Antenatal and postnatal screening Flashcards
What does antenatal screening do
identifies the risk of a disorder so that further tests and a prenatal diagnosis can be offered
What are dating scans
given at 8-14 weeks which determines pregnancy stage and due date, are used with tests for marker chemicals which vary normally during pregnancy
What are anomaly scans
18-20 weeks may detect serious physical abnormalities in the fetus
Why are blood and urine tests carried out throughout pregnancy
to monitor the concentrations of marker chemicals
What can measuring a chemical at the wrong time lead to
False positive
What can an atypical chemical concentration lead to
diagnostic testing to determine if the fetus has a medical condition
What does CVS involve
obtaining CVS cells from the placenta
When would CVS be carried out
11-13 weeks
Why would a women be offered an CVS
if she has a higher risk result from a screening for downsyndrom
What are the risks of CVS
there is a 1 to 2 pecent risk of miscarriage
What is amniocentesis
amniocenteses cells are obtained from amniotic fluid
When is amniocentesis carried out
15-18 weeks
Why would a women be offered an amniocentesis
if she has a higher risk result from a screening for downs syndrom
What are the cells from CVS and amniocentesis used for
cells are cultures to produce a karyotype to diagnose a range of conditions
What is the risk of amniocentesis
1 percent risk of mmiscarriage
