After teaching a pregnant woman about the hormones produced by the placenta, the nurse determines that the teaching was successful when the woman identifies which hormone produced as being the basis for pregnancy tests?

A. Human placental lactogen (hPL) is a hormone produced by the placenta that helps regulate the metabolism of the mother and fetus, but it is not used as the basis for pregnancy tests. It plays a role in modulating the metabolic state of the mother during pregnancy to facilitate the energy supply of the fetus.

B. Estrogen (estriol) is another hormone produced by the placenta, which is important for maintaining pregnancy and preparing the body for childbirth. However, it is not the hormone detected by pregnancy tests. Estriol levels increase significantly during pregnancy but are not used as a marker for pregnancy tests.

C. Progesterone (progestin) is crucial for maintaining the uterine lining and supporting early pregnancy. While it is essential for a successful pregnancy, it is not the hormone that pregnancy tests detect. Progesterone helps prevent uterine contractions and supports the endometrium.

D. Human chorionic gonadotropin (hCG) is the hormone detected by pregnancy tests. It is produced by the placenta shortly after the embryo attaches to the uterine lining. The presence of hCG in the blood or urine is a reliable indicator of pregnancy, which is why it is the basis for pregnancy tests.