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Biology 103
2001 Second Web Report
On Serendip



"Port wine stains", "stork bites", "angels kisses", "moles", "café-au-lait spots". Sound familiar? They are all birthmarks. Most people have some form of birthmark. Sometimes they are desired and admired (a.k.a. Marilyn Monroe beauty spot), but not always. Many with birthmarks are self conscious of them, especially for cosmetic reasons. Most birthmarks are harmless but there is a genuine case for worry, regard to some forms of birthmarks, which could be a sign of a medical disorder such as malignant melanoma . (1).

So, what is a birthmark? It is an unusual mark or blemish on the skin at birth (Encyclopedia Britannica). It could be permanent or fade and disappear few years after birth. Even to this day, there is very little knowledge about their occurrence. There are many "old wives tales" with regard to the cause of birthmarks such as stress or an unforeseen traumatic experience during pregnancy. One such 'popular' explanation is as follows. "A woman frightened by fire put her hand up to her face and there was a red spot on one side of the child's face when it was born." (9).

However, scientific observations have revealed that a birthmark (also known as nevus) is a result of a development abnormality of the skin (1). One possible cause is that during the embryonic stage of fetal development (first trimester), cells that belong in the mesoderm (blood forming middle germ layer) get displaced in the ectoderm (skin forming outermost cell layer) (1).This leads to proliferation of blood vessels or abnormal pigmentation in the dermal and epidermal structures of the skin, resulting in birthmarks (1).Birthmarks are perceived to be non-hereditary. In addition, twice as many females as males are observed to have various forms of birthmarks. However, scientists have not yet come up with an explanation for these phenomena.

Birthmarks fall in to two main categories, vascular birthmarks, and pigmented birthmarks (1). Vascular birthmarks (also known as hemangioma) are made of the abnormal proliferation of tiny blood vessels (capillaries) and related to vascular skin changes (1).They are rarely fully-grown at birth (2).Hemangiomas observed to be more common among females than males, with 5 times as much females having hemangioma (2).Another interesting observation is that hemangiomas occur predominately in Caucasian people as opposed to dark skinned people. It has also been noted that low birth weight infants of less than 2.2 pounds have a 26% chance of being born with or developing a hemangioma shortly after (2).

The most common type of hemangioma is the strawberry mark, which is a red soft and elevated nub on the skin (1).It could either be congenital or appear shortly after birth and treatment is rarely necessary, as it will disappear on its own by the time, a child is 9-10 years of age (3).Salmon patches/stork bites/angels kisses are macular hemangiomas and are small, pale pink marks that appear most often on the nape of the neck, mid-forehead and the eyelids (1).Caused by capillaries that are visible through the skin, they most often disappear by a child's first birthday (1).The most noticeable and cosmetically disfiguring of all hemangiomas is the port-wine stain (nevus flammeus).

These are flat and permanent birthmarks which are composed of dilated blood vessels and normally red, blue or purple in color (3).They most often appear on the face, neck, and top of shoulder and less frequently around the eyes (3).Observed to occur in three out of every 1000 infants, they most often require medical treatment especially if they are large, lumpy, and disfiguring (4).Popular methods of treatment are laser surgery, steroid injections, surgical excision, and cryotherapy (freezing) (4). If surgical excision of the nevi is impossible due to its large size then treatment must be maintained for life through laser therapy and cryotherapy, because the involvement of the nervous system will make the port-wine stain reappear (3).

The last type of vascular birthmarks are cavernous hemangioma. These are mostly large, red-blue benign tumors, composed of mass of connective and fatty tissue filled with large blood vessels (5).Fully developed at birth, they can grow up to the same size as the body part on which they appear (5).These are however rarely malignant and can be surgically removed if feasible.

Think twice if you thought birthmarks are only skin deep. Birthmarks, especially hemangiomas can even grow inside the body (5).These internal hemangiomas (visceral hemangiomas) are highly dangerous and much more difficult to detect (5). They can occur in the liver, intestines, airways, and the brain (5). Jaundice in newborn babies is suspect to be an indication of liver hemangiomas. Blood in stool is a sign of intestinal hemangiomas, while croupy cough and breathing difficulty in newborns could be due to hemangiomas in the airway (5). These internal birthmarks are observed to be more common among infants with hemangiomatosis (multiple hemangiomas(5).It is important that an ultrasound be done for the entire body in such instances to rule out the possibility of them inside the body.

The second main type of birthmark is the pigmented birthmark, popularly known as the café-au-lait patch for its tan-brown color. Unlike hemangiomas, these are composed of abnormal clusters of pigmented cells and not clusters of blood vessels (1). The pigment melanin is observed to play a role in the formation of this type of nevus. (3). Pigmented skin lesions are permanent and most often found on the torso. Moles are the most common of this form of birthmarks. They come in all shapes, sizes, and colors and have a life cycle of about 50 years. Some are macules (flat spots), while some are conical elevated lesions or papules (6). Others such as Becker's nevus which is more commonly found in males is a pigmented nevus with hypertrichosis (multiple terminal hairs growing on it) (6). Most moles are harmless and rarely pose any health risk. However, the actual risk associated with a specific nevus is still unclear. Therefore, it is feasible to get moles regularly observed and checked by a doctor, if they are particularly large, there is a sudden color change, they bleed, or become ulcerous (3).

