How do i know if i am a carrier of trisomy 18?

Chromosome study: Most trisomy 18's arise as a new error on meiosis during the formation of a womans egg.It is not "carried" like a sickle trait. There is a rare possibility that infants with trisomy 18 picked up the material from a parent with a balanced switch between 2 chromosomes.The babies study would show the translocation not t18, parents would need to be studied in such a case.

Trisomy 18: Partial Trisomy 18 can be inherited from someone who has no signs of Trisomy 18. These people do not have an extra chromosome 18 – instead genetic material can be rearranged between Chromosome 18 & another chromosome. However Trisomy 18 is usually the result of random events while egg or sperm form. It is usually not inherited. Agree w Dr. Ferguson - re studies on infant. It is very rare.