Acts on uterus, kidneys,
brain, smooth muscle, breasts, bones, and cellular membranes.
Metabolized to other
active hormones.
What are some of the
functions and roles of progesterone in the body?
Counteracts estrogen's
tendency to induce excess growth in the endometrial lining of the
uterus.
Builds new bone tissue,
leading to increased bone mass and density.
Necessary for maintenance
of pregnancy.
Decreases uterine
contractions.
Prepares and
maintains uterine lining for implantation of fertilized egg
Prepares breasts for
lactation.
Assists in raising HDL-cholesterol
levels (if combined with
estrogen therapy) and
ultimately reduces risk of heart disease.
Synthetic
progesterone (progestin) has an overall negative effect on HDL-cholesterol
levels because it vasocontricts.
What is the
difference between "progestin" and "progesterone?"
The main difference is
in the derivative. Progestin’s are synthetic (i.e. man-made) molecules
developed to act like natural progesterone. Natural progesterone is a
molecule that is plant derived and is biologically equivalent to the hormone
produced in our bodies. Progestin’s do not have as broad a spectrum of
activity as natural progesterone, and have a wide range of side
effects. Whereas progesterone may cause some mild to moderate
drowsiness, progestin’s can cause: