Monosomy X (Turner Syndrome)

What is monosomy X (Turner syndrome)?

Turner syndrome is a condition that results from a missing or incomplete sex chromosome. All individuals with with Turner syndrome have only one sex chromosome, an 'X', making all individuals with Turner syndrome female.

Turner syndrome can cause a variety of medical and developmental problems, including short stature, failure to begin puberty, infertility, heart defects and certain learning disabilities. Some features can be present at birth, such as puffiness of the hands and feet. In childhood, Turner syndrome may be suspected primarily because of slow growth or short stature. Girls with Turner syndrome are usually of normal intelligence with good verbal skills and reading skills. Some girls, however, have problems with math, memory skills and fine-finger movements.

How common is Turner syndrome?

This condition occurs in about 1 in 2,500 female births worldwide, but is much more common among pregnancies that do not survive to term (miscarriages and stillbirths). The condition is not related to race, nationality, religion or socioeconomic status. There is usually no family history of the condition.

How is Turner syndrome treated?

The primary treatments are hormone therapies, including growth hormone to increase height and estrogen therapy to begin puberty and achieve adult sexual development. Additionally, a pediatric psychologist or group therapy may be helpful if they have social troubles.


Turner Syndrome Society of the United States

Turner Syndrome Society of the United States "provides health-related resources to patients, families and physicians for the diagnosis and treatment of Turner syndrome."

11250 West Road, Suite G, Houston TX 77065
Phone: 832-912-6006 or 800-365-9944


  • Clin Pediatr. 2006 May;45(4):301-313.
  • Gardner, R. J. M., & Sutherland, G. R. (2011). Chromosome abnormalities and genetic counseling (4th ed.). New York: Oxford University Press, Inc.
  • Jones, K. L. (Ed.). (2013). Smith’s recognizable patterns of human malformation (7th ed.). Philadelphia: Elsevier Inc.

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