---

Pregnancy test

A wide variety of tests have been developed for the determination of pregnancy. These methods generally involve the testing of blood or urine for levels of pregnancy antigens or other compounds which are indicative of pregnancy. Tests for the detection of pregnancy are generally based on the determination of hormones which are produced by the developing placenta, such as gonadotropic hormones similar to those produced by the anterior pituitary gland and steroid hormones similar to those of the ovary and adrenal gland. Immunologic tests have been used for the diagnosis of pregnancy, which estimate the human chorionic gonadotropin (hCG) in the urine or body fluid (serum, plasma, etc.) of a pregnant woman. This hormone is found in body fluids (blood serum and urine) only during pregnancy, with the exception of several other very rare hormone-producing conditions of the body. Home pregnancy tests for hCG in urine include a variety of enzyme immunoassays, hemagglutination inhibition, and antibody-antigen agglutination tests which are effective to indicate pregnancy from 0 to 7 days after a missed period. Confirmation by physician is recommended, particularly to determine abnormal gestation such as ectopic pregnancy.

---