Hereditary Multiple Osteochondromas—Birth Defects

A birth defect is a problem that happens while a baby is developing in the mother’s body. Most birth defects happen during the first 3 months of pregnancy. One out of every 33 babies in the United States is born with a birth defect.

A birth defect may affect how the body looks, works or both. Some birth defects like cleft lip or neural tube defects are structural problems that can be easy to see. To find others, like heart defects, doctors use special tests. Birth defects can range from mild to severe. Causes can include

• Genetics
• Exposures to medicines or chemicals. For example, alcohol abuse can cause fetal alcohol syndrome.
• Infections during pregnancy
• Certain medicines. Before you get pregnant, talk to your health care provider about any medicines you take.
• Not getting enough of certain nutrients. For example, not getting enough folic acid before and during pregnancy is a key factor in causing neural tube defects.

For most birth defects, the cause is unknown.

Health care providers can diagnose certain birth defects during pregnancy, with prenatal tests. That’s why it important to get regular prenatal care. Other birth defects may not be found until after the baby is born. Sometimes the defect is obvious right away. Other times, the health care provider may not discover it until later in life.

Babies with birth defects often need special care and treatments. The treatments may include surgery, medicines, assistive devices, and therapies.

Centers for Disease Control and Prevention

• Intersex (Medical Encyclopedia)

Hereditary multiple osteochondromas is a condition in which people develop multiple benign (noncancerous) bone tumors called osteochondromas. The number of osteochondromas and the bones on which they are located vary greatly among affected individuals. The osteochondromas are not present at birth, but approximately 96 percent of affected people develop multiple osteochondromas by the time they are 12 years old. Osteochondromas typically form at the end of long bones and on flat bones such as the hip and shoulder blade.Multiple osteochondromas can disrupt bone growth and can cause growth disturbances of the arms, hands, and legs, leading to short stature. Often these problems with bone growth do not affect the right and left limb equally, resulting in uneven limb lengths (limb length discrepancy). Bowing of the forearm or ankle and abnormal development of the hip joints (hip dysplasia) caused by osteochondromas can lead to difficulty walking and general discomfort. Multiple osteochondromas may also result in pain, limited range of joint movement, and pressure on nerves, blood vessels, the spinal cord, and tissues surrounding the osteochondromas.Osteochondromas are typically benign; however, in some instances these tumors become malignant (cancerous). Researchers estimate that people with hereditary multiple osteochondromas have a 1 in 20 to 1 in 200 lifetime risk of developing cancerous osteochondromas (called sarcomas).