At every well-child visit, newborn through adolescence, your pediatrician will measure your child's height. In part this is because growth is a measure of health and well-being, but your doctor will also be tracking the rate at which your child is growing toward his or her estimated target height. This is calculated with a standardized formula so doctors have an objective measure to identify potential growth problems, called short stature.  

Yale Medicine has expertise in diagnosing and treating short stature and can offer the opportunity to participate in clinical trials offering early access to new treatments.

“We see short stature from all ages, from early childhood up until they’re done growing,” says Anisha Patel, DO, assistant professor of pediatrics at Yale Medicine. “I’ve gotten referrals for a six-month-old who wasn’t growing right, and I’ve seen kids as old as 18.”  

Doctors calculate a child’s final height range based on the genetic potential, figuring out the “mid-parental” height based on the parents’ heights. As the child grows,the height is plotted along a curve to that final range. Children’s growth rates can slow at any age before they reach their final height, which happens just after puberty when growth plates within the bones fuse.

Doctors use a specific formula to determine whether a child's growth problem is one that should be looked at more closely. Sometimes an underlying medical condition is the culprit; if a root cause is identified, treatment for it may improve growth. Sometimes, however, Dr. Patel says, short stature happens for no particular reason.

Short stature for which there is no underlying cause (called "idiopathic short stature") is defined by the U.S. Food and Drug Administration (FDA)  as when a child's height is two standard deviations from the mean or when the predicted height. Based on a left-hand X-ray – this occurs when a boy's post-pubertal height is 5’4” or under; for a girl, the measure is 4’11” or under. (The average height in the United States is 5’9” for men and 5’4” for women).

Though short stature can manifest in early infancy or at any point in childhood, it’s generally noticed as puberty begins – at about 10 years old for girls and 11 years old for boys. The opportunity to address it will end once puberty does, generally before a child turns 16.

“If parents are concerned, then around age 8 to 10 is a good time to get an evaluation, or at least to talk about it with your doctor,” says Dr. Patel. “Otherwise, they might miss the window of opportunity for intervention.”

The causes of short stature vary greatly from child to child. Sometimes it’s a medical reason. Sometimes it’s just a constitutional delay, meaning a child’s bone age and puberty time might lag behind peers, but that he or she is going to get there eventually. "This is what a lot of people call being a late bloomer," explains Dr. Patel.

Some of the reasons growth development may slow include:

• Genetics. When a child’s parents and grandparents are short, the child may also be short; this is known as familial short stature. Also, the target height is merely an estimate and some children simply don't grow as tall as expected.
• Genetic conditions. Several genetic syndromes can lead to short stature, including Prader-Willi syndrome, Turner syndrome and Noonan syndrome.
• Chronic diseases. Growth hormone is produced by the pituitary gland, located in the middle of the brain. Therefore, chronic medical problems that affect the pituitary gland may also affect growth. For example, radiation to the brain can affect pituitary function, so pediatric cancer or its treatment can lead to short stature. Gastrointestinal diseases that impair nutrition, such as inflammatory bowel disease and celiac can affect growth, can also be a cause. Many other conditions can also delay the growth rate, including hypothyroidism, heart disease, kidney disease, immunological disease and several other endocrine disorders.
• Growth hormone deficiency. Some children simply don't produce enough growth hormone, including those born with a poorly developed pituitary gland.
• Malnutrition. Whether caused by an inadequate food supply, an eating disorder, or an underlying condition or treatment that affects appetite, lack of nourishment is a common cause of growth delay.
• Psychosocial stress. “Whether it be exposure to violence because of war or famine or just being in a home environment that’s not very nurturing, children can experience a psychosocial stress that keeps them from growing properly,” Dr. Patel says. “That can be reversed just by removing them from the stressful environment.”

Treatment for short stature depends on the cause. Sometimes addressing the underlying condition (such as malnutrition) can lead to a normal growth rate.

“If it’s malnutrition, we usually simply try to improve nutrition,” Dr. Patel says. “We may prescribe a drug, like cyproheptadine, which is an allergy medication that also can stimulate appetite.”

In other cases, children are treated with hormones (called recombinant growth hormone) that directly induce growth. This may be recommended, for instance, if the cause is a genetic syndrome.

When the child’s short stature is due to constitutional delay – meaning the child is a “late bloomer” who may look quite a bit younger than his peers, but there’s no underlying cause – a doctor may recommend a low-dose testosterone treatment to induce puberty a bit earlier, which will encourage growth.

Growth hormone is approved by the U.S. Food and Drug Administration (FDA) for use in treating a number of causes of short stature, including idiopathic short stature, growth hormone deficiency, Turner syndrome, Prader Willi, Noonan Syndrome, chronic renal disease and when a child is born small for gestational age without catch-up growth. 

The decision to treat with growth hormone can be a complicated one. Growth hormone is expensive, and health insurance coverage varies widely depending on a person’s diagnosis and insurance plan.

In addition to costing more than tens of thousands of dollars per year, growth hormone treatment is intense. Children being treated for short stature with growth hormone require daily injections, along with regular doctor visits to monitor their reaction. 

After six months to one year of treatment, the doctor determines whether it is helping and, depending on the results, whether to continue treatment. Growth hormones can be used to treat children as young as infants and, depending on the response, may be administered through puberty – so a child may be getting daily injections for many years.

“I tell them this is not forever,” says Dr. Patel. “It depends on the diagnosis and response to the treatment. If your child is not responding, I would not see a reason to continue a daily shot. But if the child does respond and there is improvement in growth velocity, then we generally will continue to treat until bones fuse, which is around age 16 for boys and 14 for girls.” 

Children who have growth hormone deficiency may need treatment for life.

Results will vary among individuals, but this treatment tends to work best in children who have growth hormone deficiency rather than if their short stature has a different root cause. Generally, a child who undergoes growth hormone treatment for three to four years for idiopathic short stature may see their final height improved by two to four inches.

Another thing to consider when weighing the use of growth hormones is that the treatment is relatively new, having only been used for about 35 years.

“One huge downside is that we don’t have long-term data about its effects on people,” Dr. Patel says.

Results will vary among individuals, but this treatment tends to work best in children who have growth hormone deficiency rather than if their short stature has a different root cause. Generally, a child who undergoes growth hormone treatment for three to four years for idiopathic short stature may see their final height improved by two to four inches.

Another thing to consider when weighing the use of growth hormones is that the treatment is relatively new, having only been used for about 35 years.

“One huge downside is that we don’t have long-term data about its effects on people,” Dr. Patel says.

A key advantage that Yale Medicine offers regarding treatment of short stature is the opportunity for patients to take part in new treatment trials. Also, Yale Medicine recently expanded treatment locations with new satellite clinics, opening up the possibility of treatment to more patients.

“Many of our doctors go out to communities far away to see patients, which is something new that we’ve started to do in the past couple years,” says Dr. Patel. "We get referrals in these satellite clinics as well, seeing patients who might not be able to access the level of care Yale Medicine provides from their communities."