Which hormone reflects placental function and remains increased throughout pregnancy, aiding estrogen and progesterone production?

• A. Human placental lactogen
• B. Human chorionic gonadotropin
• C. Estradiol
• D. Progesterone

Answer: (A)

Hormones produced by the placenta reflect how well it’s functioning, and the one that stays elevated throughout pregnancy is human placental lactogen. This hormone is made exclusively by placental trophoblasts, and its level rises progressively as the placenta grows. Because its secretion tracks placental mass and activity, it serves as a useful indicator of placental function over the entire gestation. It also helps regulate maternal metabolism to support fetal growth, creating a hormonal milieu that supports the placenta’s role in producing estrogen and progesterone. By contrast, hCG is mainly high in early pregnancy and declines, while estradiol and progesterone are essential steroid hormones produced by the placenta but do not provide the same continuous marker of placental function across all stages of pregnancy.