Fetal Alcohol Syndrome (FAS) Causes, Characteristics and Diagnosis ~ Beauty Care

Fetal Alcohol Syndrome (FAS) Causes, Characteristics and Diagnosis

What is fetal alcohol syndrome?

Although the dangers of alcohol during pregnancy had long been suspected, fetal alcohol syndrome (FAS) was formally described in 1968 by P. Lemoine and colleagues from Nantes (France) in 127 children of alcoholic parents. Their report in a French pediatric journal drew little attention. Focus on FAS only came after it was independently redescribed in 1973 by K.L. Jones and colleagues from Seattle (U.S.) in eight children of mothers with chronic alcoholism. Their report in the British medical journal The Lancet triggered an avalanche of reports of FAS.

Alcohol is capable of causing birth defects. This capability classifies it medically as a teratogen. Alcohol is now recognized as the leading teratogen to which the fetus is likely to be exposed. This applies only to societies in which alcoholic beverages are consumed. In these populations, prenatal alcohol exposure is thought to be the most common cause of mental retardation.

What are the features of fetal alcohol syndrome?

Most of the features of FAS are variable. They may or may not be present in a given child. However, the most common and consistent features of FAS involve the growth, performance, intelligence, head and face, skeleton, and heart of the child.

Growth is diminished. Birth weight is lessened. Retardation of longitudinal growth is evident on the measurements of length in infancy and of standing height later in childhood. The growth lag is permanent.

Performance is impaired. The FAS infant is irritable. The older FAS child is hyperactive. Fine motor skills are impaired with weak grasp, poor eye-hand coordination, and tremors.

Intelligence is diminished. The average IQ is in the 60s. (This level is considered mild mental retardation and qualifies a child in the U.S. as educable retarded.)

The head is small (microcephalic). This decrease may not even be apparent to family and friends. It is evident upon comparison of the child's head circumference to that of a normal child on a growth chart. The usual degree of microcephaly in FAS is classified as mild to moderate. It is primarily due to failure of brain growth. The consequences are neither mild nor moderate.

The face is characteristic with short eye openings (palpebral fissures), sunken nasal bridge, short nose, flattening of the cheekbones and midface, smoothing and elongation of the ridged area (the philtrum) between the nose and lips, and smooth, thin upper lip.

The skeleton shows characteristic changes; abnormal position and function of joints, shortening of the metacarpal bones leading to the fourth and fifth fingers, and shortening of the last bone (the distal phalanx) in the fingers. There is also a small fifth fingernail and a single transverse (simian) crease across the palm.

A heart murmur is often heard and then may go away. The basis is usually a hole between the right and left sides of the heart between the ventricles (the lower chambers) or less commonly, the atria (the upper chambers).

A number of other birth defects can occur in children with FAS. These include such major birth deformities such as hydrocephalus (increased fluid pressure on the brain that may require shunting to relieve the pressure), cleft lip (sometimes with a cleft palate), coarctation (narrowing) of the aorta, and meningomyelocele (spina bifida).

How is the diagnosis of fetal alcohol syndrome made?

The diagnosis of FAS must be based on solid evidence. FAS is a diagnosis of great importance for the entire lifetime of the child, not to speak of its implications for the child's mother and other family members.

To establish a diagnosis of FAS, by convention, the following minimal criteria are met:

small size and weight before and after birth (pre- and postnatal retardation)

specific appearance of the head and face with at least two of the three following groups of sign: small head size (microcephaly), small eyes (microphthalmia) and/or short eye openings (palpebral fissures, and/or underdevelopment of the upper lip, indistinct groove between the lip and nose (the philtrum), and flattened cheekbones

brain involvement with evidence for delay in development, intellectual impairment, or neurologic abnormalities

These criteria are used for the following reasons:

FAS can be difficult to diagnose at and after birth;
FAS can easily be confounded with many other disorders;

there is no one clinical feature that specifically identifies FAS; and

there is no laboratory test to aid in the diagnosis.

Facial features associated with fetal alcohol syndrome

A characteristic pattern of mild facial anomalies associated with FAS include small eye openings, a thin upper lip, or flattened ridges between the base of the nose and the upper lip (a flattened philtrum).

Source: Warren, K.R., and Foudin, L.L. Alcohol-related birth defects-the past, present, and future. Alcohol Research & Health 25(3):153-158, 2001. (Image from NIAAA)

What is the diagnosis "fetal alcohol effects"?

Fetal alcohol effects (FAE) is a softer diagnosis than FAS. The diagnosis of possible FAE is considered when

the person has some signs of FAS;

the person does not meet all of the necessary criteria for FAS; and

there is a history of alcohol exposure before birth.

What problems are peculiar to children with fetal alcohol syndrome?

With time, FAS children tend to have eye, ear, and dental problems. Myopia (nearsightedness) may develop. Problems with the eustachian tube leading to the middle ear set the stage for ear infections. There is frequent malalignment and malocclusion of the teeth. Children with FAS have enough difficulty in life without the additional burden of not being able to see, hear, and eat normally. These deficits should be treated appropriately.

Behavior problems in FAS are manifold, including unpredictable extreme mood swings, impulsiveness, diminished judgment, attention deficit, lack of normal self-discipline, irresponsibility, and difficulty taking social cues.

What causes fetal alcohol syndrome?

The ultimate cause is alcohol intake by the pregnant mother. However, alcohol itself may not be directly responsible for all (or any) of the features of FAS. What may be responsible are byproducts generated when the body metabolizes ("burns") alcohol. The end result is a decrease in the number of brain cells (neurons), abnormal location of neurons (due to disturbance of their normal migration during fetal development), and gross malformation of the brain.

How much alcohol is safe during pregnancy?

Two approaches can be taken to this important question. One is the rigorously scientific approach. It does not go beyond the facts: that most children diagnosed with frank FAS have had overtly alcoholic mothers (who drank at least eight to 10 drinks a day); that children born to women who had four to six drinks a day have had subtle signs of FAS/FAE; that at two drinks a day, the only indisputable effect noted has been subtly lower birth weight; and that below two drinks a day there is no concrete evidence for an effect on the fetus. Thus, from a strictly scientific viewpoint, one cannot say that one drink a day during pregnancy is dangerous to the baby.

The more common approach, and the favored one, is the better-safe-than-sorry approach. This pragmatic position is espoused by public-health experts. Witness the warning label on all alcoholic beverages in the U.S. indicating that "according to the surgeon general, women should not drink alcoholic beverages during pregnancy because of the risk of birth defects." This conservative approach is also followed by most individuals and groups concerned with preventing FAS/FAE. For example, the National Organization on Fetal Alcohol Syndrome states, "No amount of alcohol has been proven safe to consume during pregnancy. FAS and FAE...are 100% preventable when a pregnant woman abstains from alcohol."