Symmetrical intrauterine growth restriction is a type of intrauterine growth restriction (IUGR) where all fetal biometric parameters tend to be less than expected (below the 10th percentile) for the given gestational age. Both length and weight parameters are reduced.
Please, refer to the article on asymmetrical intrauterine growth restriction for the discussion of asymmetrical IUGR.
On this page:
Pathology
As a general rule, fetuses with this type of IUGR pattern may present at an earlier stage in gestation compared with the asymmetrical IUGR pattern.
Etiology
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aneuploidic syndromes
infections, e.g. TORCH 7
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other
topical use of maternal fluorinated glucocorticoid (rare) 3
external agents, e.g. nicotine, alcohol, heroin, ionizing radiation 7
Radiographic features
Ultrasound
All sonographic biometric parameters tend to be symmetrically reduced. Therefore, fetuses have normal or near-normal:
HC (head circumference) : AC (abdominal circumference) ratio
FL (femoral length) : AC (abdominal circumference) ratio
Differential diagnosis
Differential considerations on ultrasound assessment include:
incorrect dates
lower end of normal variation, i.e. if parents are small