During menstruation, you might find a blood clot in the pads you use. Relax, not only you who experience this. Come on, find out more about menstrual blood clot. Clotting blood that comes out during menstruation is a common thing experienced by women, and need not worry too much. However, you still need to be vigilant, because in certain conditions, this may be a sign or symptom of a serious condition. Causes of Blood Clots During Menstruation During the menstrual cycle, the lining of the uterus thickens to prepare for pregnancy. However, if pregnancy does not occur there will be a hormone that signals the lining of the uterus to decay into menstruation. Blood clots during menstruation are generally caused by the release of anticoagulant compounds in charge of thinning blood, do not have enough time to carry out their functions. Especially when menstruation is quite a lot. This blood clot often occurs when menstruation is large, usually at the beginning of the menstrual period.