According to the National Down Syndrome Society, one in every 691 babies (approximately 6,000) in the United States is born with Down syndrome each year with approximately 400,000 Americans affected and living with the condition in the United States. It is important to spread awareness about the most common genetic condition.
Down syndrome occurs when an individual has a full or partial extra copy of chromosome 21. This additional genetic material alters the course of normal development and causes the physical characteristics and health problems associated with the condition. Down syndrome occurs in people of all races and economic levels and although researchers know how Down syndrome is caused, no one knows why.
Types of Down syndrome:
Trisomy 21 (nondisjunction) is the most common affecting about 95% of individuals,
Translocation Down syndrome affects about 3% of individuals and
Mosaic Down syndrome affects about 2% of individuals. All three types are genetic conditions but only about 1% of all cases have a hereditary component (passed from parent to child through the genes).
One factor that increases the risk for having a baby with Down syndrome is the mother's age. Women who are 35 years or older who become pregnant are more likely to have a pregnancy affected by Down syndrome than women who become pregnant at a younger age. However, 80% of babies with Down syndrome are born to mothers less than 35 years because there are more births among younger women.
Common symptoms include:
- A flattened face, especially the bridge of the nose
- Almond-shaped eyes that slant up
- Shorter in height as children and adults
- Small stature (short neck, small ears, small hands and feet)
- Small pinky fingers that sometimes curve toward the thumb
- A tongue that tends to stick out of the mouth
- Tiny white spots on the iris (colored part) of the eye
- A single line across the palm of the hand – each individual is unique and may possess these characteristics to different degrees or not at all
- Poor muscle tone or loose joints
Doctors can diagnose Down syndrome during pregnancy or after the baby is born. Prior diagnosis during pregnancy can allow parents and families to prepare for their baby's special needs.
Screening tests can tell whether the pregnancy has a lower or higher chance of having Down syndrome and can help decide whether a diagnostic test might be needed. Screening tests do not provide an absolute diagnosis.
- Blood tests and an ultrasound are taken which allows the technician to look for extra fluid behind the baby's neck which could indicate a genetic problem.
- In 2010, a new test (PAPP-A or Pregnancy associated Plasma protein-A) became available and is recommended for women who are more likely to have a pregnancy affected by Down syndrome and is typically completed during the first trimester (first 3 months of pregnancy).
Diagnostic tests can typically detect whether or not a baby will have Down syndrome and are generally performed after a positive screening test and the following can be tested:
- Chorionic villus sampling (CVS) – examines material from the placenta
- Amniocentesis – examines the amniotic fluid (fluid from the sac surrounding the baby)
- Percutaneous umbilical blood sampling (PUBS) – examines blood from the umbilical cord
Health Problems Associated Among Children with Down syndrome:
Because almost half of babies born with Down syndrome have a heart defect, all newborns should receive an echocardiogram (an ultrasound picture of the heart) and consult with their physician.
One or more major birth defects or other medical problems include:
- Hearing loss (around 75%)
- Obstructive sleep apnea – a condition where the person's breathing temporarily stops while asleep (affects 50 -75%)
- Ear infections (affects 50 -70%)
- Eye diseases (up to 60%), such as cataracts and eye issues requiring glasses
- Heart defects present at birth (around 50%)
Less common health problems include:
- Intestinal blockage at birth requiring surgery
- Hip dislocation
- Thyroid disease
- Anemia (red blood cells can't carry enough oxygen to the body) and iron deficiency (anemia where the red blood cells don't have enough iron)
- Leukemia in infancy or early childhood
- Hirschsprung disease (affects the large intestines and bowel movements)
Services and Living with Down syndrome:
Down syndrome is a lifelong condition and quality services are offered to improve and develop physical and intellectual abilities to the highest potential with programs focusing on speech, occupational and physical therapy. Many children may need extra help or attention in school growing up but are still able to attend regular classes with proper guidance.
Many individuals with Down syndrome can live independently, have jobs and lead productive lives well into adulthood. Seeing a physician regularly, connecting with friends and family and staying involved with the community is important for continued development. Life expectancy has increased dramatically in recent decades from 25 years in 1983 to 60 years presently. While individuals with Down syndrome do experience different cognitive delays, each is an individual and can contribute to society with their own individual traits they possess.