Spider naevi get their name from their "spider like" appearance. They are small clusters of dilated blood vessels on the surface of the skin, which have a central spot with other vessels coming out of it, like spider's legs. They are also known as spider angiomas and spider telangiectasia and are fairly common. In some instances they can be an indicator of underlying liver disease but in most cases they are completely harmless.
Hormonal changes in the body appear to play a part in the development of spider naevi. It has been linked to increased oestrogen, which makes pregnant women and people with liver disease more prone. Age, weight gain, immobility and sun exposure are other factors that have been attributed to the formation of spider naevi.
Spider naevi are most commonly found on the face and neck although you can get them on other parts of the upper body such as the arms. They are less common on the lower body and are not the same as thread veins or spider veins on the legs.
Anyone can get spider naevi, even children, but women are more prone because of the link to the hormone oestrogen. People with liver disease, especially alcohol related liver disease, are also more likely to develop them. This is again linked to levels of oestrogen in the body.