Down syndrome is a genetic disorder that causes physical, developmental and intellectual impairment. Not all characteristics are present in all people with Down syndrome and levels of impairment can vary greatly.…
Foetal alcohol syndrome
What is foetal alcohol syndrome?
Foetal alcohol syndrome is part of a group of conditions, in which a baby develops long-term complications due to exposure to alcohol, from the mother drinking during pregnancy. These complications include intellectual, physical and behavioural issues.
Foetal alcohol syndrome is at the extreme end of a class of conditions known as foetal alcohol spectrum disorders. Globally, these disorders are a significant cause of intellectual impairment.
Causes
The time spent in the uterus is a unique period in human life. During these months, the unborn baby must build itself from a single cell to a fully developed baby. The body undergoes many growth and development processes that will never be repeated later in life. These processes rely on the accurate action of a small number of developmental genes and signal molecules, which have a major effect on the overall development of the unborn baby.
When a pregnant woman drinks alcohol, it passes via her bloodstream to the unborn baby. It then has a profound effect on the operation of genetic mechanisms that are crucial to the development of the brain and nervous system. This may lead to the baby being born with a range of disorders, from mild to severe.
The risk to an unborn baby of developing a foetal alcohol spectrum disorder is usually higher the earlier and the more frequently in a pregnancy its mother drinks alcohol. However, even with heavy maternal alcohol consumption, a baby may not develop an obvious foetal alcohol spectrum disorder. Researchers do not know why some babies exposed to seemingly similar levels of alcohol in the uterus develop a disorder while others do not.
A lower 'safe' level of consumption is unknown, so guidelines in many countries, including Australia, recommend that a woman who is pregnant (or who believes she might be pregnant) stops consuming alcohol completely until the baby is born. This 'safe rather than sorry' approach is likely to continue until more definitive research and evidence is available. However, it is very difficult to give a good estimate of the overall influence of alcohol on foetal development. Signs of problems related to alcohol exposure are not always evident at birth and may not be suspected until years later. Even then, it often cannot be proven that a problem in a child's health or behaviour was actually caused by alcohol exposure in the uterus years before. Self-reporting of current or past alcohol consumption is not always accurate by people while pregnant or otherwise, so research and evidence can be hard to gather and interpret.
Genetic
Related to genes, the body's units of inheritance or origin.
Nervous system
The extensive network of cells and structures that is responsible for activating and coordinating the body's functions, sensory input and cognition.
Uterus
The hollow organ of the female reproductive system that is responsible for the development of the embryo and foetus during pregnancy. Also known as the womb.
Risk factors
Alcohol consumption
The risks to an unborn baby from the mother's alcohol consumption are related to three main factors:
- Quantity - how much alcohol the mother drinks;
- Timing - at what point in the pregnancy she drinks, and;
- Frequency - how often she drinks.
The risk of alcohol-related damage to the baby increases the more, the earlier and the more frequently the mother drinks. Maternal binge drinking is particularly risky.
Additional risk factors
Other factors that can affect a baby's chances of developing foetal alcohol syndrome include:
- Maternal smoking and use of recreational drugs;
- Maternal stress and anxiety during pregnancy, or poor prenatal care;
- Low socio-economic status - this is linked to a higher incidence of foetal alcohol syndrome, and;
- Genetic susceptibility - some people and some populations have been found to be genetically more susceptible to foetal alcohol syndrome than others.
Genetic
Related to genes, the body's units of inheritance or origin.
Stress
The word ‘stress’ can have a variety of meanings, but generally describes the physical and mental responses of the body to a demand placed upon it. Often used to describe conditions where the demand is high or unable to be resolved and creates anxiety and tension.
Types
Foetal alcohol syndrome is the most extreme of the foetal alcohol spectrum disorders. The other disorders in this group include:
- Partial foetal alcohol syndrome - people showing only some of the diagnostic signs of foetal alcohol syndrome;
- Alcohol-related neurodevelopmental disorder (ARND) - problems in the central nervous system, and;
- Alcohol-related birth defects (ARBD) - physical problems in the heart, bones, kidneys, vision and hearing.
Central nervous system
The part of the body's nervous system that includes the brain and the spinal cord.
Kidneys
A pair of organs responsible primarily for regulating the water balance in the body and filtering the blood.
Nervous system
The extensive network of cells and structures that is responsible for activating and coordinating the body's functions, sensory input and cognition.
Signs and symptoms
At birth
A baby born with foetal alcohol syndrome may have some or all of the following symptoms:
- Small birth size and weight;
- Small head;
- Problems with muscle control and suckling;
- Heart defects, and;
- Kidney problems.
Facial features
Babies born with foetal alcohol syndrome share some distinctive facial features, including:
- Small head;
- Wide-set eyes, small eye openings;
- Small upper jaw;
- Thin upper lip;
- Area between nose and upper lip (philtrum) is flat and long;
- Flat mid-face;
- Short nose, and;
- A smooth ridge between nose and mouth.
In later life
As the baby grows, some or all of the following symptoms may appear:
- Thinking and learning disabilities;
- Cognitive defects, low intelligence;
- Behavioural problems, poor social skills, criminal or inappropriate behaviour;
- Emotional disorders, rapid mood changes;
- Poor memory skills;
- Speech delays;
- Attention deficits, difficulty with processing information, reasoning, planning and problem solving;
- Hyperactivity;
- Sleep problems;
- Vision and hearing difficulties;
- Poor coordination;
- Tremors, and;
- Balance difficulties.
These problems can remain for a person's lifetime.
Methods for diagnosis
There is no single test for foetal alcohol syndrome. A diagnosis of foetal alcohol syndrome will be made by the severity of symptoms, including:
- The distinctive facial features;
- Brain abnormality or mental problems, and;
- Growth deficits.
If the condition is diagnosed early on in the child's life, early intervention strategies can be used to better effect.
Brain imaging tests
In recent years, several kinds of brain imaging techniques such as magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) scans are being used to identify and classify defects in the brains of people with foetal alcohol syndrome.
Early intervention
A program of services designed to help babies and young children who have, or are at risk of having, developmental delays or disabilities.
Magnetic resonance imaging
A type of imaging that uses a magnetic field and low-energy radio waves, instead of X-rays, to obtain images of organs.
Positron emission tomography
During positron emission tomography (PET) scan, an injection with a radioactive label is administered and then combined with a computerised tomography (CT) scan to produce functional images.
Functional magnetic resonance imaging
A technique that enables measurement of the brain activity from magnetic resonance imaging of the changes in the blood flow.
Treatment and prognosis
There is no cure for foetal alcohol syndrome. By the time the baby is born, the effects of the syndrome are already in place and cannot be reversed. They are different for every person, but these effects can last a lifetime.
Professional treatment by healthcare professionals (occupational therapists, speech pathologists, psychologists) and a stable, nurturing social environment can help reduce and manage the effects of foetal alcohol syndrome to some degree.
Some medications can help manage behavioural and other problems caused by foetal alcohol syndrome. The specific course of medication varies from case to case.
Prevention
On an individual level, foetal alcohol syndrome can be prevented by not consuming any alcohol during pregnancy. A 'safe' level of alcohol consumption in pregnancy is unknown.
On a wider level, prevention of foetal alcohol syndrome focuses on:
- Educating women about known and potential risks of alcohol consumption during pregnancy so they can make informed choices;
- Encouraging women to seek assistance preferably before they conceive if they have trouble with alcohol, and;
- Providing support for pregnant women who are at risk of drinking during pregnancy and may be facing difficult circumstances.