Fetal alcohol syndrome

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Fetal alcohol syndrome



Fetal alcohol syndrome


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Fetal alcohol syndrome

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A 1-day-old male infant is brought to the newborn nursery two hours after birth. He was born via vaginal delivery at 38 weeks gestation. The infant’s mother did not receive prenatal care. Family history is unremarkable for hereditary disorders. Weight and length are at the 5th percentile. Vitals are within normal limits. Physical examination reveals microcephaly, short palpebral fissures, a thin vermillion border, and a smooth philtrum. A harsh holosystolic murmur is heard at the lower left sternal border on cardiac auscultation. This infant’s physical exam findings are most likely secondary to in-utero exposure to which of the following?  

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Atrial septal defect (ASD) p. 305

fetal alcohol syndrome p. 306

Developmental delay

fetal alcohol syndrome p. 639


in fetal alcohol syndrome p. 640

Fetal alcohol syndrome p. 306, 638, 639

holoprosencephaly in p. 505

Holoprosencephaly p. 505

fetal alcohol syndrome p. 639

Intellectual disability

fetal alcohol syndrome p. 639


fetal alcohol syndrome p. 639

Patent ductus arteriosus (PDA)

fetal alcohol syndrome p. 306

Tetralogy of Fallot p. 304

fetal alcohol syndrome p. 306

Ventricular septal defect (VSD) p. 305, 728

fetal alcohol syndrome p. 306


Fetal alcohol syndrome, or FAS, occurs because of maternal use of alcohol during pregnancy.

It’s currently the leading cause of intellectual disability in the US and can cause characteristic physical abnormalities.

Normally, the fetus is connected to the placenta by the umbilical cord, so the fetus gets oxygen and nutrients from the mother.

Unfortunately, ethanol and toxic alcohol metabolites like acetaldehyde also pass freely through the placenta, but the fetal liver doesn’t have the necessary enzymes to metabolize them, so they build up inside the fetus really fast.

In FAS, ethanol interferes with cell division and proliferation, cell growth and differentiation, and with the migration of mature cells to their final location in the developing embryo, which affects the development of various fetal tissues, including the brain.

Alcohol-induced brain damage includes partial or complete agenesis of the corpus callosum, which links the two hemispheres together, so it either forms incompletely, or not at all.

This causes intellectual disability and seizures.

When the frontal cortex and the hippocampus are affected, this causes poor memory and communication skills, as well as intellectual disability.

The cerebellum can also be smaller in size, called hypoplasia, leading to trouble with movement and balance.

The most common symptom of FAS is growth retardation, resulting in low height and weight.


Fetal alcohol spectrum disorder (FASD) is an umbrella term describing the range of effects that can occur in a person whose mother drank alcohol during pregnancy. FASD can include physical, behavioral, and intellectual disabilities.

There is no safe level of alcohol consumption during pregnancy, and drinking any amount can cause FASD. FASD is 100% preventable if women don't drink alcohol during pregnancy. If a woman does drink alcohol during pregnancy, there is no way to know for sure how her child will be affected.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison’s principles of internal medicine" McGraw Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "Diagnostic and Statistical Manual of Mental Disorders (DSM-5 )" American Psychiatric Association (2013)

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