Despite fetal alcohol syndrome (FAS) developing in fetuses, doctors cannot reliably use ultrasound to diagnose the condition. Diagnosis only occurs after birth.

FAS is the most serious form of fetal alcohol spectrum disorder (FASD).

A fetus can develop FASD in the womb when a pregnant individual drinks alcohol while pregnant. This alcohol exposure can cause problems with growth, learning, and behavior.

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A nurse and patient studying an ultrasound image of a fetus. -1Share on Pinterest
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Ultrasounds are imaging techniques. Doctors can use them to create images of a fetus as it develops within the womb.

A 2016 studyTrusted Source investigated whether second-trimester ultrasounds can help detect FASD. The research found that ultrasounds do not allow doctors to diagnose FASD reliably at this point in the pregnancy.

The authors suggest that ultrasounds may one day help with diagnosing FASD if doctors use them in combination with other techniques. However, scientists have not tested this suggestion.

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According to a 2019 reviewTrusted Source of the scientific literature, there are several diagnostic criteria for FASD:

Doctors can assess these criteria using observation, imaging techniques, and tests.

In the case of FAS, doctors mustTrusted Source find evidence of facial or brain abnormalities, inhibited growth, and an unusual facial shape or features. While other characteristics might be present, they are not necessary for an FAS diagnosis.

FASDs are incurable conditions. However, some treatment options can help manage symptoms. These interventions can vary from individual to individual.

For instance, the Centers for Disease Control and Prevention (CDC)Trusted Source explains that the following medications can be useful for some people with FASD:

Behavior and education therapies can also help. These might include:

  • training in social skills
  • specialized help with mathematics
  • programs that teach planning, organizing, and understanding other people

Parents or caregivers of children with FASD may also benefit from learning specific parenting techniques.

As a 2018 reviewTrusted Source explains, FAS is a preventable condition, so avoiding alcohol during pregnancy will prevent FAS.

Alcohol consumption during pregnancy can also increase the riskTrusted Source of the following:

Anyone with concerns about alcohol consumption during their pregnancy should speak with a doctor.

Several organizations may help people affected by FAS.

For instance, FASD United provides advice and referrals for those with FASD as well as their caregivers. It can also advise people who have an alcohol use disorder and are pregnant or intend to be.

These individuals may also benefit from FindTreatment.gov, a resource that can help them find ways to manage their alcohol use disorder.

What can be mistaken for fetal alcohol syndrome?

According to a 2023 reviewTrusted Source, fetal alcohol syndrome can present similarly to several conditions. These include Dubowitz syndrome, toluene embryopathy, and maternal phenylketonuria.

At what stage of pregnancy does alcohol affect the baby?

As a 2023 review Trusted Sourceexplains, alcohol intake can affect the baby at any stage of pregnancy. Drinking alcohol at any stage of pregnancy poses a risk to the fetus.

Fetal alcohol syndrome (FAS) is the most serious form of fetal alcohol spectrum disorder (FASD). It occurs due to alcohol exposure in the womb.

FAS can cause serious developmental issues, affecting both a person’s body and mind. These issues are what doctors base their diagnoses on. Ultrasounds during pregnancy do not provide a reliable means of diagnosing FAS.

FAS is preventable by avoiding drinking alcohol during pregnancy. Treatment for FAS may involve a mixture of medication and specialized therapies, but there is no known cure for the condition.