Genetics Counselling Task

4 Pages • Essays / Projects • Year Uploaded: 2022

Year 11 GENETICS COUNSELLING TASK GRADE A - CVS is a method of obtaining a picture of the chromosomes, of the embryo or fetus to detect genetic defects. Jan Mohr, a researcher first attempted and described the CVS procedure in 1968 but the original trans-cervical technique was rejected as it was found to be unsafe. Later on, further research was done by the researchers of University College Hospital in London on CVS and in 1984 they successfully developed a relatively safe trans-abdominal to carry out CVS. The current CVS test collects a small sample of the chorionic villi which is found in the placental tissue close to the mother’s bloodstream. There are two ways to collect the sample. One way is to insert a tube through the vagina and cervix, or a second way is to insert a thin tube, also known as a catheter through the abdomen and into the uterus (Brind’Amour, 2009). In both the methods the doctor performing the test uses an ultrasound monitor to see the position of the placenta and baby. The reason for using ultrasound machine is to prevent puncturing the amniotic sac. The tissue samples taken in the test contain cells with the same DNA and genetic information as the embryo, allowing for accurate predictions of the health of the developing baby. The entire procedure often takes less than twenty minutes and recovery time is usually minimal. The patient stays awake during the procedure. CVS is a generally safe testing procedure, however, its risks in approximately 1 to 2 percent of women include puncturing of the amniotic sacs, cramping, bleeding, infection, and rhesus sensitization occurring when a Rh-negative mother develops antibodies to the fetus’s blood due to Rh protein entering her bloodstream (Brind’Amour, 2009). In very rare circumstances CVS can cause physical abnormalities in the developing baby.

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