Pregnancy tests

Definition

Pregnancy tests are diagnostic tools that detect the presence of human chorionic gonadotropin (hCG) in urine or blood to determine pregnancy. They often utilize enzyme-linked immunosorbent assays (ELISAs) for high sensitivity and specificity.

5 Must Know Facts For Your Next Test

1. Pregnancy tests commonly use monoclonal antibodies against hCG for detection.
2. Enzyme immunoassays (EIAs) used in pregnancy tests can quantitatively measure hCG levels.
3. The sensitivity of pregnancy tests is crucial for early detection, often detecting hCG at levels as low as 25 mIU/mL.
4. False positives in pregnancy tests can occur due to certain medical conditions like trophoblastic disease or exogenous hCG administration.
5. The specificity of ELISA-based pregnancy tests minimizes cross-reactivity with similar glycoprotein hormones like luteinizing hormone (LH).

Review Questions

• What hormone is detected by pregnancy tests to confirm pregnancy?
• How do ELISAs contribute to the accuracy of pregnancy tests?
• What factors could lead to a false positive result in a pregnancy test?

Related terms

hCG: Human chorionic gonadotropin, the hormone detected by pregnancy tests.

Monoclonal Antibody: An antibody produced by a single clone of cells, specific to one antigenic site.

Cross-Reactivity: When an assay reacts with unintended substances, affecting its specificity.