Key Points continued

has both growth-hormone-like and prolactin-like activities.

• The placenta constitutively synthesizes large amounts of progesterone from cholesterol taken up from the maternal circulation.

• Although the placenta cannot synthesize 19-carbon steroids, it produces large amounts of estrogens by aromatizing androgens secreted by the maternal and fetal adrenal glands.

• Corticotropin-releasing hormone (CRH) produced by the placenta stimulates the fetal pituitary to secrete ACTH and also acts directly on the fetal adrenal cortex to stimulate production of dehydroepiandrosterone-sulfate which serves as a precursor for placental estrogen production.

• Estrogens drive their own production and the production of progesterone by increasing placental uptake of cholesterol and conversion to pregnenolone, which serves as a precursor for placental production of progesterone and fetal adrenal production of dehydroepiandro-sterone-sulfate.

• Parturition is initiated by convergence of self-amplifying effects of CRH, cortisol, prostaglandins, mechanical stretching of the myometrium, and perhaps other factors that are not fully understood.

• Oxytocin promotes uterine contractions and speeds up parturition but is not secreted until parturition has been initiated.

• Estrogen and progesterone promote growth and branching of the mammary duct system.

• Prolactin and hCS in the presence of estrogen and progesterone during pregnancy stimulate growth of the mammary alveolar tissue.

• Tactile stimulation of the nipples or sensory input related to nursing signal release of oxytocin.

• Oxytocin stimulates myoepithelial cells surrounding the mammary alveoli and ducts to contract and deliver pressurized milk to the lactiferous ducts.

• Suckling stimulates prolactin secretion.

• Prolactin is secreted in response to suckling and stimulates milk synthesis in preparation for the next episode of suckling.

Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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