skip banner - Return to original view
site viewing options
 
Parents|Medical Information|Professionals|In your area|Campaigns

Congenital Melanocytic Naevi

Background

A congenital melanocytic naevus (CMN) is one of many different types of birthmark that may be found in newborn babies:

  • congenital indicates that the abnormality is present at birth;
  • melanocytic is the adjective derived from the word melanocyte, a type of cell present in normal skin and in certain other organs, whose function is to produce melanin - a brown pigment;
  • naevus is the technical (Greek) word that dermatologists (skin specialists) and paediatricians use to describe any type of birthmark that occurs in the skin, the plural is naevi.

CMNs are classified according to size. A 'small' CMN measures less than 2.5cm across; a 'medium'-sized CMN measures 2.5-20cm across, and a 'large' (sometimes called 'giant') CMN will measure over 20cm across. Small CMNs are found in about 1 in 100 newborn babies: it is one of the most common types of birthmark. Medium CMNs occur in approximately 1 in 1,000 newborns; whereas large CMNs only occur in about 1 in 10,000 newborns.

Characteristics of cmns View Characteristics of cmns

Medical text written October 2001 by Dr D Atherton. Last updated November 2006 by Dr D Atherton, Consultant in Paediatric Dermatology, Great Ormond Street Hospital, London, UK.

 

Tell us what you think of this information...

Print whole article Print whole article

 

This Web Site © Copyright, Contact a Family 2010
Contact a Family, 209-211 City Road, London EC1V 1JN
Tel: 020 7608 8700

Registered Charity No. 284912. Charity registered in Scotland No. SC039169
Company limited by guarantee, registered in England and Wales No. 1633333.
HM Revenue & Customs charity tax reference No. XN54769. VAT Reg. No. GB 749 3846 82

This website is certified by Health On the Net Foundation. Click to verify. This site complies with the HONcode standard for trustworthy health information:
verify here.