Many fetuses with trisomy 18 do not survive to birth. Affected infants who do survive have a number of congenital abnormalities, which can include an
- abnormally small head,
- absence of one or both testes,
- neurodevelopmental delays,
- failure to thrive,
- low birth weight,
- short stature,
- underdeveloped jaw,
- drooping of upper eyelid or wide-spaced eyes,
- abnormal deviation of fingers, and
- clenched hands.
Abnormalities of multiple organs may be present. The average life span for infants born with trisomy 18 is 3 days to 2 weeks.
Cause of trisomy 18
The presence of an extra copy of chromosome 18 causes the genetic condition.
Other trisomy 18 symptoms and signs
- Abnormal Deviation of Fingers
- Abnormally Small Head
- Absence of One or Both Testes
- Clenched Hands
- Drooping of Upper Eyelid or Wide-Spaced Eyes
- Failure to Thrive
- Low Birth Weight
- Neurodevelopmental Delays
- Short Stature
- Underdeveloped Jaw
Main Article on Trisomy 18 Symptoms and Signs
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