Most birthmarks do not need to be treated. However, most patients (particularly patients with port-wine stain) with easily noticeable birthmarks seek a treatment for cosmetic reasons. 

Infantile hemangiomas usually shrink gradually and do not require treatment. However, in certain clinical situations, pharmacological or invasive interventions (laser, surgery or embolization) may be indicated. Please click here to go to hemangioma management section for further information.

Venous malformations (or commonly and erroneously called "cavernous hemangiomas") are common birthmarks with various venous abnormalities and may cause significant pain and discomfort depending on the size and location of the lesion, and therefore require treatment (sclerotherapy). 

Arteriovenous malformations (AVM) are fast-flow vascular birthmarks and may grow rapidly; any form of AVM needs to be treated. 

Most lymphatic malformations or lymphatic venous malformations require treatment because of the significant discomfort, associated infections and/or anatomical disconfiguration caused by the malformation.

Other vascular anomalies (or complex vascular or lymphatic birthmarks) need to be treated based on clinical symptomatology.

Overall, it is very important to obtain an accurate diagnosis and to be seen by an experienced physician who is  dedicated to the Vascular Anomalies field. If treatment is necessary, it should be managed by an experienced  physician in the field.