Patient's question:
Patient's description: My sister is 41 years old and 16 weeks pregnant. Today, I went to pick up her blood test results and saw that the report stated: The screening results are positive, indicating a higher risk of the pregnant woman carrying a child with Down syndrome, placing her in the high-risk group. It is recommended to consult the relevant clinic for further evaluation and confirmation. I asked the doctor, "What does a child with Down syndrome mean? Can it be prevented?" Thank you.Doctor's answer:
Generally, the main characteristics of children with Down syndrome include intellectual disability, delayed physical development, and a distinctive facial appearance. The children have wide-set eyes, a low and flat nasal bridge, small palpebral fissures, upward slanting outer corners of the eyes, epicanthal folds, small ears, a narrow and small hard palate, and the tongue often protrudes outside the mouth, with excessive drooling. They are short-statured, have a smaller head circumference than normal, and bone age often lags behind chronological age. Teething is delayed and often misaligned. Their hair is fine, soft, and sparse. Their limbs are short, and due to ligamentous laxity, their joints can be excessively flexible. Their fingers are thick and short, with the little finger often bent inward.If a baby is diagnosed with Down syndrome, the decision to terminate the pregnancy can be made according to the parents' wishes. This condition is caused by the most common chromosomal variation. The risk of the baby having Down syndrome increases with the mother's age. Between the ages of 20 and 24, the incidence rate is 1/1490, at age 40 it is 1/106, and at age 49 it is 1/11. The reason is that as the mother's age increases, the likelihood of chromosomal nondisjunction during oogenesis also increases. However, on the other hand, approximately 80% of children with the syndrome are born to mothers under the age of 35. This is related to the higher proportion of pregnancies in women under 35. Additionally, there are cases where the extra chromosome comes from the father, with the ratio of paternal to maternal origin being 1:4. Families with a high potential risk of the disease are often recommended for genetic counseling and genetic tests such as "amniocentesis."