A positive urine pregnancy test indicates the presence of which hormone?

A positive urine pregnancy test indicates the presence of human chorionic gonadotropin (hCG), which is a hormone produced by the placenta shortly after a fertilized egg attaches to the uterine lining. This hormone plays a crucial role in maintaining pregnancy, particularly in its early stages.

When a pregnancy occurs, the levels of hCG rise rapidly and are detectable in the urine, which is why many home pregnancy tests are designed to detect this hormone. The test typically involves a chemical reaction that occurs when hCG is present in the urine, leading to a visual indicator, such as a color change or a line on the test strip.

The other hormones listed do not indicate the presence of a pregnancy. Luteinizing hormone (LH) is involved in the regulation of the menstrual cycle and ovulation but does not confirm pregnancy. Estrogen is primarily responsible for the development of female secondary sexual characteristics and the regulation of the menstrual cycle. Progesterone supports the early stages of pregnancy but is not used as a marker in urine tests for confirming pregnancy. Its levels can fluctuate throughout the menstrual cycle and in response to pregnancy but are not the hormone detected by standard pregnancy tests. Thus, hCG is specifically the hormone associated with confirming a pregnancy through urine