What are the signs and symptoms of birth defects?
Symptoms of birth defects range from mild to severe. They can affect almost any part of the body like your bones and organs.
During pregnancy, a healthcare provider will use screening tests to look for signs of birth defects. Signs of a birth defect during pregnancy can include:
- Protein levels from a blood test that are higher or lower than expected.
- Extra fluid behind a fetus’ neck during an ultrasound.
- Structural abnormalities of a fetus’ internal organs, like the heart, during a fetal echocardiogram.
Some birth defects won’t be present until a child is born or shortly after birth. Common signs and symptoms of birth defects among infants and toddlers include:
- An abnormal rhythm of their heart.
- Difficulty breathing on their own.
- Not responding to their name being called or loud noises.
- Their eyes don’t follow you or an object in front of them.
- Difficulty feeding.
- Their head, face, eyes, ears or mouth have unique characteristics.
- They don’t meet developmental milestones for their age.
- Irritability.
While this isn’t a complete list of the signs and symptoms of birth defects, contact your child’s healthcare provider if something doesn’t seem right or if you notice any of the signs or symptoms listed above.
What causes birth defects?
There are several possible causes of birth defects, including:
- Genetic changes.
- A side effect of a medication.
- Substance or chemical exposure.
- Pregnancy complications.
These causes occur during fetal development. Many are out of your control and there’s nothing you can do to prevent them.
When a fetus is growing in your uterus, it goes through two major stages of development after conception. The embryo stage occurs during the first 10 weeks after conception. Most of the fetus’ major body systems and organs form during this time. The second, or fetal stage, is the remainder of the pregnancy. This fetal period is a time of organ growth and the growth of the fetus in general.
A developing fetus is most vulnerable to birth defects during the embryo stage when organs are developing. For example, substance or chemical exposure can cause the greatest damage to a fetus between two and 10 weeks after conception.
Medical science has identified the cause of about 30% of birth defects. That means about 70% remain without a straightforward cause. As many as 50% to 70% of birth defects are random, and their cause remains unknown.
Genetics and birth defects
About 20% of birth defects occur as a result of genetic factors.
The average human body cell contains 46 chromosomes, and each chromosome contains thousands of genes. Each gene contains a blueprint that controls the development or function of a particular body part. Among people who have either too many or too few chromosomes, their cells receive a scrambled message on how to develop and function.
Chromosome changes occur when there are:
- Too many chromosomes: Down syndrome is an example of a condition caused by too many chromosomes. During cell division, individuals with Down syndrome have an extra copy of chromosome 21.
- Not enough chromosomes: Turner syndrome is an example of a chromosomal condition where a person is born without part of or missing an entire X sex chromosome.
- Deleted chromosomes: A genetic change can affect the number of chromosomes in your DNA. For example, people diagnosed with Prader-Willi syndrome are missing genetic information on chromosome 15.
- Relocated chromosomes: Chromosomes can move within your DNA to a numbered seat other than their own. This is known as translocation. An example of translocation is rare cases of Smith-Magenis syndrome.
Some birth defects are inherited. This means that you can develop a condition that runs in your biological family. Other conditions occur randomly (sporadically) and you won’t have a history of the condition in your family.
Medications and birth defects
Some medications can have an impact on developing fetuses and can cause birth defects. Common medications that can lead to birth defects include:
- Isotretinoin (Accutane® or Roaccutane®).
- Antiepileptic medications (valproic acid).
- Lithium.
- Warfarin.
If you’re pregnant or plan on becoming pregnant, talk to a healthcare provider about the medications and supplements you currently take and the side effects of medications they prescribe to you. They’ll let you know if it’s safe to continue taking certain medications. Don’t stop taking the medication until your provider approves it.
Substance or chemical exposure and birth defects
Substances and chemicals within a person’s environment can affect the development of a fetus and lead to birth defects. Common substances or chemicals that can lead to birth defects include:
- Alcohol.
- Addictive substances like caffeine, prescription drugs and non-medical drugs.
- Pesticides or herbicides.
- Pollution.
Birth defects are common in certain areas of the world where people used dangerous pesticides and herbicides. An example of this is Agent Orange, an herbicide (plant-killing chemical) used during the Vietnam conflict from 1962 to 1971. This herbicide is no longer available on the market due to its harmful and deadly effects.
Pregnancy complications and birth defects
Some complications that happen during pregnancy can lead to birth defects. These complications are usually outside of the birthing parent’s control and it can be a very emotional experience.
Examples of pregnancy complications that can lead to birth defects include:
- Uterine constraint: The amniotic sack that holds the fetus breaks during pregnancy. This can lead to amniotic band syndrome and possible limb amputations.
- Lack of amniotic fluid: There isn’t enough fluid that surrounds the fetus in your uterus. This can cause pressure on the fetus and can damage its lungs (pulmonary hypoplasia).
- Infection: Certain infections, like toxoplasmosis and cytomegalovirus, can affect a developing fetus.
To prevent these complications, you can talk with a healthcare provider about ways to keep yourself and the developing fetus healthy during pregnancy.
What are the risk factors for birth defects?
Certain factors or health conditions can put you more at risk of having a child with a birth defect. These include but aren’t limited to:
- Diabetes.
- Obesity.
- Age of a birthing parent (over 35 years).
- A genetic condition runs in your biological family history (genetic predisposition).
- Substance-use disorder.
- Taking certain medications.
Your healthcare provider can help you manage any underlying conditions. They can also offer testing to assess your risk of having a child with a genetic condition.
