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    Sirenomelia

    Important
    It is possible that the main title of the report Sirenomelia is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.

    Synonyms

    • mermaid syndrome
    • sirenomelia sequence
    • sirenomelia syndrome
    • sirenomelus

    Disorder Subdivisions

    • None

    General Discussion

    Sirenomelia, which is also known as mermaid syndrome, is an extremely rare congenital developmental disorder characterized by anomalies of the lower spine and the lower limbs. Affected infants are born with partial or complete fusion of the legs. Additional malformations may also occur including genitourinary abnormalities, gastrointestinal abnormalities, anomalies of the lumbarsacral spine and pelvis and absence or underdevelopment (agenesis) of one or both kidneys. Affected infants may have one foot, no feet or both feet, which may be rotated externally. The tailbone is usually absent and the sacrum is partially or completely absent as well. Additional conditions may occur with sirenomelia including imperforate anus, spina bifida, and heart (cardiac) malformations. Sirenomelia is often fatal during the newborn period. The exact cause of sirenomelia is unknown, most cases occur randomly for no apparent reason (sporadically).

    Some sources in the medical literature classify sirenomelia as the most severe form of caudal regression syndrome, a complex developmental disorder. However, recently many researchers have indicated that sirenomelia is a similar, but distinct, disorder. NORD has a separate report on caudal regression syndrome.

    Resources

    March of Dimes Birth Defects Foundation
    1275 Mamaroneck Avenue
    White Plains, NY 10605
    Tel: (914)997-4488
    Fax: (914)997-4763
    Tel: (888)663-4637
    Email: Askus@marchofdimes.com
    Internet: http://www.marchofdimes.com

    NIH/National Institute of Child Health and Human Development
    31 Center Dr
    Building 31, Room 2A32
    MSC2425
    Bethesda, MD 20892
    Fax: (866)760-5947
    Tel: (800)370-2943
    TDD: (888)320-6942
    Email: NICHDInformationResourceCenter@mail.nih.gov
    Internet: http://www.nichd.nih.gov/

    Birth Defect Research for Children, Inc.
    976 Lake Baldwin Lane
    Orlando, FL 32814
    USA
    Tel: (407)895-0802
    Email: staff@birthdefects.org
    Internet: http://www.birthdefects.org

    Genetic and Rare Diseases (GARD) Information Center
    PO Box 8126
    Gaithersburg, MD 20898-8126
    Tel: (301)251-4925
    Fax: (301)251-4911
    Tel: (888)205-2311
    TDD: (888)205-3223
    Internet: http://rarediseases.info.nih.gov/GARD/

    Madisons Foundation
    PO Box 241956
    Los Angeles, CA 90024
    Tel: (310)264-0826
    Fax: (310)264-4766
    Email: getinfo@madisonsfoundation.org
    Internet: http://www.madisonsfoundation.org

    Fetal Hope Foundation
    9786 South Holland Street
    Littleton, CO 80127
    USA
    Tel: (303)932-0553
    Tel: (877)789-4673
    Email: info@fetalhope.org
    Internet: http://www.fetalhope.org

    For a Complete Report:

    This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

    The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

    It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

    This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

    For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email orphan@rarediseases.org

    Last Updated: 6/12/2012
    Copyright 1990, 2002, 2012 National Organization for Rare Disorders, Inc.

    WebMD Medical Reference from the National Organization for Rare Disorders

    Last Updated: May 28, 2015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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