usually a cause for concern. However, if someone has consistently light periods or starts skipping periods altogether, they need to talk with a doctor.
A person should also contact a doctor if a light period coincides with other symptoms that are causing concern, such as pelvic pain.
Periods can become light due to many different factors, including diet, exercise, birth control pills, perimenopause, and more. Certain health conditions that can cause light periods include thyroid dysfunction, PCOS, and Cushing’s disease.
A light period may appear different between individuals. However, a 2022 review defines a light period as less than 5 mL of blood loss. This is about equal to 1 teaspoon.
People may also experience fewer days of bleeding to consider their periods light.
Early pregnancy can cause light period bleeds or spotting. This occurs when the embryo implants itself into the uterine wall.
In most cases, a light period is not a cause for concern.
Several factors, such as diet, exercise, birth control pills, and health conditions, can cause a light period.
What is most important is that a person listens to their body. If they have concerns about the duration of their menstrual blood flow, they can talk with a doctor for clarification and reassurance.