|Year : 2017 | Volume
| Issue : 2 | Page : 85-86
Clinical questions: Responses to clinical queries from readers: Down's syndrome
Associate Professor, Department of Obstetrics and Gynecology, Christian Medical College, Vellore, Tamil Nadu, India
|Date of Web Publication||18-May-2017|
Associate Professor, Department of Obstetrics and Gynecology, Christian Medical College, Vellore, Tamil Nadu
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Benjamin S. Clinical questions: Responses to clinical queries from readers: Down's syndrome. Curr Med Issues 2017;15:85-6
As a primary care doctor, how can I assess the possibility of “Down's Syndrome” in a developing fetus in a primigravida above 35 years of age. I want to know the basic tests.
Down's syndrome is the most common autosomal trisomy with a prevalence of approximately 1 in 800 live births. Along with other disorders such as Klinefelter's syndrome (a sex chromosome aneuploidy) and Turner's syndrome, it forms a group of chromosomal disorders called aneuploidies. By definition, aneuploidy is a condition where there is an extra or missing chromosome leading to an unbalanced chromosome number in the nucleus of the cell. Aneuploidy may result in a nonviable pregnancy or offspring with congenital birth defects, failure to thrive, mild to severe intellectual disability, and a shortened lifespan. Screening tests are available for aneuploidy in all trimesters of pregnancy. The purpose of screening is to inform the parents about the possibility of chromosomal abnormalities and the options available so that they can make an informed choice.
The recommended test worldwide for screening for fetal aneuploidy at present is the “ first trimester combined test.” This test includes ultrasound and biochemical tests.,,,
- Nuchal translucency [Box 1]
- Presence or absence of nasal bone.
- Free B-human chorionic gonadotropin
- Pregnancy-associated plasma protein A.
This test should ideally be offered to all pregnant women, irrespective of the maternal age. Newer tests such as noninvasive prenatal testing represent a potential option for the future.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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