This is often the result of otitis media with effusion which occurs in 50–70% and chronic ear infections which occur in 40 to 60%. Ear infections often begin in the first year of life and are partly due to poor eustachian tube function. Excessive ear wax can also cause hearing loss due to obstruction of the outer ear canal. Even a mild degree of hearing loss can have negative consequences for speech, language understanding, and academics. It is important to rule out hearing loss as a factor in social and cognitive deterioration. Age-related hearing loss of the sensorineural type occurs at a much earlier age and affects 10–70% of people with Down syndrome. Heart
The rate of congenital heart disease in newborns with Down syndrome is around 40%. Of those with heart disease, about 80% have an atrioventricular septal defect or ventricular septal defect with the former being more common. Mitral valve problems become common as people age, even in those without heart problems at birth. Other problems that may occur include tetralogy of Fallot and patent ductus arteriosus. People with Down syndrome have a lower risk of hardening of the arteries. Cancer
Although the overall risk of cancer in Down syndrome is not changed, the risk of testicular cancer and certain blood cancers, including acute lymphoblastic leukemia (ALL) and acute megakaryoblastic leukemia (AMKL) is increased while the risk of other non-blood cancers is decreased.
The risk from the procedure is greater the earlier it is performed, thus amniocentesis is not recommended before 15 weeks gestational age and chorionic villus sampling before 10 weeks gestational age. Abortion rates
About 92% of pregnancies in Europe with a diagnosis of Down syndrome are terminated. As a result, there is almost no one with Down syndrome in Iceland and Denmark, where screening is commonplace. In the United States, the termination rate after diagnosis is around 75%, but varies from 61% to 93% depending on the population surveyed. Rates are lower among women who are younger and have decreased over time. When asked if they would have a termination if their fetus tested positive, 23–33% said yes, when high-risk pregnant women were asked, 46–86% said yes, and when women who screened positive are asked, 89–97% say yes. After birth
The diagnosis can often be suspected based on the childs physical appearance at birth. An analysis of the childs chromosomes is needed to confirm the diagnosis, and to determine if a translocation is present, as this may help determine the chances of the childs parents having further children with Down syndrome. Parents generally wish to know the possible diagnosis once it is suspected and do not wish pity. Screening
Guidelines recommend screening for Down syndrome to be offered to all pregnant women, regardless of age. A number of tests are used, with varying levels of accuracy. They are typically used in combination to increase the detection rate.