Fetal alcohol syndrome
The following criteria must be fully met for an FAS diagnosis:
Growth deficiency: Prenatal or postnatal height or weight (or both) at or below the 10th percentile
FAS facial features: All three FAS facial features present
Central nervous system damage: Clinically significant structural neurological, or functional impairment
Prenatal alcohol exposure: Confirmed or Unknown prenatal alcohol exposureFetal alcohol syndrome (FAS) is the first diagnosable condition of FASD that was discovered. FAS is the only expression of FASD that has garnered consensus among experts to become an official ICD-9 and ICD-10 diagnosis. To make this diagnosis or determine any FASD condition, a multi-disciplinary evaluation is necessary to assess each of the four key features for assessment. Generally, a trained physician will determine growth deficiency and FAS facial features. While a qualified physician may also assess central nervous system structural abnormalities and/or neurological problems, usually central nervous system damage is determined through psychological, speech-language, and occupational therapy assessments to ascertain clinically significant impairments in three or more of the Ten Brain Domains. Prenatal alcohol exposure risk may be assessed by a qualified physician, psychologist, social worker, or chemical health counselor. These professionals work together as a team to assess and interpret data of each key feature for assessment and develop an integrative, multi-disciplinary report to diagnose FAS (or other FASD conditions) in an individual. Partial FAS
Partial FAS (pFAS) was previously known as atypical FAS in the 1997 edition of the "4-Digit Diagnostic Code".
People with pFAS have a confirmed history of prenatal alcohol exposure, but may lack growth deficiency or the complete facial stigmata. Central nervous system damage is present at the same level as FAS. These individuals have the same functional disabilities but "look" less like FAS.The following criteria must be fully met for a diagnosis of Partial FAS:
Growth deficiency: Growth or height may range from normal to deficient
FAS facial features: Two or three FAS facial features present
Central nervous system damage: Clinically significant structural, neurological, or functional impairment in three or more of the Ten Brain Domains
Prenatal alcohol exposure: Confirmed prenatal alcohol exposure

Fetal alcohol effects
Fetal alcohol effects (FAE) is a previous term for alcohol-related neurodevelopmental disorder and alcohol-related birth defects. It was initially used in research studies to describe humans and animals in whom teratogenic effects were seen after confirmed prenatal alcohol exposure (or unknown exposure for humans), but without obvious physical anomalies. Smith (1981) described FAE as an "extremely important concept" to highlight the debilitating effects of brain damage, regardless of the growth or facial features. This term has fallen out of favor with clinicians because it was often regarded by the public as a less severe disability than FAS, when in fact its effects can be just as detrimental. Alcohol-related neurodevelopmental disorder
Alcohol-related neurodevelopmental disorder (ARND) was initially suggested by the Institute of Medicine to replace the term FAE and focus on central nervous system damage, rather than growth deficiency or FAS facial features. The Canadian guidelines also use this diagnosis and the same criteria.