Imagine the pain and frustration of parents when they come to know about their child born with a birth defect. As the name suggest birth defects are abnormalities that occur while the fetus is still developing in the uterus. The defect can be structural or functional which can cause physical or mental disability when the child is born. Sometimes congenital defect can lead to death of the fetus inside the womb.
It can be a serious birth defect or a minor defect. Some defects can be corrected with the help of surgery such as cleft palate or club foot. However, the child with certain functional defects affecting the nervous system such as Down’s syndrome has to live with this disability throughout his life.
Birth defect can develop due to a flaw in the gene that a fetus inherits from parents.It can also occur as a result of sexually transmitted disease, infections, drug abuse, alcohol, smoking, or intake of certain medication, lack of folic acid during the period of pregnancy.
There are thousands of congenital defects known in medical science. Let us know some of the most commonly encountered birth defects.
Types Of Birth Defects
Birth defects are generally divided into two types, structural and functional.
- Structural birth defects: This type of birth defect is related to physical abnormality in body parts. There may be a structural defect in the organ or a body part such as the heart, limbs, spinal cord, face etc. The best example is spina bifida, defect in the heart valve, cleft palate or cleft lip, abnormality of foot etc.
- Functional birth defect: This type of development birth defect affects various system of the body. Problems related to brain and nervous system includes Down’s syndrome, sensory loss affecting hearing and vision leading to blindness and deafness. It may be related to absence of an enzyme or a chemical in the body causing metabolic disorders such as phenylketonuria, Galactosaemia or Tay-sach’s disease.
Major Causes Of Birth Defects
There are varieties of causes that are known in medical science that may be responsible for birth defect. They may have genetic association or can occur as a result of living unhealthy lifestyle. Intake of certain medications during pregnancy and infections can also cause physical and mental birth defects in the fetus.
Following are some of the risk factors that may cause birth defect in a child:
- Genetic: Family history of birth disorder or a faulty alteration in the genes of parents.
- Infection during pregnancy: Certain infections during pregnancy can affect the developmental growth of the fetus inside the womb. Infections such as sexually transmitted disease, rubella (German measles), toxoplasmosis, etc.
- Lifestyle factors: Smoking, alcohol, abuse of illegal drugs are known to cause birth deformity if taken during pregnancy by the mother.
- Medications: Many medications have side effects. Some of them are known to produce birth defects when they are taken during pregnancy.
- The risk of birth defect increases if pregnancy occurs after the age of 35 years.
Common Birth Defects And Their Symptoms
There are many birth defects; they are either grouped as structural or functional. Most of the birth defects develop in first three months of growth in the womb.
Structural birth defect: In structural defect, a body part is malformed or is absent. Some of the common deformities are:
- Cleft palate or cleft lip: The exact cause is not known, but it is believed to occur due to genetic abnormality or interaction of environmental problem. There is a split in the roof of mouth in cleft palate. Similarly in cleft lips, a split is developed on upper or lower lip. The child finds it difficulty in swallowing liquid and solid. Cleft palate causes nasal twang. They also suffer from frequent infection in ear.
- Heart valve defect: A defect in heart valve can cause breathing and feeding problems in infant. It may also cause blue discoloration of tongue and nail (cyanosis). In adults the symptoms may be breathlessness, fatigue, weight loss, swelling in feet, palpitation, giddiness, chest pain etc.
- Spina bifida: It is an abnormality of neural tube which eventually becomes brain and spinal cord. In this condition there is gap in the vertebra and a tuft of hair in the lower end of spine is seen after birth. Sometimes there is a swelling in the lower spine. Patient may or may not have any symptoms. If present they are involuntary urination and stool or paralysis of legs. In severe cases the condition can be corrected with surgery.
Functional birth defect:
- Down’s syndrome: It is genetically linked condition leading to delay in mental and physical development of the child. The child is born with an extra chromosome 21. Increased age of pregnancy (Mother more than 35 years) increases the risk of Down’s syndrome in the fetus. There may be family history of this syndrome. A baby born with Down’s syndrome has flat face, small head and ears, short neck, slow learning ability, hearing and vision problems, impulsive and poor memory.
- Sickle cell anemia: In this disorder the red cell has distorted shape. It appears as a sickle. Pain, infection, anemia, shortness of breath, skin pallor are common findings in a child suffering from sickle cell anemia.
Phenylketonuria (PKU), turner syndrome, cystic fibrosis etc are some other functional birth defects commonly seen in infants and adults.