A group of experts on fetal alcohol spectrum disorders (FASD) has proposed updated clinical guidelines for diagnosing FASD, which can result when a child is exposed to alcohol during prenatal development. The new guidelines clarify and expand upon the guidelines published by Hoyme and colleagues in 2005, which were the first to help clinicians distinguish among the four distinct subtypes of FASD described by an expert panel organized by the Institute of Medicine. The updated guidelines, developed over one year by a cadre of experts in the field, are based on analysis of characteristics of 10,000 individuals involved in research and epidemiological studies of prenatal alcohol exposure funded by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health.

Photo of pregnant woman

The proposed guidelines include a new definition of documented prenatal alcohol exposure, new guides to evaluating facial anomalies and physical deformities characteristic of FASD, and new information about the extent of cognitive and/or behavioral impairments seen in different FASD subtypes and in children less than 3 years old..

“These new guidelines will be a valuable resource for clinicians to accurately diagnose infants and children who were affected by alcohol exposure before birth,” said NIAAA Director George F. Koob, PhD. “They represent the most data-driven diagnostic criteria for fetal alcohol syndrome and fetal alcohol spectrum disorder produced to date.”

The updated guidelines were developed by researchers funded through NIAAA’s Collaboration on FASD Prevalence (CoFASP), which studies the prevalence of FASD among U.S. school children, and NIAAA’s Collaborative Initiative on Fetal Alcohol Spectrum Disorders (CIFASD), which investigates data-driven methods for diagnosing FASD.  

The paper currently appears online in Pediatrics.

Fetal alcohol spectrum disorders (FASD), the umbrella term for the range of disabilities that can result from prenatal alcohol exposure, represents the leading cause of preventable developmental disabilities in the world. As a result of alcohol exposure in the womb, children can have cognitive deficits and behavioral issues such as attention deficit, poor impulse control, and the inability to regulate mood/behavior.  In addition, some children exposed to alcohol in the womb also have restricted growth and a characteristic pattern of abnormal facial features.  

Recent studies of school-age children suggest that the prevalence of FASD may be higher than previously thought, with 2 to 5 percent of the children in the U.S. showing signs of prenatal alcohol exposure. The American Academy of Pediatrics notes that no amount of alcohol intake during pregnancy can be considered safe; there is no safe trimester to drink alcohol; all forms of alcohol pose a similar risk; and binge drinking poses a dose-related risk to the fetus.

“We’re hopeful that the improved specificity of these guidelines will help clinicians to assess FASD better, thereby leading to early intervention for affected children,” said the study’s first author, Dr. H. Eugene Hoyme, M.D., Chief, Genetics and Genomic Medicine, Sanford Health, and Professor of Pediatrics, Sanford School of Medicine of the University of South Dakota, Sioux Falls, SD. Dr. Hoyme was also the first author on the 2005 guidelines published in Pediatrics.

The authors note that diagnosis of FASD is best accomplished using a multidisciplinary approach. This requires a medical assessment of the child by a pediatrician or clinical geneticist and an expert neuropsychological and behavioral assessment. A skilled interviewer should evaluate the mother to determine the extent/timing of drinking during pregnancy.

Research papers describing the negative effects of prenatal alcohol exposure first appeared in the late 1960’s. In 1996, a panel of experts organized by the Institute of Medicine identified four diagnostic categories within FASD: fetal alcohol syndrome (FAS), for  Individuals with a characteristic pattern of unusual facial features, growth retardation, and central nervous system neurodevelopmental abnormalities, partial fetal alcohol syndrome (PFAS), for individuals who displayed some but not all of the physical and neurodevelopmental characteristics of FAS, alcohol-related neurodevelopmental disorder (ARND), for individuals who demonstrated cognitive or behavioral impairments without the characteristic physical features, and alcohol-related birth defects (ARBD), for individuals with physical malformations associated with prenatal alcohol exposure.

“These four diagnostic categories remain the most apt descriptors of the range of disabilities observed within the continuum of FASD,” said Dr. Kenneth R. Warren, senior advisor to the NIAAA director, who co-authored the updated guidelines. Dr. Warren previously served as NIAAA acting director and deputy director. “We have refined the guidelines to reflect our collective expertise gained through the evaluation of more than10,000 children in domestic and international venues.”

These updates include a more precise definition of documented prenatal alcohol exposure. Exposure can be confirmed when a mother or reliable source reports six or more drinks per week for at least two weeks during pregnancy; three or more drinks per occasion on two or more occasions while pregnant; or has documented alcohol-related social or legal problem during pregnancy, among other indicators.

The proposed guidelines also help pediatricians better diagnose FASD based on typical physical traits. The paper includes a guide for assessing lip/philtrum abnormalities -- children with FAS have a thin upper lip and a flattening of the groove between their nose and upper lip called the philtrum – and a table detailing the scoring system for characteristic physical deformities, based on their prevalence in 370 children with FAS.

The revised guidelines have also been updated to note that all children with FASD, with the exception of those with ARBD alone, will display cognitive or behavioral impairments. Previously, children with typical facial features, growth restriction and microcephaly (small head size) could be given a diagnosis of FASD without demonstrated evidence of neurobehavioral impairment (i.e., behavioral or cognitive abnormalities that cannot be explained by genetics, family background, or environment).

In addition, recurrent seizures or epilepsy has now been included as potential evidence of FAS or PFAS in the updated guidelines, based on evidence that epilepsy is often seen in individuals with FASD.