What substance does the fetus secrete?

The fetus secretes several substances, with one of the most notable being fetal urine, which is primarily composed of water and waste products. Additionally, the fetus produces hormones such as human chorionic gonadotropin (hCG), which helps maintain pregnancy, and other substances involved in growth and development. Amniotic fluid, which surrounds the fetus, is also partially derived from fetal secretions.