ad. 23. What is the advantage of chorionic villus sampling over amniocentesis?
The main advantages of this examination are time and safety! Chorionic villus sampling can be performed a lot earlier, thus gaining several precious weeks (on average, the result is ready a month before the result from amniocentesis). The optimal time to undergo the examination is completed 11 weeks (11+0) which overlaps with a screening test of the first trimester (nuchal translucency + biochemical exam).
In respect of the fact that an inserted needle does not enter an amniotic cavity, i.e. the baby’s “home”, the examination is seen as safe all over the world. The latest research indicates a high safety of chorionic villus sampling. The study was based on the population of about 10,000 women. It was observed that among patients who underwent chorionic villus sampling there were less cases of miscarriage (excluding termination of pregnancy for medical reasons)!
Nowadays, the assessment of an AFP level in the amniotic fluid, which is carried out during the amniocentesis does not contribute anything to the result. At present, defects such as split spine or gastroschisis can be detected during an ultrasound scan even in 100% of cases.