Birth defects in children can be caused by genetic, environmental or parental factors. — Positive Parenting
A pivotal moment in the parenting journey is the arrival of your child.
However, the challenges posed by birth defects and complications can significantly impact many families.
Therefore, it is important for parents to understand the different types of birth defects and preventive measures.
A birth defect refers to any malformations or abnormalities that occur during pregnancy.
In most cases, birth defects are detected during pregnancy, at the time of birth or during the early childhood phase.
Birth defects can either be structural (affect the physical structure or form of a body part or organ) or functional (affect the metabolic functions of a body system, organ or tissue).
Two examples of structural birth defects are cleft lip and/or palate, and neural tube defects.
A cleft lip or palate is a malformation of the lip or mouth that occurs during foetal development.
The cause is unknown, although it is believed to be influenced by genetic and environmental factors.
Neural tube defects are a group of conditions where there is a malformation of the neural tube that occurs during foetal development.
Insufficient folic acid in the mother is the cause of this condition.
Two examples of functional birth defects are phenylketonuria and muscular dystrophy.
Phenylketonuria is a metabolic disorder that prevents the breakdown of the amino acid phenylalanine, causing it to build up in the body and result in serious complications like intellectual disability, behavioural problems and seizures.
Muscular dystrophy is a group of degenerative conditions that cause muscle weakness and loss of muscle mass over time.
Both conditions are genetic in nature.
Causes and risk factors
There are a number of causes and risk factors for birth defects.
As seen in the examples above, certain genetic conditions can cause birth defects.
These conditions may affect:
- Specific parts of genes
Small changes in the DNA (deoxyribonucleic acid), such as microdeletions or microduplications, can affect small segments of genetic material.
This can result in intellectual disability, autism spectrum disorders, dysmorphic features and multiple congenital anomalies.
- Entire chromosomes
Some genetic conditions cause changes to entire chromosomes.
This can result in conditions like Down syndrome, which involves having an extra copy of an entire chromosome.
- Single gene disorders
This is caused by variations (or mutations) in the DNA sequence of a specific gene.
The DNA changes affect the product that the gene codes for – usually a protein – causing it to be altered or missing.
Examples of single-gene disorders include cystic fibrosis, haemochromatosis, Tay-Sachs disease and sickle cell anaemia.
Some factors arise from the condition of the parents themselves. These include:
- Having certain medical conditions
Some medical conditions, such as being obese or having uncontrolled diabetes (before and during pregnancy), can increase the risk of birth defects.
- Older age
Conceiving a child at an older age increases the risk of birth defects.
This is because the risk of chromosomal abnormalities increases with age.
- Family history of birth defects
If someone in either parent’s family has a birth defect, this can increase the risk of the child having a birth defect.
Environmental factors can also play a role in birth defects, e.g.:
- Maternal infections, e.g. syphilis, rubella, Zika, cytomegalovirus, etc.
- Radiation exposure
- Exposure to toxic pollutants, e.g. mercury, lead, etc.
- Exposure to certain drugs/substances, e.g. recreational drugs, isotretinoin (a drug used to treat severe acne), certain blood pressure medications, alcohol, tobacco, etc.
Prevention
Here are some ways you can help to prevent those birth defects that are avoidable:
Ensure that you attend prenatal check-ups at the clinic.
This can include getting antenatal tests throughout your pregnancy journey (during different trimesters) in order to monitor and check on the health of your little one to see if he/she is developing healthily.
Such tests may include screening tests (to evaluate the risk of certain birth defects) or diagnostic tests (to confirm the presence of specific birth defects).
Take the right steps to monitor and manage any chronic condition (e.g. diabetes, hypertension, etc.) that you have, as it may be a risk factor for certain birth defects.
It is also important to achieve and maintain a healthy weight during pregnancy, especially in those who are obese, as this may also increase the risk of birth defects.
Eat a healthy diet that includes a wide variety of whole foods (e.g. fruits, vegetables, etc).
Ensure an adequate intake of vitamins and minerals to prevent certain birth defects.
For example, taking folic acid supplements (4-5mg daily) is vital to prevent neural tube defects.
Certain maternal infections may cause birth defects, but some of them can be prevented with vaccinations.
For example, the rubella vaccine can help prevent rubella virus infections, which can result in the death of the fetus or damage to the baby’s eyes, ears or heart, among others.
Avoid the consumption of, or exposure to, harmful substances like alcohol, tobacco and environmental pollutants (e.g. lead, mercury, etc).
Speak with your doctor to learn more about the medications to avoid during pregnancy as some can cause birth defects.
If you have a family history of birth defects, speak with your doctor to learn more about genetic counselling and the various testing options available.
It is important for parents to understand the risk of birth defects.
By practising early preventive measures, parents can ensure a healthy pregnancy and the safe arrival of their little one.
It is also crucial for parents to speak with a healthcare professional for more information on birth defects.
Dr Yap Moy Juan is a consultant obstetrician and gynaecologist. This article is courtesy of the Malaysian Paediatric Association’s Positive Parenting programme in collaboration with expert partners. For further information, please email starhealth@thestar.com.my. The information provided is for educational and communication purposes only, and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
