Note: The hardcopy of the booklet contains additional diagrams and photos.
There are many possible reasons why a child may grow slowly, including: hereditary factors (short parents), diseases affecting the kidneys; heart, lungs or intestines; hormone imbalances; severe stress or emotional deprivation; infections in the womb before birth; bone diseases; and genetic or chromosomal abnormalities. The purpose of this booklet is to examine one of the common genetic disorders associated with short stature.
In 1938, Dr. Henry Turner recognized a pattern of short stature and incomplete sexual maturation in otherwise normal females. The common name for this condition is Turner syndrome, after Dr. Turner. A syndrome is a set of features often found in association with each other and believed to stem from the same cause.
Turner syndrome is a genetic disorder that results from an abnormality of a chromosome. Chromosomes are thin strands of material found in the nucleus of each cell. They contain the genes that determine each person's characteristics. Every individual has 22 pairs of chromosomes and 1 pair of sex chromosomes (called X and Y). The sex chromosomes determine whether an individual is male or female; they influence height as well as development of sexual organs. A female ordinarily has 2 X chromosomes, while a male has one X and one Y chromosome.
In Turner syndrome, one of the X chromosomes is missing or misshapen in most of the cells in the body. The reason for this total or partial loss of the chromosome usually cannot be found, but the loss occurs soon after the baby is conceived. There is nothing either parent can do to prevent this from happening; it is a biological accident for which no one is responsible.
Because only one X chromosome is present, the ovaries do not develop normally and usually do not function fully. This means that they do not produce adequate amounts of female hormones, so the young teenager will not go through puberty (develop breasts and menstruate) unless these hormones are provided. Pubic and axillary hair may grow, however. Having undeveloped ovaries also means that the woman is quite likely to be infertile, although there are rare cases of women with Turner syndrome conceiving children. Only the ovaries are affected; the uterus (womb) and vagina are normal, so adult sexual function is unaffected. The missing or abnormal chromosome does not mean that girls with Turner syndrome are not really female; they are women with a condition that causes poorly developed ovaries and short stature.
Girls with Turner syndrome are shorter than their peers and reach an average adult height of 4 feet 8 inches, although a few women may reach or exceed 5 feet in height. Their body proportions are normal. Some affected girls have excess skin folds around the neck and puffy hands and feet at birth. this puffiness often disappears during infancy and the extra neck skin becomes less noticeable. Girls with this syndrome may have many middle ear infections during childhood; if not treated, these chronic infections could cause hearing loss. Kidney, heart, thyroid and skeletal problems are more common in females with Turner syndrome than in the rest of the population. Other features that may be observed include abnormal nails (soft and turned up at the tips), webbed neck, low hairline and a broad chest with widely spaced nipples. Few women with Turner syndrome exhibit all of these features; some have only undeveloped ovaries and short stature, with none of the other physical findings or problems.
Mental retardation is not a feature of Turner syndrome, despite such claims in older medical textbooks. Thorough psychological studies show that these women are normal intellectually, but often have a characteristic pattern of intellectual functioning. While their verbal 10 usually is average or above, their non-verbal IQ may be considerably lower because of problems visualizing objects in relation to each other. This difficulty may show up in poor performance in math, geometry, and tasks requiring manual dexterity or sense of direction. It is important to have psychological testing performed promptly if school problems arise. Some experts suggest that all girls with Turner syndrome have this testing done in the early grades in school, so that teachers can pay special attention to helping the girl compensate for any problems that exist.
Girls with several of the characteristic features of Turner syndrome may be diagnosed during infancy or early in childhood. Girls without any of the obvious features may not come to a doctor's attention until they or their parents express concern about poor growth of lack of sexual development. All girls who are very short for their age or growing less than two inches a year should see a doctor.
Although the doctor may suspect the diagnosis on the basis of a physical exam, a laboratory test is needed to confirm it. The best test for diagnosing Turner syndrome is called a karyotype. The doctor draws a small amount of blood and sends it to a laboratory where highly trained specialists are able to separate the chromosomes in the white blood cells. They count the chromosomes and examine them carefully for abnormalities. This is a very difficult task, and it should be done only in laboratories with highly trained, experienced personnel. The diagnosis is confirmed if only one X chromosome is present in some or all of the cells examined, or if 2 X chromosomes are present, but one is misshapen.
