Hypothyroidism may lead to an increase in bruising. However, research has not definitively proved that this is the case.
Some researchers have theorized that hypothyroidism may affect the blood clotting mechanism in the body.
A 2017 study indicated that hypothyroidism can lengthen the amount of time that blood takes to clot due to a reduction in coagulation factors, which are proteins in the blood that cause it to clot. The study authors also noted that hypothyroidism may weaken the capillaries, making them more likely to leak blood and cause bruising.
However, the study authors highlighted that several other studies contradicted these findings and concluded that the effect of hypothyroidism on bleeding and bruising is yet to be proven.
Weakened capillaries and reduced coagulation factors may also cause other symptoms, such as:
- more frequent bleeding that takes longer than usual to stop
- menorrhagia, or heavy menstrual bleeding
- bleeding gums while flossing or cleaning the teeth
The symptoms above may be related to acquired von Willebrand disease type 1, which is associated with hypothyroidism.
Anyone who experiences an increase in unexplained bruising or bleeding should contact a healthcare professional.
Additionally, people should consider speaking with a doctor if they notice any of the
- joint and muscle pain
- fatigue
- unexplained weight gain
- dry skin
- brittle or thinning hair
- difficulty tolerating cold temperatures
- heavy or irregular menstrual periods
- slowed heart rate
- fertility problems
- depression