Frequently Asked Questions (FAQ)
1. What exactly is Trisomy 18?
Trisomy 18, also called Edwards syndrome, is a genetic condition caused by an extra copy (three copies total) of chromosome 18, leading to developmental and medical complications.
2. How frequently does Trisomy 18 occur?
Trisomy 18 occurs in approximately 1 in 5,000 live births.
3. What causes the extra chromosome in Trisomy 18?
It happens randomly when chromosomes fail to separate properly during cell division in the egg or sperm, usually by chance.
4. Does parental age affect the risk of Trisomy 18?
Yes, the risk is higher in older mothers, particularly those aged over 35.
5. Can Trisomy 18 be inherited from parents?
Typically no; most cases of Trisomy 18 occur randomly and are not inherited.
6. What are the common physical features of a baby with Trisomy 18?
- Low birth weight
- Small head size (microcephaly)
- Clenched fists with overlapping fingers
- Rocker-bottom feet
- Small jaw and mouth
- Prominent back of the head (occiput)
7. Are there types or variations of Trisomy 18?
Yes, three variations exist:
- Full trisomy 18 (extra chromosome in every cell)
- Mosaic trisomy 18 (extra chromosome in some cells)
- Partial trisomy 18 (only part of chromosome 18 duplicated)
8. Which type of Trisomy 18 is most severe?
Full trisomy 18 is typically the most severe, while mosaic and partial forms can be milder, with varied symptoms.
9. How is Trisomy 18 diagnosed prenatally?
Through prenatal screening tests (ultrasound, maternal blood tests, Non-Invasive Prenatal Testing [NIPT]), and confirmed by diagnostic tests like amniocentesis or chorionic villus sampling (CVS).
10. Can ultrasound detect Trisomy 18?
Ultrasound may indicate markers, such as specific heart defects, growth restrictions, or physical features, but definitive diagnosis requires genetic testing.
11. Can Trisomy 18 be cured?
There is no cure, but many symptoms can be managed with supportive medical care.
12. What’s the life expectancy for children born with Trisomy 18?
Many infants (around 50-60%) with Trisomy 18 survive less than one week. About 10% survive their first birthday, though many live longer with proper medical care.
13. Are heart defects common with Trisomy 18?
Yes, over 90% of babies with Trisomy 18 have congenital heart defects, which can severely affect survival and quality of life.
14. Do all babies with Trisomy 18 have severe intellectual disabilities?
Yes, virtually all children with Trisomy 18 have significant developmental delays and intellectual disabilities.
15. Can babies with Trisomy 18 leave the hospital after birth?
Some babies can go home with careful medical management and supportive care, while others require ongoing hospitalization due to medical complexity.
16. Is it common to have feeding issues with Trisomy 18?
Yes, feeding difficulties are common, often requiring assistance such as feeding tubes or specialized nutrition support.
17. What type of medical specialists typically care for a child with Trisomy 18?
Care typically involves pediatricians, cardiologists, geneticists, neurologists, therapists, nutritionists, and specialized nursing support.
18. Is recurrence risk high for having another child with Trisomy 18?
No, recurrence risk is usually low (~1%), as most cases are random. However, genetic counseling is recommended for personalized risk assessment.
19. Can Trisomy 18 be prevented?
No, it occurs randomly and cannot be prevented. Early prenatal screening and genetic counseling can help families plan or make informed decisions.
20. Where can families find support and resources?
Helpful resources include:
- Genetic counseling services and parent support groups.
