Menstrual Blood Loss: Average Amount & Factors Affecting Flow

On average, women lose between 2 and 3 tablespoons (30 to 45 milliliters) of blood during a period. However, the amount of blood can vary from woman to woman, and even from period to period for the same woman. Some women may lose only a few drops of blood, while others may lose up to half a cup (120 milliliters).

A number of factors can affect how much blood a woman loses during her period, including:

* The length of her menstrual cycle

* The number of days she bleeds each month

* The amount of estrogen and progesterone in her body

* The presence of any underlying medical conditions, such as uterine fibroids or endometriosis

For most women, menstrual bleeding is not a cause for concern. However, if you are concerned about the amount of blood you are losing, it is important to talk to your doctor.