If you have achondroplasia, you have one mutated gene associated with the condition and one unaffected version of that gene. This is the most common cause of dwarfism. This condition affects only females. Instead of inheriting two fully functioning X chromosomes from your parents, you inherit one X chromosome and are missing a second, or at least part of a second, X chromosome. Males, by comparison, have an X chromosome and a Y chromosome.
In many cases, the reasons for growth hormone deficiency are never diagnosed. An underactive thyroid , especially if it develops at a young age, can lead to many health problems, including limited growth. Other complications include low energy, cognitive problems, and puffy facial features. The pregnancy may go to full term, but the baby is usually much smaller than average. The result is typically proportional dwarfism.
Dwarfism is usually the result of a genetic mutation. But having a gene or genes responsible for dwarfism can occur in a couple of ways. In some cases, it can happen spontaneously. You may not be born with mutated genes inherited from a parent. Instead, a mutation of your genes happens on its own — usually without a cause doctors can discover. Inherited genetic disorders can take two forms. One is recessive, which means you inherit two mutated genes one from each parent to have the condition.
The other is dominant. You only need one mutated gene — from either parent — to have the disorder. Other risk factors for dwarfism include a hormone deficiency or malnutrition. Serious malnutrition, which leads to weak bones and muscles, can also be overcome in many cases with a healthy, more nutrient-rich diet. At birth, sometimes the appearance of a newborn may be enough to make a diagnosis of dwarfism. As part of baby wellness exams, your child should be measured and weighed to see how they compare to the population averages for a child their age.
Consistently measuring in the lowest quartiles on the standard growth chart is another sign a pediatrician can use to diagnose dwarfism.
Making a tentative prenatal diagnosis while the baby is still in the womb can be done with an ultrasound. This is a lab test of amniotic fluid from the womb.
Genetic testing may be helpful in some cases. This is particularly true when distinguishing one potential cause of dwarfism from another. A blood test to check for growth hormone levels may also help confirm a diagnosis of dwarfism caused by hormone deficiency. Dwarfism is often accompanied by health complications.
These range from leg and back problems to brain and lung function issues. Pregnancy in those with dwarfism can present its own set of potential complications, including respiratory problems. People with SED also may develop reduced joint mobility and arthritis early in life. So why are people born with dwarfism? In fact, children with achondroplasia are often born to average-size parents.
Doctors can usually treat these cases in childhood. Doctors are able to diagnose most cases of achondroplasia even before birth by doing an ultrasound in the later stages of pregnancy. Little people, their families, and their doctors focus on preventing or treating the health conditions that can happen with dwarfism. Different types of dwarfism bring different health concerns.
Some of the medical complications associated with dwarfism can require surgery usually on the back, neck, leg, foot, or middle ear. Because of this, little people usually go through more surgeries than the average-size person, especially as children. These surgeries require anesthesia, and that can be more of a risk for people with dwarfism because of their smaller body size and airways, and sometimes associated curvature of the spine.
Because of their shorter stature and physical differences in bone growth, children with dwarfism usually learn to roll over, sit up, and walk at older ages than average-size kids. Their bodies may be a little different and it might take them a little longer, but they do figure out how to do it in their own time and in their own way. A few extra pounds on a little person can be more of a problem than a few extra pounds on an average-size person.
Extra weight causes harmful stress on the back and joints. Most of the complications that happen in people with dwarfism are physical in nature and do not affect their intellectual ability. In fact, little people often develop a sense of ingenuity because they often have to find clever ways of doing things in the average-size world.
Treatment often includes providing emotional support for people and families living with dwarfism. Short-statured people often have to interact with people unfamiliar with dwarfism who make assumptions about their capabilities without knowing enough about it or getting to know someone with it.
For short-statured people, meeting others can sometimes be challenging, especially those who are unfamiliar with dwarfism. Reviewed by: Angela L. Note: All information on KidsHealth is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. All rights reserved. Find a Doctor. About Us. Community Programs. California Kids Care. If you have a family history of achondroplasia, you may want to seek genetic counseling to determine your risk of having a child with this condition.
Our doctors may use information from prenatal imaging and genetic tests to make an initial diagnosis. A routine prenatal ultrasound, which uses sound waves to create an image of the baby in the womb, can often detect common characteristics of achondroplasia.
For instance, the ultrasound may reveal shortened limbs or hydrocephalus, which causes a buildup of fluid in cavities within the brain and makes the head appear unusually large. A specialized laboratory examines the fluid to look for the FGFR3 mutation. A chorionic villus sampling test involves analyzing a small tissue sample from the placenta, which carries oxygen and nutrients from a mother to the baby in her womb. The doctor threads a thin tube through the vagina and cervix and into the placenta to remove placental tissue, which is tested to see if it contains an altered FGFR3 gene.
To help confirm a diagnosis, our doctors perform a physical exam and other tests to look for signs of achondroplasia in babies and children. A routine blood test may be recommended to look for an altered FGFR3 gene if prenatal genetic tests have not been performed. They can also be used to help detect spinal stenosis and curvature in the legs and back. In CT scans, many X-rays are used to create cross-sectional, three-dimensional pictures of vertebrae—tiny bones in the spine.
MRI uses magnetic fields to create detailed, three-dimensional images of areas that are more difficult to see on an X-ray, such as the spinal cord. Our pediatric neurologists perform a comprehensive neurological exam to look for signs of spinal cord compression, hydrocephalus, and other neurological problems that are common in babies and children with achondroplasia. A neurological exam is performed during each visit.
During this exam, the doctor usually tests the function of the cranial nerves—12 pairs of nerves that relay sensory information to the brain and help to control facial movement and other functions. The doctor may suggest that you use a home monitoring device to check if your child has signs of sleep apnea during the first few months of life.
The sleep study can help to determine whether your child has a breathing disorder, such as obstructive or central sleep apnea, that interferes with sleep. Either type of apnea wakes a child, and these sleep interruptions can cause excessive daytime sleepiness.
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