Progesterone nervous tissue, especially in the brain, and in adipose (fat) tissue, as well. During human pregnancy, progesterone is produced in increasingly high amounts by the ovaries and placenta. At first, the source is the corpus luteum that has been "rescued" by the presence of human chorionic gonadotropin (hCG) from the conceptus. However, after the 8th week, production of progesterone shifts to the placenta. The placenta utilizes maternal cholesterol as the initial substrate, and most of the produced progesterone enters the maternal circulation, but some is picked up by the fetal circulation and used as substrate for fetal corticosteroids. At term
Menstrual cycle use of birth control pills should affect eating behaviour as they minimise or remove the fluctuations in hormone levels. The neurotransmitter serotonin is also thought to play a role in food intake. Serotonin is responsible for inhibiting eating and controlling meal size, among other things, and is modulated in part by ovarian hormones. A number of factors affect whether dieting will affect these menstrual processes: age, weight loss and the diet itself. First, younger women are likely to experience menstrual irregularities due to their diet. Second, menstrual abnormalities are more likely with more weight loss. For example, anovulatory cycles can