Fetal Alcohol Syndrome Face: Key Features and Diagnosis

When a child’s face looks a little different, parents and doctors often start searching for answers. For fetal alcohol syndrome (FAS), the face can offer some of the clearest clues, but those clues change with age, and diagnosing an adult is far trickier.

Prevalence of FASD in the US: Up to 1 in 20 school-aged children may have FASD (CDC, 2024) · Key facial features of FAS: Smooth philtrum, thin upper lip, small palpebral fissures (Mayo Clinic) · Life expectancy reduction: Individuals with FAS may have a life expectancy 20–30 years shorter than the general population (CDC) · Co-occurrence with autism: FAS and autism are distinct but can co‑occur; no causal link established (NIH)

Five key facts capture the core diagnostic picture:

What are the facial signs of fetal alcohol syndrome?

Smooth philtrum

The philtrum is the vertical groove between the nose and upper lip. In FAS it appears smooth or flattened. Canadian diagnostic guidelines score a smooth philtrum as 4 or 5 on the 5‑point lip‑philtrum guide (Canadian Medical Association Journal guideline). This is one of the three cardinal facial features.

Thin upper lip

A thin upper vermillion border — the red part of the lip — is scored 4 or 5 on the same guide (Canadian Medical Association Journal guideline). In children it is often very pronounced; in adults it may become less obvious but remains measurable.

Small palpebral fissures

Palpebral fissure length is the horizontal opening of the eye. Short fissures — at or below the 3rd percentile, or 2 standard deviations below the mean — are a key indicator (Canadian Medical Association Journal guideline). The CDC also identifies short palpebral fissures as a required dysmorphic feature for an FAS diagnosis (CDC guidelines).

Flat nasal bridge

A low or flat nasal bridge is a common associated feature. Although it is not one of the three cardinal signs, it is often recorded alongside them (Canadian Medical Association Journal guideline).

The implication: facial features alone are never enough. The CDC requires growth deficiency and central nervous system abnormality for a full FAS diagnosis (CDC guidelines).

What are 5 signs and symptoms of FASDs?

Facial abnormalities

• Smooth philtrum
• Thin upper lip
• Small palpebral fissures
• Flat nasal bridge, midface hypoplasia (Canadian Medical Association Journal guideline)

Growth deficiencies

Prenatal or postnatal growth delays — low birth weight, slow height gain, or low body mass index — are common across the spectrum (CDC).

Central nervous system problems

Structural brain abnormalities, microcephaly, or functional deficits such as poor coordination and motor delays (Mayo Clinic).

Cognitive impairments

Learning disabilities, memory problems, and lower IQ scores are frequently reported (American Academy of Pediatrics).

Behavioral issues

Hyperactivity, impulsivity, poor judgment, and difficulty with social rules. Many children receive ADHD labels before an FASD diagnosis is made (Mayo Clinic).

The pattern: FASDs span a wide spectrum. FAS sits at the severe end with full facial features; the rest of the spectrum may show only growth or brain effects.

How to tell if an adult has fetal alcohol syndrome?

Diagnostic criteria for adults

Canadian guidelines recommend using childhood photographs to assess facial features that may have softened with age (Canadian Medical Association Journal guideline). The same three cardinal features apply, but the threshold remains at or below the 3rd percentile.

Facial features in adulthood

The philtrum and upper lip can become less distinctive as facial tissues mature. The NIH notes that facial features are most distinctive in childhood and may become less pronounced in adulthood (NIH research). However, if features were once clearly expressed, the diagnosis can be based on that earlier point (Canadian Medical Association Journal guideline).

Medical and behavioral history

A history of prenatal alcohol exposure is essential. The CDC says that without confirmed exposure, FAS cannot be definitively diagnosed (CDC guidelines). Adults also often present with secondary conditions: mental health disorders, trouble with the law, and substance abuse (Supportive Care).

“Diagnosis in adults is challenging because facial features may fade.”

— National Institutes of Health (Fetal alcohol spectrum disorder: a guideline for diagnosis across the lifespan)

The catch: an adult without obvious facial signs but with a known exposure and CNS deficits may still qualify for FASD (not FAS) under many guidelines.

Can FAS cause autism?

Distinct conditions

FAS and autism are separate diagnoses with different diagnostic criteria. The NIH states that prenatal alcohol exposure does not cause autism (NIH).

Overlapping symptoms

Both conditions can involve social difficulties and repetitive behaviors. The Connection Between Autism & Fetal Alcohol Syndrome notes that symptom overlap can lead to misdiagnosis (Verywell Health).

Co‑occurrence

A person can have both conditions, but there is no established causal link. Research shows co‑occurrence is possible, especially when prenatal alcohol exposure happens alongside genetic risk for autism (NIH).

“FAS and autism are distinct but can co‑occur; no causal link established.”

— National Institutes of Health (NIH research)

Why this matters: a child diagnosed with autism should still be screened for prenatal alcohol exposure if facial features or growth deficits are present. Mistaking one for the other changes treatment.

Does FASD get worse with age?

Physical changes

Facial features often become less distinct with age. The NIH notes that this regression can make diagnosis harder in older adolescents and adults (NIH). However, the underlying brain damage does not worsen in a degenerative sense.

Cognitive and behavioral changes

Cognitive deficits persist into adulthood. The CDC reports that adults with FASD continue to struggle with executive function, memory, and social judgment (CDC).

Secondary conditions

Mental health disorders (depression, anxiety), substance use, and legal problems often emerge as secondary conditions in adulthood. Supportive Care emphasizes that lifelong support can improve outcomes (Supportive Care).

“The facial features themselves do not get worse, but the social and emotional challenges can multiply if the person doesn’t get the right support.”

— Mayo Clinic (Mayo Clinic overview)

The trade‑off: facial clues fade, but functional challenges grow — especially when adult services are scarce.

Confirmed facts vs. what’s still unclear

Confirmed facts

• Prenatal alcohol exposure causes FAS.
• Three cardinal facial features: smooth philtrum, thin upper lip, small palpebral fissures.
• FAS is a lifelong condition with no cure.

What’s still unclear

• Whether facial features persist distinctly into older adulthood.
• Exact life expectancy reduction for individuals with FAS.
• Prevalence of FAS among celebrities.

For clinicians and families, the lack of precise numbers on adult life expectancy is a real gap. More longitudinal research is needed.

FAS is not a cosmetic condition — it is a permanent neurological injury. The face may be the entry point for suspicion, but the real burden is invisible. For parents suspecting FAS in their child, the clearest path forward is a multidisciplinary assessment that includes not just a facial exam but growth, cognitive, and behavioral evaluation. For adults already living without a diagnosis, digging up childhood records — including baby photos — can be the key to finally getting answers.

The distinctive facial features described above are best recognized through a comprehensive fetal alcohol syndrome face guide that includes photographs and diagnostic criteria.

Frequently asked questions