Triple test for diagnosis of down’s syndrome includes all of the following except –
**Core Concept**
The triple test, also known as the triple screen or multiple marker test, is a prenatal screening test used to assess the risk of Down's syndrome (Trisomy 21) and other chromosomal abnormalities. The test measures levels of three substances in a pregnant woman's blood: alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3).
**Why the Correct Answer is Right**
The triple test is a combination of three markers that are used to estimate the risk of Down's syndrome. Alpha-fetoprotein (AFP) is a protein produced by the fetus, while human chorionic gonadotropin (hCG) is a hormone produced by the placenta. Unconjugated estriol (uE3) is an estrogen produced by the placenta. The levels of these markers are measured in the maternal serum and compared to a reference range to determine the risk of Down's syndrome.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided, but typically, the triple test includes AFP, hCG, and uE3.
* **Option B:** This option is not provided, but typically, the triple test includes AFP, hCG, and uE3.
* **Option C:** This option is not provided, but typically, the triple test includes AFP, hCG, and uE3.
* **Option D:** This option is not provided, but typically, the triple test does not include amniotic fluid analysis, which is a separate diagnostic test.
**Clinical Pearl / High-Yield Fact**
It's essential to note that the triple test is a screening test, not a diagnostic test. A positive result indicates an increased risk of Down's syndrome, but it does not confirm the diagnosis. Further diagnostic tests, such as amniocentesis or chorionic villus sampling (CVS), are needed to confirm the diagnosis.
**Correct Answer:**
(Replace the placeholder with the actual correct answer)