Blood Clots during Period

It is normal to pass blood clots during menses, as along with the blood the thickened lining of the uterus is also being shed and expelled outside the body. In case the abnormal blood clots during period occur, visit your gynecologist as it may then be an indication of other serious medical illnesses.

Normal Blood Clots during Period

A blood clot passed during menses with the menstrual blood is a gelatinous mass that is red or purple in color. Blood clots are formed when enough anticoagulants are not produced by your body due to lack of time; hence, a female who has a menstrual flow that is quick or heavy is very likely to pass blood clots. So passage of blood clots during period is more common in women who have heavy menstrual cycles than those who have light or medium menstrual cycle.

Abnormal Blood Clots during Period

Primary Symptoms

  • The blood clots that are passed are greater than a quarter
  • The quantity of blood clots passed is large
  • The clots are passed after menstruation or in between menses
  • Passage of large blood clots is associated with pain
  • During pregnancy passage of any amount of blood clots is abnormal, whether they are associated with pain or not, and especially if the blood clots are large.

Associated Symptoms

  • Unusual fatigue and tiredness that is aggravated by doing even normal activities
  • Lightheadedness or dizziness
  • Complexion becomes pale and you develop an ashen skin color
  • Fingernail beds appear pale and not pink
  • Irregular menses or suffer from bleeding between menses


  • Obstruction of Menstrual Blood. Any condition that obstructs the passage of menstrual blood out of the uterus can lead to blood clot formation. Blood flow can be slowed down by benign uterine polyps or during menopause when the cervical canal becomes narrower due to reduced estrogen levels.
  • Weight Change. If you have had dramatic changes in your weight recently, either you have gained weight or lost weight, you may pass blood clots during period. This also happens due to hormonal changes that accompany large and sudden changes in your weight.
  • Menopause. Beginning of menopause in females is associated with hormonal changes. During all the reproductive years of a female a delicate balance between estrogen and progesterone is maintained. This balance is disturbed during menopause and can lead to thickening of uterine lining, which causes development of heavy bleeding during periods associated with passage of blood clots.
  • Side Effects of Medications. Certain medications may cause hormonal changes in the body, thereby leading to development of thickened uterine lining. This thickened lining leads to heavier bleeding than usual. This lining is also shed as clots during menses.
  • Miscarriage. A woman who has suffered from a miscarriage may pass large blood clots or large lumps of tissue. In case you are pregnant, it is recommended to go to your physician immediately if you happen to pass large blood clots from your vagina.
  • Enlarged Uterus. Uterus can become enlarged permanently if it has been stretched during pregnancy and has not returned to its original size. In such cases, before getting out of the body, menstrual blood collects and clots results in passage of dark, thickened blood and also blood clots out of the vagina.
  • Uterine Fibroids. Uterine fibroids or leiomyomas are non-malignant tumors of the uterus. They are not always associated with symptoms. However, females with uterine fibroids have increased menstrual bleeding and are also prone to pass blood clots during period.
  • Adenomyosis or Endometriosis. These are conditions where the tissue of the uterine lining grows in places other than the lining of the uterus. In endometriosis, it grows outside the uterus, whereas in adenomyosis, it grows in the uterine muscle. Abnormal periods with heavy blood flow can occur in both of these conditions. This is associated with increased chances of developing problems with menstrual bleeding such as clot formation.
  • Polycystic Ovary Syndrome. It is a condition that is characterized by irregular hormone levels resulting in multitude of symptoms including irregularities in menstruation, prolonged or heavy bleeding during menses, and passage of blood clots during menses, weight gain, abnormal hair growth etc.