Achondroplasia is a birth defect that affects a baby’s bone growth. Birth defects are health conditions that are present at birth. Birth defects change the shape or function of one or more parts of the body. They can cause problems in overall health, how the body develops, or in how the body works.
As a baby grows, a body tissue called cartilage normally becomes bone in most parts of the body. But if a baby has achondroplasia, cartilage in places like the arms and legs doesn’t turn into bone the way it should. Achondroplasia is a common cause of dwarfism (also called little people), a condition in which a person is very short (less than 4 feet 10 inches as an adult).
Achondroplasia affects about 1 in 15,000 to 1 in 40,000 babies. Most babies born with achondroplasia live a normal life span, but a few may have severe bone problems that can lead to death.
A gene change (also called a mutation) causes achondroplasia. Genes are parts of your body’s cells that store instructions for the way your body grows and works. Genes are passed from parents to children. A gene change is a change to the instructions in a gene. These changes can cause birth defects and other health conditions.
Most babies with achondroplasia are born to parents who don’t have the condition. This happens when there’s a random gene change in either the egg or sperm that join together and create a baby.
If you or your partner has achondroplasia, you can pass it to your baby. If only one of you has the condition, there’s a 1 in 2 chance (50 percent) that your baby can have the condition. If both you and your partner have achondroplasia, there is:
If you or your partner has achondroplasia or you’re the parent of a child with achondroplasia, talk to a genetic counselor about the condition. A genetic counselor is a person who is trained to help you understand about how genes, birth defects and other medical conditions run in families, and how they can affect your health and your baby's health. To find a genetic counselor, ask your provider or contact the National Society of Genetic Counselors.
Before birth, your provider may think your baby has achondroplasia if an ultrasound shows your baby has bone problems, like shortened bones. An ultrasound uses sound waves and a computer screen to make a picture of your baby in the womb.
If the ultrasound shows these bone problems, your provider may recommend a prenatal test called amniocentesis (also called amnio) to confirm that your baby has achrondroplasia. In an amnio, your provider takes some amniotic fluid from around your baby in the uterus. The test checks for birth defects and genetic conditions in your baby.
After birth, your baby’s provider can use X-rays, a physical exam and a blood test to check your baby for achondroplasia.
A person with achondroplasia often has:
People with achondroplasia can have a range of health problems, so it’s important to take your baby to see his health care provider for routine well-baby checkups.
At these checkups, your baby’s provider can compare your baby’s height, weight and head size to those of other babies with achondroplasia. This can help your baby’s provider spot and treat some problems early on.
People with achondroplasia often have these health problems:
Last reviewed April 2013
Dad's exposure to harmful chemicals and substances before conception or during his partner's pregnancy can affect his children. Harmful exposures can include drugs (prescription, over-the-counter and illegal drugs), alcohol, cigarettes, cigarette smoke, chemotherapy and radiation. They also include exposure to lead, mercury and pesticides.
Unlike mom's exposures, dad's exposures do not appear to cause birth defects. They can, however, damage a man's sperm quality, causing fertility problems and miscarriage. Some exposures may cause genetic changes in sperm that may increase the risk of childhood cancer. Cancer treatments, like chemotherapy and radiation, can seriously alter sperm, at least for a few months post treatment. Some men choose to bank their sperm to preserve its integrity before they receive treatment. If you have a question about a specific exposure, contact the Organization of Teratology Information Specialists at www.otispregnancy.org.
The Rh factor may be a problem if mom is Rh-negative but dad is Rh-positive. If dad is Rh-negative, there is no risk.
If your baby gets her Rh-positive factor from dad, your body may believe that your baby's red blood cells are foreign elements attacking you. Your body may make antibodies to fight them. This is called sensitization.
If you're Rh-negative, you can get shots of Rh immune globulin (RhIg) to stop your body from attacking your baby. It's best to get these shots at 28 weeks of pregnancy and again within 72 hours of giving birth if a blood test shows that your baby is Rh-positive. You won't need anymore shots after giving birth if your baby is Rh-negative. You should also get a shot after certain pregnancy exams like an amniocentesis, a chorionic villus sampling or an external cephalic version (when your provider tries to turn a breech-position baby head down before labor). You'll also want to get the shot if you have a miscarriage, an ectopic pregnancy or suffer abdominal trauma.
A cleft lip or cleft palate that extends into the upper gums (where top teeth develop) can cause your baby to have certain dental problems, including:
Every baby with a cleft lip or palate should get regular dental checkups by a dentist with experience taking care of children with oral clefts. Dental problems caused by cleft lip or palate usually can be fixed. If needed, your baby can get ongoing care by a team of experts, including:
See also: Cleft lip and cleft palate
Cleft lip does not cause ear problems.
Babies with cleft palate, however, are more likely than other babies to have ear infections and, in some cases, hearing loss. This is because cleft palate can cause fluid to build up in your baby’s middle ear. The fluid can become infected and cause fever and earache. If fluid keeps building up with or without infection, it can cause mild to moderate hearing loss.
Without treatment , hearing loss can affect your baby’s language development and may become permanent.
With the right care, this kind of hearing loss is usually temporary. Your baby’s provider may recommend:
See also: Cleft lip and cleft palate
Babies with only a cleft lip usually don’t have trouble breastfeeding. Most of the time, they can breastfeed just fine. But they may need some extra time to get started.
Babies with cleft lip and palate or with isolated cleft palate can have:
Most babies with cleft palate can’t feed from the breast. If your baby has cleft palate, he can still get the health benefits of breastfeeding if you feed him breast milk from a bottle. Your provider can show you how to express (pump) milk from your breasts and store breast milk.
Your baby’s provider can help you start good breastfeeding habits right after your baby is born. She may recommend:
Children with cleft lip generally have normal speech. Children with cleft lip and palate or isolated cleft palate may:
Most children can develop normal speech after having cleft palate repair. However, some children may need speech therapy to help develop normal speech.
See also: Cleft lip and cleft palate
The choroid plexus is the area of the brain that produces the fluid that surrounds the brain and spinal cord. This is not an area of the brain that involves learning or thinking. Occasionally, one or more cysts can form in the choroid plexus. These cysts are made of blood vessels and tissue. They do not cause intellectual disabilities or learning problems. Using ultrasound, a health care provider can see these cysts in about 1 in 120 pregnancies at 15 to 20 weeks gestation. Most disappear during pregnancy or within several months after birth and are no risk to the baby. They aren't a problem by themselves. But if screening tests show other signs of risk, they may indicate a possible genetic defect. In this case, testing with higher-level ultrasound and/or amniocentesis may be recommended to confirm or rule out serious problems.
If you didn’t take folic acid before getting pregnant, it doesn't necessarily mean that your baby will be born with birth defects. If women of childbearing age take 400 micrograms of folic acid every day before and during early pregnancy, it may help reduce their baby’s risk for birth defects of the brain and spin called neural tube defects (NTDs). But it only works if you take it before getting pregnant and during the first few weeks of pregnancy, often before you may even know you’re pregnant.
Because nearly half of all pregnancies in the United States are unplanned, it's important that all women of childbearing age (even if they're not trying to get pregnant) get at least 400 micrograms of folic acid every day. Take a multivitamin with folic acid before pregnancy. During pregnancy, switch to a prenatal vitamin, which should have 600 micrograms of folic acid.
Last reviewed November 2012