A pigmented nevus present at birth such as a congenital melanocystic nevus and nevus sebaceous has a high risk of developing in to malignant melanoma (skin cancer) compared to other forms of pigmented birthmarks (1). Commonly located on the scalp they will develop into rougher, verrucous papules with time and must be medically observed regularly to check for any malignant tumors within the lesion (6). Congenital melanocystic nevi located on the scalp is also associated with seizures, mental retardation, and primal leptomeningeal melanoma if the congenital nevus is an indication of melanocytes (abnormal clusters of melanin) in the leptomeninges of the brain (6).A MRI must be performed to rule out any possibility. In addition to malignant melanoma, congenital café-au-lait spots might be an indication of neurofibromatosis; a rare genetic disease that causes abnormal development of nervous tissues (6). The presence of more than six large café-au-lait spots, particularly among children of less than 5 years is observed to be a very high possibility of neurofibromatosis (6).

Surgical excision of the lesion is the preferred treatment for pigmented birthmarks, especially congenital nevi that have a high risk of becoming malignant. Destructive treatment methods like laser therapy, dessication, curettage (surgical scraping), and cryotherapy is not permanent, since the lesion will reappear eventually (6).Medical treatment is not necessary if they regress naturally with time. Some scientists have used this observation of benign birthmarks, which behave, like cancer cells, to find a treatment for malignant tumors (7).

New Zealand researchers have found two genes in benign hemangiomas called clusterin and cytochrome-b, which they observe, helps in the natural, spontaneous shrinkage of hemangiomas (7).It is discovered clusterin and the protein it produces play a role in apoptosis (programmed cell death) in benign hemangiomas, thus leading to possible regression of the hemangioma with time (7).Cytochrome-b, a gene observed to produce energy in cells, also results in programmed cell death in hemangiomas, particularly when the cells need more energy (7).The aim of this research is to understand what causes both programmatic regression and growth of cells in benign tumors, so these findings can be deployed in combating and controlling malignant tumors in which apoptosis does not happen properly (7).These observations and findings on base information provided by genes helps us to appreciate and understand the complexity and unpredictability of any biological system, including a birthmark.

Finally, I like to draw attention to a unique research conducted by Dr. Ian Stevenson, the head of the Department of Psychiatric Medicine at the University of Virginia School of Medicine on the cause of certain birthmarks. His observations indicate that birthmarks and other skin lesions might be evidence of injuries sustained in a previous life, thus supporting the notion of reincarnation, biologically (8).His extensive and detailed observation of children who claim to remember past lives have revealed that 35% of such children have birthmarks that attribute to fatal wounds on a diseased person (8).Moreover, in 88% of such cases there is a perfect parallelism between the birthmarks and the wounds (8). Most of these birthmarks are puckered, scar like marks, hyperpigmented macules or port-wine stains and the cause of their specific location on the body is still largely a mystery (8).This is definitely an amazing and mind blowing observation that greatly supports the idea of reincarnated birth. However, it should be noted that most of these cases arose among people who culturally believe in reincarnation. Therefore, the validity of these observations can only be tested through more research into birthmarks.

When I started browsing online for a possible web paper topic, my objective was to find an important and highly relevant subject matter. I came across some literature on birthmarks and was about to dismiss them casually, as I doubted the significance of the topic. However, the moment I started reading, I realized I was wrong at first and learned the importance of not taking birthmarks for granted. I myself have a couple of moles on my face and body, which I had tended to dismiss as mere cosmetic nuisance. Not any more. Birthmarks are complex biological assemblies about which we still know very little. Why they occur in only certain people, more females than males, certain parts of the body etc is still largely unknown, even though progressive scientific observation has led to dispelling some of the stereotypes associated with them. Birthmarks are also the 'tip of the iceberg' of more serious conditions like malignant melanoma. Hence, correct diagnosis of the type of birthmark one has is critical for proper treatment. However, if we not dismiss them as merely harmless or as worrisome problems we will be able to explore and understand them better. This is critical for biology.

WWW Sources

1)Birthmarks: lifelong companions, from WWW resources on the Serendip web site.

2) Vascular Birthmarks Foundation, from WWW

3) Birthmarks- what are they and why they happen,

4) Birthmarks, Marshall Brain's How Stuff Works website,

5) Cavernous Hemangioma, from Encyclopaedia Britannica Online

6) Birthmarks: Benign or Worrisome?, from Consultant

7) Cancer Clue in Birthmarks, from WWW

8) Birthmarks and the case for reincarnation, from WWW

9) Birthmarks and Superstitions



Comments made prior to 2007

I think this is a great paper. I also decided to do an informative speech on birthmarks because I have them and my children do not. This really helped me get started. Thank you for the information ... Sunshine, 31 January 2006


Serendip Visitor's picture


Do you have any advice on how to treat these kinds of pigmentation? My sister has a birthmark on the left side of her face and is very self conscious about it.

ness's picture


This is really interesting, especially the reincarnation theory. My son had one on the skin, his right temple, now the birth mark is no longer present on his skin, but has taken form on the patch of hair the birth mark used to hide under. He has blonde hair except for the dark patch whish was originally a birth mark. Interesting a birth mark has changed his pigmentation in that part of the hair only. Birth marks now fascinate me.