Invasive fetal testing is a procedure that is done to directly access the fetus or the placenta to obtain samples of analysis like genetic testing or assessing fetal well being.
The most common methods of invasive fetal testing are taking of amniotic fluid also called amniocentesis and chorionic villus sampling or CVS, taking placental tissue.
The tests are more accurate but carry a slight risk of miscarriage or harm to the fetus.
Amniocentesis is when a needle is inserted through the abdominal wall and into the uterus to collect a sample of amniotic fluid.
Chorionic Villus Sampling or CVS is when a small sample of the placenta or chorionic villus is taken, often through the abdomen or cervix.
Another method of invasive fetal testing is through umbilical cord blood sampling which is when a needle is inserted into the umbilical cord to obtain a blood sample for analysis although it's less common.
Reasons for invasive fetal testing include genetic testing, fetal well being assessment and high risk pregnancies.
Women that are at a higher risk of having a child with genetic disorders may be offered the invasive fetal testing.
And in some cases invasive fetal testing such as cordocentesis or umbilical cord blood sampling is used to assess fetal oxygen levels or diagnoses of fetal infections.
Amniocentesis and CVS are mainly used to identify chromosomal abnormalities such as Down syndrome or genetic conditions.
There are some risks of invasive fetal testing which include possible miscarriage, fetal injury and infection.