When to Worry about Your Child's Height: Insights from Pediatric Endocrinologist Mark Henin, MD

Is your child much shorter than peers? While there is nothing wrong with being naturally short, the emotional and psychological aspects can impact a child's self-esteem. Support from family, open communication and counseling can help children navigate their feelings about their height. 

Is being short a medical issue? Not in itself, but growth failure (dropping two percentiles on a child's height curve) can indicate the presence of one. When considering medical care for children who are shorter than their peers, the process starts by consulting a pediatrician who can evaluate the child's growth patterns and overall health. The doctor may recommend a referral to a pediatric endocrinologist, who specializes in hormonal growth and development. 

By taking a proactive and informed approach, parents can ensure that their child receives the best possible care and support for healthy growth and development.

To get the long and short of the issue, we sat down with pediatric endocrinologist Mark Henin, MD, to learn about causes and treatment options to maximize a child's growth. 

Genetic Factors

Genetics play an important role in development. Familial short stature basically says, "Children develop like their parents." If both are short, the child will most likely be short. Providers work this out by obtaining a mean average of the parents' heights. That delivers a ballpark of the estimated height for the child, within two inches above or below. As long as the chart is showing the child is growing steadily on his or her percentile arc, there are no worries, even if that number is between the third and fifth percentile. 

Turner's syndrome is a genetic abnormality in females caused by a missing X chromosome. These girls classically are a 45 X instead of the expected 46 XX, in typical females. On the X chromosome that is absent, a gene is specifically titled the short stature homeobox-containing (SHOX) gene. The SHOX gene is very important for height growth. When one copy is absent, the downstream effect is short stature.

Achondroplasia is a genetic disorder that causes differences in the way the skeletal system develops. It is a condition where a person’s arms and legs are much shorter than average, while the trunk is of relatively normal length. The head is typically larger than average, with a prominent forehead, and the face may appear flattened in the middle. 

This condition is caused by a change (mutation) in the FGFR3 gene, which affects how cartilage is converted to bone, especially in the long bones of the arms and legs.

Down syndrome, also known as Trisomy 21, has notable impacts on growth as well. Children with Down syndrome are born with a lower birth length and grow more slowly than children without Down syndrome. The difference in height becomes more noticeable during three key periods: before birth, in the first three years of life and during puberty. Most individuals with Down syndrome reach their final adult height earlier than typical peers, but their final height is significantly shorter — on average, about three –six inches less than the general population, depending on sex and ethnicity.

Hormonal Disorders

Three hormones can cause poor growth in children, including growth hormone, thyroid hormone and cortisol. 

Growth hormone deficiency is a condition where the body does not make enough growth hormone, a protein produced by the pituitary gland, that is essential for normal growth in children. In children, this deficiency typically leads to slower growth and shorter height than expected for age, often becoming noticeable in early childhood. Children with growth hormone deficiency typically show significant decrease in their growth percentiles, dropping 2 or more percentiles over time. The best way to test for Growth Hormone Deficiency is a procedure called a Growth Hormone Stimulation test. This procedure is performed at our Pediatric Endocrine office and gives very detailed measurements of growth hormone levels over a three hour period. If the diagnosis of Growth Hormone Deficiency is confirmed, treatment with Growth Hormone can be given to children as long as there growth plates remain open.

Thyroid disorders are another common cause of growth deficiencies. One of the many things the thyroid is important for is bone growth and development. Hypothyroidism, most commonly severe forms of hypothyroidism, can lead to a significant decrease in a child’s ability to grow normally. In evaluations, we see a low thyroid hormone level. A pediatric endocrinologist will start Levothyroxine, a thyroid hormone replacement, and carefully manage the dose to ensure growth improvement in order to achieve expected adult height. 

Cushing syndrome is an extremely rare condition caused by the adrenal gland making too much cortisol due to a mass or tumor of the pituitary or adrenal glands. Excess cortisol can impact bone maturation and development and cause pretty significant growth stunting, high blood pressure and weight gain, most prominent in face and abdomen, with disproportionately thin arms and legs. Removal of the tumor will lead to a decrease in cortisol levels and significant improvements of growth.

Nutritional Deficiencies

Weight gain is critical for growth because the body needs nutrients to grow. It also needs adequate sleep and physical activity. Often, patients with attention deficit hyperactivity disorder (ADHD) on stimulant medications, suffer significant appetite suppression as a side effect of their medication. Patterns emerge where their weight falls off and then their growth starts falling off.

