 Dear students, in this topic we shall discuss the hormones produced by placenta. During pregnancy, placenta produces large quantities of hormones, which are essential for the maintenance of pregnancy. These hormones include four types of hormones. The human-choreonic-gonadotropin, astrogenspergestron and human-choreonic-someto-memotropin. We shall discuss all these in detail. The human-choreonic-gonadotropin hormone is secreted shortly after the embryo implants with the uterus. Its secretion then rises rapidly and reaches a maximum till 10 to 12 weeks of pregnancy. After this, its secretion decreases during the 16th to 20th week and then remains constant at a steady level during the remainder period of pregnancy. This hormone causes the persistence and growth of corpus luteum. It causes corpus luteum to secrete its hormones, astrogens and progestron until the placenta fully takes over the production of these hormones. This hormone also prevents the process of menstruation. It also causes the endometrium of uterus to grow and store large amounts of nutrients. Dear students, this hormone, human-choreonic-gonadotropin, also affects the testes of male-dwelling fetus. It exerts a stimulatory effect on the interstitial cells of the developing testes and causes the production of testosterone by them. This testosterone, which is produced during the gastric period, causes the fetus to grow into a male, producing primary male sexual characters. If testosterone is not produced at this stage, female primary sexual characters are produced. This hormone also causes the testes to descend into the scroterm before birth. Dear students, now we shall discuss the role of astrogens secreted by placenta during pregnancy. During pregnancy, placenta produces enormous amounts of astrogens. If we look at the normal production of astrogens in a female, in the end period of pregnancy, more than 30 astrogens are produced by this placenta. During pregnancy, placenta produces astrogens. These astrogens exert mainly proliferative functions on the reproductive and associated organs of the female. These effects include enlargement of the uterus, enlargement of breasts, and growth of breast ductal structure. These also include enlargement of external genitalia. Astrogens also play a role in the relaxation of pelvic ligaments so that to make the pubic symphysis elastic for the passage of the fetus through birth canal during parturation or childbirth. Dear students, the progestron is also secreted in tremendous amounts by placenta. Progestron's secretion during pregnancy has more than 10 times the normal level. This hormone decreases the contractility of the uterus to prevent any chance of spontaneous abortion. It also causes the development of deciduous cells in the endometrium. These cells play an important role in providing nutrition during embryo's early development when placenta was not developed. Dear students, now we shall discuss the fourth placental hormone that is human-choreonic-someto-memo-tropin. This hormone starts to be secreted during the fifth week of pregnancy. This hormone is primarily involved in the metabolic processes and development of breasts and lactation. This hormone also promotes protein tissues just like the functions of growth hormone. It also causes decreased sensitivity of tissues to insulin and also decreases the utilization of glucose by the tissues of mother. It also promotes free fatty acids from the fat stores, providing alternative sources of energy. This hormone acts more as a general metabolic hormone which has specific nutritional implications for both the mother and the fetus.