If the diagnosis of Turner syndrome is made by a pediatrician or geneticist (doctor specializing in genetic problems), that doctor is likely to refer the girl and her family to a pediatric endocrinologist, a doctor who specializes in children's hormone and growth problems.
Other medical conditions may occur in girls with Turner syndrome, some of them requiring treatment. Kidney abnormalities are present in 25 to 30% of girls with Turner syndrome and may not be detected until kidney damage has occurred, so many doctors screen for kidney abnormalities routinely. The doctor will check the girl's heart and hearing regularly, and will be alert for signs of thyroid hormone deficiency, which may occur in these girls.
As the girl nears 10 years of age, the doctor may treat her with a low dose of an androgen (male-type hormone) or estrogen (female-type hormone) to increase her growth rate; during this 1 to 2 year treatment period, the girl's growth rate may double. Treatment with biosynthetic growth hormone, alone or combined with a low dose of an androgen or estrogen, appears to be effective in increasing adult height in many of these young women, although long term studies are still underway. When the girl reaches 13 or 14, the doctor will prescribe female hormones (estrogen alone at first, then combined with progesterone) to bring about sexual development. Over the course of 1 to 2 years, the girl will develop breasts and feminine contours and begin to menstruate. This menstrual bleeding is not associated with ovulation (the release of an egg from the ovaries) in the vast majority of cases. Most women with Turner syndrome will need to take female hormone pills throughout their lives, although in some cases the woman's doctor may suggest stopping this treatment when the woman reaches the age at which most women are going into menopause.
Psychological treatment consists of counseling for parents and child at various stages Of childhood and adult development. It starts with explanations of the medical condition for the parents as soon as the diagnosis is made. It is very important that the parents, and later the girl herself, have a good understanding of Turner syndrome and its implications, as well as of the ttreatment plan the doctor suggests. The doctor should answer any specific questions each family may have.
While many girls with Turner syndrome excel in their school work, psychological follow-up may be useful in making decisions regarding school. A complete psychological evaluation will pinpoint areas of weakness, if any exist, and will assist teachers and counselors in planning appropriate teaching strategies. Girls with Turner syndrome may be teased during childhood and adolescence because of their short stature; counseling can help them develop healthy ways of coping with this stress. As the time for hormone therapy approaches, both the parents and
young woman should be involved in learning about the treatment and deciding when to begin it.
As the young woman begins to date, she may feel unsure about when and what to tell her boyfriend. This uncertainty about disclosing her condition may come up with girlfriends and adults, as well. Talking about this issue with parents, a trusted adult, a counselor, or the doctor may help the young woman find the best answers to these questions. Support Groups made up of women with Turner syndrome are active in many geographic areas; the Human Growth Foundation will provide information about such groups upon request. If no such group exists in a given area, a Women's Center that offers support groups may be a helpful alternative. More information about the psychological and social aspects of growth problems (including Turner syndrome) is available in the HGF book, Short & OK.
Families should be aware of the options a woman has for having children. Although the odds are against a woman with Turner syndrome producing her own eggs so as to become pregnant, new developments involving in vitro fertilization and embryo transplants offer these women the opportunity to carry a child through pregnancy and give birth. A woman who is interested in exploring these options should ask her doctor to refer her to the appropriate specialist. Adoption is also an excellent option.
If the girl with Turner syndrome and her parents obtain good medical and psychological care, the chances for a satisfying, happy and healthy life are excellent. For information about clinical trials that may be in progress you can visit the Center Watch trial listings for Turner Syndrome Trials.
Author: Patricia A. Rieser, Family Nurse Practitioner-C
University of North Carolina at Chapel Hill
From original text by: Thomas Aceto, Jr., MD and Anke A. Ehrharadt, PhD
Copyright © 1974, Human Growth Foundation, Inc.
All rights reserved.
The Human Growth Foundation is a national, voluntary, non-profit organization dedicated to fostering research in science and medicine; education for physicians and support of training for growth specialists; public education and patient outreach; and education of and personal support for families, parents of children, and adults; and, advocacy for the diagnosis and treatment of disorders of growth in children and growth hormone in adults. The members of the Foundation are concerned parents and friends of children with growth problems and adults with growth hormone problems, and interested health professions
