Final answer:
The procedure for obtaining fetal blood through ultrasound-guided puncture is known as Percutaneous umbilical blood sampling (PUBS) or cordocentesis. It is used for diagnosing fetal conditions and differs from chorionic villus sampling and amniocentesis. Genetic counselors assist couples in understanding and managing the outcomes of genetic tests.
Step-by-step explanation:
The procedure for obtaining fetal blood through US guided puncture to detect fetal problems such as fetal blood disorders or fetal infection is referred to as d) Percutaneous umbilical blood sampling (PUBS). This technique is also known as cordocentesis and involves taking a blood sample directly from the fetal umbilical cord. It is different from chorionic villus sampling and amniocentesis, which involve sampling of placental tissue and amniotic fluid respectively. PUBS is primarily utilized to diagnose fetal abnormalities, infections, and blood conditions, and it is typically performed when other testing, such as ultrasound, indicates a potential problem or when the results from amniocentesis or CVS are inconclusive.
The term prenatal genetic diagnosis (PGD) refers to a set of procedures done for screening human embryos during in vitro fertilization before implantation. Although PGD is somewhat related to the aim of prenatal diagnosis, it involves a separate set of procedures focused on the diagnosis, selection, and implantation of embryos free from genetic abnormalities.
In discussions of fetal health and prenatal testing, it's important to also be aware of how the placenta and the fetal and maternal blood supplies interact. While there is no blood cell exchange between mother and fetus, the fetal and maternal blood systems are in close proximity within the chorionic villi, facilitating the exchange of substances, and potential exposure to fetotoxic substances such as alcohol, which can lead to fetal alcohol spectrum disorders (FASD).
With advances in genetic testing, determining carrier status for genetic diseases like Fragile X or cystic fibrosis is now possible with a simple blood draw. Genetic counselors play a crucial role in this process, providing education and support to couples who need to make informed decisions about genetic testing and coping with the results.