Question

Which of the following is a non-invasive technique to detect fetal disorders during early pregnancy?
A. Chorionic villi sampling
B. Amniocentesis
C. Foetoscopy
D. None of the above

Answer 1

The non-invasive technique refers to those techniques that do not involve any surgical procedure. There is no involvement of the surgical instrument to remove tissues or cells. Fetal disorders are abnormalities in the genetic constitution or development of the growing fetus. Detecting fetal disorders in the early stages is important to prevent later complications.

Complete answer: Sexual reproduction is a complex process that involves the fusion of gametes from two different parents. The fusion of male and female gametes results in the formation of zygote. The formation of zygote results in conception or pregnancy.
-The genetic makeup of the zygote derives from two haploid gametes. These gametes fuse to form a diploid nucleus. During the cell multiplication after fertilization, recombination takes place causing variations in the zygote. These variations can be lethal sometimes.
-So, any damage to the genetic constitution needs to be detected earlier. If not detected, these variations lead to the damaged development of the zygote. The chorionic villi sampling technique involves a medical procedure where a sampling test is done in early pregnancy to detect congenital abnormalities.
-It involves the removal of villi tissue from the villi of the chorion. So, this is not a non-invasive technique. Amniocentesis is also a technique that involves surgical removal of amniotic fluid from the amniotic sac. A hollow needle is used to insert inside the uterus.
-This is used to analyze the health condition of the fetus. This test checks for chromosomal or genetic abnormalities but it is not a non-invasive test. Foetoscopy is a technique involving surgical access to the fetus, amniotic activity, umbilical cord, and fetal side of the placenta.
-It is an endoscopic procedure. A small incision is made in the abdomen to reach the abdominal wall, uterus, and amniotic cavity. This technique allows for biopsy of abnormal blood vessels.
Therefore, the right answer is option D.

Note: The medical procedures allow for accurate testing of any abnormalities present in the zygote. Amniocentesis was earlier also being used in testing the gender of the zygote. This is unethical in India now as people used it to abort female fetuses due to gender disparities. This leads to a decreased sex ratio in India.