When it comes to intense exercise, sometimes girls, in particular, have a significantly lower BMI. The body needs to reach a certain BMI, to help trigger puberty. This short stature can be seen in competitive gymnasts, extreme runners and extreme swimmers. Sometimes they have a significant delay in puberty, and that delay causes a stunting of growth.

Chronic Illnesses

Growth is a luxury for the body. If a child has a chronic condition or illness, such as a congenital heart defect, a kidney defect, significant liver function issues, Celiac's disease or inflammatory bowel diseases (ulcerative colitis and Crohn's disease), their bodies may suffer from malnutrition and inflammation. These contribute to poor growth because the body is shunting resources to correct the chronic inflammation and illness-state related to the disease. 

In Celiac disease, for example, once our gastrointestinal specialist colleagues biopsy and then eliminate gluten from a child's diet, we see a significant increase in growth. Removing the source of the inflammation can lead to rapid improvement in those patients.

Intrauterine growth restriction can cause short stature because of suboptimal prenatal nutrition usually due to a variety of maternal factors. Babies who are born smaller than average may show catchup growth by the age of three. If they don't achieve this catchup growth in time, they are eligible for growth hormone treatment, which is quite effective in treating the growth defect. 

Environmental and Psychological Factors

Severe chronic stress in childhood, such as living in a war-torn country, moving constantly while in foster care or suffering ongoing abuse, can have a significant downstream effect on growth. These difficult environments result in chronically high cortisol levels that suppress growth hormone, preventing adequate bone development and maturation.

The positive is that once children are established in stable, healthy environments, overtime their bodies respond and start to grow more appropriately.

What are the treatment options for short stature?

For a growth hormone deficiency, small gestational age without catchup growth and Turner syndrome, treatment with growth hormone can cause significant improvement in growth and ensure patients achieve their expected, final adult height. 

For hypothyroidism, the treatment is thyroid hormone replacement or levothyroxine. We often see significant improvements in growth once we start the thyroid hormone.

About how many inches can a child expect to grow with treatment?

Girls hit puberty between eight and 12 years of age and boys between 11 and 14. Puberty is very important in stimulating growth spurts in children/adolescents, but also starts the process of growth plate closure which helps naturally halt our growth. If parents have concerns about their child’s growth, it is best to have the child evaluated by a pediatric endocrinologist before puberty. This ensures that if a growth stunting diagnosis is made, the child will have plenty of time to receive treatment and achieve expected height. 

Bone age also impacts how much a child can grow. A child with a young bone age has more time to grow. This is evidenced with constitutional short stature, also known as being a “late bloomer.” These children are smaller and start puberty at a later age than their peers through early adolescence. Once they do start puberty, they often have robust, late growth spurts, catch up with and often times exceed their peers' growth, and ultimately hit their expected adult height. This is a natural variation of growth and does not typically require any medical intervention, just careful follow up.

Are there any long-range negative health effects of growth hormone?

Growth hormone is an injection, and anytime we're injecting something into the skin, skin changes can occur, so we encourage families to regularly change the injection sight.

Growth can worsen or induce scoliosis. We monitor back exams closely, and sometimes we involve our pediatric orthopaedic partners to get their expert opinion about whether growth hormone is safe to continue if we start to see curvature in the spine.

Headaches and vision changes can result due to pseudotumor cerebri or intracranial hypertension. Fluid build-up behind the eyes can halt growth hormone treatment until the issue resolves. Then we will restart on a much lower dose.

The femur and the pelvis fit tightly, but rapid growth can rarely pull them apart, so if a patient complains of hip pain, we take x-rays to ensure treatment is safe to continue

Is it okay to be short?

The vast majority of patients we see have familial short stature or constitutional delay. Nothing is physiologically wrong. Being short is not a health issue. Oftentimes, I reassure families that where there are normal labs and X-rays along with bone age delays, the child has overall healthy growth. 

On the other hand, poor growth along with falling off the growth curve, can be a sign of a hormonal issue, endocrine disorder or disease state. 

If a child needs support with growth, our WakeMed Pediatric Endocrinology providers can conduct a thorough assessment, including growth hormone levels and other hormonal evaluations, identifying underlying conditions that may be affecting growth.