Which hormone is detected in pregnancy tests?

The hormone detected in pregnancy tests is Human Chorionic Gonadotropin (hCG). This hormone is produced by the placenta shortly after the embryo attaches to the uterine lining. Its presence in urine or blood is a key indicator of pregnancy.

Pregnancy tests are specifically designed to identify hCG levels, as it is typically not found in significant amounts in women who are not pregnant. The detection of hCG typically occurs around the time a missed period happens, marking it as an effective early marker for pregnancy.

Other hormones like estrogen and progesterone play significant roles during pregnancy and the menstrual cycle but are not specifically used for pregnancy testing since their levels can vary widely even in women who are not pregnant. Luteinizing hormone, while important for the regulation of the menstrual cycle and ovulation, does not serve as a marker for pregnancy and is not utilized in pregnancy tests.