What is a birth defect?
A birth defect is an abnormal condition which may also be called a “congenital” defect or abnormality. A birth defect develops during gestation, while the fetus is growing inside of the womb or uterus. Birth defects can result in malformation or deformity, affect function of body processes or increase the chance of miscarriage or death. Some birth defects are inherited, while others are caused by outside conditions such as medications or disease.
What are the causes of birth defects
There are about 4,000 types of birth defects which range in severity, effect, and cause. While some birth defects are a result of genetics and cannot be predicted, others are preventable. Certain behaviors and other factors are known to increase the risk of having a birth defect.
Risk factors include:
Consumption of alcohol, tobacco, and drugs of abuse – Women who drink alcohol, smoke tobacco or abuse illegal drugs will increase the risk of birth defects. Alcohol is known to cause fetal alcohol syndrome, smoking contributes to low birth weight and other conditions and illegal drugs can cause a wide range of fetal abnormalities.
Medical disorders or conditions – Women who have certain conditions may increase the risk of birth defect. Known risks include women with diabetes, thyroid conditions and infections like strep B, cytomegalovirus, rubella and others.
Medications – Certain medications are known to increase the risk of birth defects. Certain medications should not be used during pregnancy, while others may be given if the benefits outweigh the risks. In many cases, however, a drug may be considered safe when first introduced but birth defects in the population begin to appear after a period of time.
Genetics and family history – Some birth defects are more likely to occur in certain families and are passed down from generation to generation. Common heritable diseases include cystic fibrosis, hemophilia, skeletal abnormalities, and many other conditions. Families with a history of genetic birth defects may wish to consider genetic counseling to determine the risk of future pregnancies.
Maternal age – Women who are older than the age of 34 when a child is conceived are more likely to have a child with a birth defect. This includes a higher than normal risk of genetic conditions such as Down Syndrome but also includes an increased risk of medical problems and pregnancy complications which can also increase birth defect risk.
Types of birth defects
Birth defects can be categorized by the type of condition and what part of the body is affected. Birth defects may be considered structural, functional or both.
Structural birth defects occur when a part of the body is malformed or missing. Structural defect examples include spina bifida, cleft palate, abnormal limb, and cardiac septal defects.
Functional birth defects affect how a body system works. It may be related to an organ system like the lungs or heart and may affect intellectual or cognitive development. Functional birth defects are usually further categorized into groups based on the body system affected by the disorder such as:
- Neurological – disorders affecting the brain or the nervous system. This may include seizure disorders, language or cognitive development and mobility issues. Down Syndrome is an example of a birth defect which affects cognitive development, though it also affects many other systems.
- Sensory – birth defects which affect any of the senses but mainly include blindness and deafness, both partial and total.
- Metabolic – disorders which affect how the body functions in terms of metabolic processes including digestion, drug metabolism, and energy production. Examples of metabolic disorders include hypothyroidism and phenylketonuria (PKU) disease.
- Degenerative – disorders which may not be obvious at birth but will become worse over time. Examples include muscular dystrophy and cystic fibrosis.
Detection and diagnosis of birth defects
Many birth defects are apparent at birth, particularly when they involve a structural abnormality such as cleft lip, Down Syndrome, or limb disorders. Others may become apparent within the first year when the child is not developing properly and may require additional testing to diagnose and treat the disorder. In certain cases, specific birth defects may be identified and even corrected before birth, while still in utero.
Treatment of birth defects
Treatment of a birth defect will depend on the type and severity of the condition. Some structural defects such as cleft palate or lip and certain congenital heart defects may be corrected with surgery. In other cases, conditions may be treatable with medications or managed through other means including occupational or physical therapy. Some birth defects however, are not considered treatable and counseling of family members or caregivers may be warranted.
Birth defect prevention
Some types of birth defects, particularly those related to genetics, cannot be prevented but some are a direct result of events that occur during pregnancy. Steps can be taken to help decrease the risk of avoidable birth defects. In the U.S., the Centers for Disease Control and Prevention or CDC developed “PACT” as a way to help reduce the risk of birth defects.
PACT stands for Plan ahead, Avoid harmful substances, Choose a healthy lifestyle and Talk to your doctor.
P – Plan ahead. Women who plan to become pregnant should be eating a healthy diet and are recommended to take a daily folic acid supplement. Folic acid can help to prevent neural tube deficit birth defects like spina bifida. Women who are considering pregnancy and those who are pregnant should avoid places where illness like Zika virus are prevalent.
A – Avoid harmful substances. Women who are pregnant should avoid consuming alcoholic beverages, smoking, and drugs of abuse. A developing fetus is exposed to the same substances a mother consumes or ingests. Alcohol consumption is known to cause fetal alcohol syndrome while smoking and drug abuse contributes to a number of health conditions.
C – Choose a healthy lifestyle. In addition to good nutrition and appropriate exercise, women who are pregnant should ensure that their blood sugar levels are tested and remain under control. Women who are obese and those who have high blood sugar levels are more likely to have difficulty during pregnancy and delivery and may have an increased risk of complications. Following dietary and lifestyle guidelines can help reduce the risk to both mother and infant.
T – Talk to your doctor. Getting early and adequate prenatal care is an important way to reduce the risk of birth defects. Women who are pregnant should discuss any medications they plan to take during pregnancy and should address any medical issues they are experiencing. Certain medications should not be taken during pregnancy, while others may be used if the benefits outweigh the risks.
When birth defects occur
Some birth defects are unavoidable but others may have been prevented. One common cause of birth defects which should have been preventable is the use of certain medications. Examples of medications which have been linked to birth defects include Zofran (ondansetron) and Paxil (paroxetine).
Zofran (ondansetron) was developed by GlaxoSmithKline and was prescribed to many women as an “off-label treatment” for morning sickness. It had not been tested on pregnant women but the company may have known that it was unsafe. Zofran use is linked to birth defects including heart defects, cleft palate, and kidney problems. Hundreds of families have filed lawsuits against GSK for Zofran birth defects.
Paxil (paroxetine) is also marketed by GlaxoSmithKline and is used for depression. It was considered “safe” for use during pregnancy but many women who took the medication had children who were born with cardiovascular or lung defects or later developed autism. A large number of families have filed lawsuits against GSK for Paxil birth defects.
Other medications which may have caused birth defects include:
- SSRI antidepressants
- Seizure medications
- NSAID pain relievers
Women who are pregnant or who plant to become pregnant should discuss all of their medications with a physician.
Family members or caregivers of children born with a preventable birth defect may be eligible for compensation for medical costs and other damages and should consider seeking legal advice.