Fetal alcohol syndrome (FAS) refers to a set of physical and mental defects that are caused by a mother consuming alcohol during pregnancy. The severity of FAS symptoms varies from child to child, but all defects that do occur are irreversible.

No amount of alcohol has been shown to be safe to consume during pregnancy and anyone who drinks during this time places their baby at risk of developing FAS. A woman’s child is at risk of FAS at any point during her pregnancy, as development is ongoing throughout the whole of the gestation period.

Worldwide, FAS is one of the most common causes of impaired intellectual ability and in the United States, the condition is thought to cause intellectual disability in up to 2 in every 1,000 babies born. The number of FAS cases diagnosed in England has tripled since records of the syndrome began 16 years ago. In 2012, 252 children were diagnosed with the syndrome compared with 89 in 1997. This 2012 figure was also up by 37%, compared with numbers in 2009.

Experts say the rise in figures represents an improvement in the ability to diagnose this condition, but it also reflects the ongoing failure to address and solve alcohol abuse.

Pathology

FAS is caused by alcohol in the mother’s bloodstream crossing the placenta and reaching the fetus. The blood alcohol concentration in the developing fetus is much higher than in the mother’s blood because the fetus metabolizes alcohol so much more slowly than the mother does. In the fetus, alcohol impairs the delivery of oxygen and nutrition to developing tissues and organs. The brain, heart, bones and central nervous system may all be affected if a mother drinks during the first trimester, when these parts of the fetus are undergoing key stages in development. Damage to the baby may also be caused by drinking at any other point throughout the pregnancy.

Symptoms

The signs and symptoms of FAS vary widely and include a mixture of physical, cognitive and behavioural difficulties that affect the child’s ability to function on a daily basis and cope with everyday life.

Physical defects

Some of the physical defects typically seen in children with FAS are described below.

• Distinctive facial features include wide-set eyes; absence of the groove between the nose and upper lip (the philtrum); a thin upper lip and an upturned nose.
• The limbs, joints, and fingers may be deformed
• Delayed growth during and after birth
• Hearing and visual disturbances
• Heart, kidney and bone defects
• Small head and brain size (microcephaly)

Central nervous system defects

One of the main effects of FAS is damage to the central nervous system, particularly the brain. The development of certain brain parts may have been disrupted by exposure to the alcohol, which can lead to various problems such as the following:

• Poor memory
• Attention deficit disorder
• Intellectual disability and learning disability
• Difficulty processing information
• Hyperactivity
• Poor cognitive skills such as reasoning or problem solving
• Poor judgement skills and difficulty evaluating consequences of choices
• Rapidly changing emotional state

Effects on behavior

The effects FAS has on physical features and the central nervous systems can lead to behavioral issues, as children find it difficult to cope and interact with others. Some of the problems these children typically face are described below:

• Poor social skills and difficulty getting on with other children
• Difficulty in school
• Difficulty switching between tasks and dealing with change
• Impulsivity and poorly controlled behavior
• Difficulty planning and achieving a goal

Diagnosis

FAS can be difficult to diagnose because there is no blood test for the condition and the symptoms often overlap with those of other conditions such as ADHD and Williams Syndrome. However, when diagnosing this syndrome, doctors will usually look for the following signs and symptoms:

• Abnormal facial features (see above)
• Below average weight and/or height
• Central nervous system disorders (see above)
• History of maternal intake of alcohol during pregnancy

Treatment

There is no cure for FAS and the defects that these children are born with affect them for their entire lives. However, early intervention services are available to help children with the condition and try to prevent some of the problems that can develop. These interventions typically include:

• Speech and hearing therapy
• Physical therapy to aid walking, for example
• Services in schools for children experiencing learning or behavioral issues
• Counseling for parents and other family members to help them cope with associated problems such as behavioral issues
• Medication to relieve certain symptoms
• Medical intervention to address health problems such as a heart defect
• Treatment for alcoholism to help the mother improve her parenting and prevent the likelihood of any further pregnancies being affected by the condition

Further Reading

• All Fetal Alcohol Syndrome Content
• Fetal Alcohol Spectrum Disorders FASD Treatments

Written by

Sally Robertson

Sally has a Bachelor's Degree in Biomedical Sciences (B.Sc.). She is a specialist in reviewing and summarising the latest findings across all areas of medicine covered in major, high-impact, world-leading international medical journals, international press conferences and bulletins from governmental agencies and regulatory bodies. At News-Medical, Sally generates daily news features, life science articles and interview coverage.