Trisomy 18, also known as Edwards Syndrome, is a genetic disorder caused by the presence of an extra chromosome 18 in a baby's cells. It is a serious condition that affects many parts of the body and is usually fatal. Babies born with Trisomy 18 often have severe physical and mental disabilities, including heart defects, low birth weight, and developmental delays.

Common symptoms of Trisomy 18 include:

- Low birth weight
- Small head size
- Abnormal facial features
- Heart defects
- Abnormal fingers and toes
- Kidney and urinary tract defects
- Gastrointestinal problems
- Seizures
- Developmental delays
- Weak muscle tone (hypotonia)
- Poor growth

Trisomy 18 is caused by an extra chromosome 18 in each cell of the body. This extra chromosome can be inherited from a parent or can occur as a random event during the formation of reproductive cells (eggs and sperm).

Treatment for Trisomy 18 is supportive and depends on the severity of the condition. Treatment may include physical therapy, occupational therapy, speech therapy, nutritional support, and medications to help with breathing and other medical issues. Surgery may be necessary to correct certain physical abnormalities. In some cases, palliative care may be recommended to help manage symptoms and improve quality of life.

The risk factors for Trisomy 18 include:

1. Advanced maternal age: Women over the age of 35 are more likely to have a baby with Trisomy 18.

2. Family history: If a family member has had a baby with Trisomy 18, the risk increases.

3. Previous pregnancy with Trisomy 18: If a woman has had a previous pregnancy with Trisomy 18, the risk increases.

4. Abnormal ultrasound: If an ultrasound shows abnormalities, the risk increases.

5. Abnormal blood test: If a blood test shows abnormal levels of certain hormones, the risk increases.

There is no cure for Trisomy 18, but there are medications that can help manage symptoms. These medications can include anticonvulsants to control seizures, diuretics to reduce fluid buildup, and medications to help with breathing. Additionally, physical and occupational therapy can help improve the quality of life for those with Trisomy 18.