trisomy 18
noun [ U ] medical specialized (also Trisomy 18) uk/ˌtrɪ.sə.mi eɪˈtiːn/ us/ˌtraɪ.soʊ.mi eɪˈtiːn/
（因多出一条18号染色体而引起的）18三体
a rare and very serious genetic condition in which there is an additional copy of chromosome 18 in some or all of the body's cells
Other chromosomal abnormalities include trisomy 18 (Edwards' syndrome) and trisomy 13 (Patau syndrome). 其他染色体异常包括18三体（爱德华氏综合征）和13三体（帕塔综合征）。
Some children with Trisomy 18 have reached adulthood. 有些患有18三体的儿童能长大成人。
Synonym: Edwards' syndrome
- More examples
- Mean survival time (MST) for trisomy 18 is 14.5 days, and MST for trisomy 13 is 7 days.
- One recent case involved a fetus diagnosed with Trisomy 18, a deadly chromosomal abnormality.
- Amniocentesis is a test that detects most chromosomal disorders such as Down's syndrome, trisomy 18 and spina bifida by inserting a needle through the abdomen to remove fluid from the uterus.