Question

What are the hormones secreted by the Placenta?

Answer 1

Hint During pregnancy, the placenta is an organ that develops in the uterus. This structure gives your growing infant oxygen and nourishment while also removing waste from his or her blood. The placenta adheres to the uterine wall, and the umbilical cord of your baby emerges from it.

Complete answer:
The placenta is a key endocrine organ in addition to delivering molecules between the mother and the foetus. It turns out that the placenta produces a large variety of hormones and cytokines that have significant effects on ovarian, uterine, mammary, and foetal physiology, as well as the mother's other endocrine systems.
Hormones of Steroids
The most well-known placental hormones are sex steroids. All mammals produce two major groups of organisms:
Progestins are molecules that attach to the progesterone receptor and release progesterone. Because of its importance in sustaining the endometrium and thus the conceptus' survival, progesterone is often referred to as the "pregnancy hormone."
Estrogens are produced by the placenta in a variety of forms. Estriol is the most common oestrogen generated by the placenta in women, however the equine placenta produces a distinct set of estrogens not found in other mammals. Placental estrogens can be made from foetal androgens, placental progestins, or other steroid precursors, depending on the species.
Hormones of Protein
The placentas of many species manufacture a variety of protein and peptide hormones. They affect the mother's endocrine system, foetal metabolism, and the mother's readiness to support her offspring postpartum.
Chorionic gonadotropins: These hormones, like pituitary gonadotropins, have the action of activating the gonads. Primates and equids are the only species known to manufacture placental gonadotropin.
Hormones of Protein
The placentas of many species manufacture a variety of protein and peptide hormones. They affect the mother's endocrine system, foetal metabolism, and the mother's readiness to support her offspring postpartum.
Relaxin is a hormone that is considered to work in tandem with progesterone to keep a woman pregnant. It also causes the pelvic ligaments to relax near the end of pregnancy, which may help with parturition. Relaxin is produced by the placenta in certain species, but the corpus luteum is the primary source in others.

Note: Monotremata and Marsupialia are the other two existing subdivisions of the Mammalia class of animals; Placentalia is one of them. The placentals differ from other mammals in that the foetus is carried to a relatively late stage of development in the mother's uterus.