What causes light periods?

A shift or imbalance in hormone levels is the main cause of light periods, and this condition most often affects women who are approaching menopause. An eating disorder, excessive exercise, or a thyroid condition can also cause a woman to have light periods. Women who use hormonal contraceptives may also experience lighter periods. Light periods can also be experienced by young women who are just beginning to menstruate.

Causes of light periods

Light periods can also be caused by hormonal imbalances or other conditions including:

  • Changes in levels of estrogen or progesterone
  • Eating disorders such as anorexia nervosa
  • Excessive exercise
  • Hormonal contraceptives (birth control pills, patch or injection; intrauterine devices)
  • Menopausal transition
  • Normal adolescence in girls just beginning to menstruate
  • Thyroid disease

Serious or life-threatening causes of light periods

In some cases, light periods may be a symptom of a serious or life-threatening condition that should be immediately evaluated in an emergency setting. These conditions include ectopic pregnancy (life-threatening pregnancy growing outside the uterus). An ectopic pregnancy can cause heavy or light bleeding in a pregnant woman.

Questions for diagnosing the cause of light periods

To diagnose your condition, your doctor or licensed health care practitioner will ask you several questions related to your light periods including:

  • Are you pregnant?
  • Have you always had light periods?
  • When did you first notice that your periods were light or getting lighter?
  • Do you have any other symptoms, such as abdominal pain or cramping?
  • Are you currently using any contraceptive device or medication?
  • What medications are you taking?

What are the potential complications of light periods?

Rarely, light periods may be due to serious diseases, and failure to seek treatment can then result in serious complications and permanent damage. Once the underlying cause is diagnosed, it is important for you to follow the treatment plan that you and your health care professional design specifically for you to reduce the risk of potential complications including:


  1. Heavy, prolonged, or irregular periods. UNC Department of Obstetrics & Gynecology. http://www.med.unc.edu/obgyn/Patient_Care/specialty-services/advanced-laparoscopy-pelvic-pain/heavy-....
  2. Abnormal menstrual periods. UCSF Medical Center. http://www.ucsfhealth.org/conditions/abnormal_menstrual_periods/.

What are light periods?

Light periods are menstrual periods that have an unusually light flow or a very short duration of blood loss. Although the menstrual cycle varies from person to person, most women have a normal period approximately every 28 days. Each period typically lasts from four to seven days. The amount of blood lost during a menstrual period ranges from 20 to 80 milliliters (mL). Blood loss of less than ... Read more about light periodsintroduction


What other symptoms might occur with light periods?

Light periods may accompany other symptoms, which vary depending on the underlying disease, disorder or condition.

Common symptoms that may occur along with light periods

Light periods may accompany other common symptoms including:

Medical Reviewer: Cynthia Haines, MD Last Annual Review Date: Aug 5, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.