Screens for: Blood type for Rh incompatibility, certain diseases like Hepatitis, HIV status and blood counts that may indicate issues like anemia, gestational diabetes, infection, etc. It can also be done as a pregnancy test by looking for hCG in the blood.
Who does it: This is usually performed by a lab tech, nurse or other health care worker.
How it is done: It is done with a needle to puncture your vein to draw blood for the screening.
When is it done: It can be done at any point in pregnancy. It is typically done at the beginning of pregnancy and repeated as needed at various points in pregnancy such as a part of the Alpha-fetoprotein screening, gestational diabetes testing, etc.
Accuracy: Depends on the blood sample, and method of testing for which particular test.
Risk to mom: There is a slight pain during the testing. You may bleed a bit and have a bruise from the location where the blood is drawn. A very small percentage of women will have further trouble with the site like infection.
Risk to pregnancy/baby: None known.
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