Medical use
Progesterone is used as a medication. It is used in combination with estrogens mainly in hormone therapy for menopausal symptoms and low sex hormone levels in women. It is also used in women to support pregnancy and fertility and to treat gynecological disorders. Progesterone has been shown to  prevent miscarriage in women with 1) vaginal bleeding early in their current pregnancy and 2) a previous history of miscarriage. Progesterone can be taken by mouth, through the vagina, and by injection into muscle or fat, among other routes. Chemistry
Progesterone is a naturally occurring pregnane steroid and is also known as pregn-4-ene-3,20-dione. It has a double bond (4-ene) between the C4 and C5 positions and two ketone groups (3,20-dione), one at the C3 position and the other at the C20 position. Synthesis
Progesterone is commercially produced by semisynthesis. Two main routes are used: one from yam diosgenin first pioneered by Marker in 1940, and one based on soy phytosterols scaled up in the 1970s. Additional (not necessarily economical) semisyntheses of progesterone have also been reported starting from a variety of steroids. For the example, cortisone can be simultaneously deoxygenated at the C-17 and C-21 position by treatment with iodotrimethylsilane in chloroform to produce 11-keto-progesterone (ketogestin), which in turn can be reduced at position-11 to yield progesterone. Marker semisynthesis
An economical semisynthesis of progesterone from the plant steroid diosgenin isolated from yams was developed by Russell Marker in 1940 for the Parke-Davis pharmaceutical company. This synthesis is known as the Marker degradation.
Diencephalic syndrome, or Russells syndrome, is a rare neurological disorder seen in infants and children and characterised by failure to thrive and severe emaciation despite normal or slightly decreased caloric intake. Classically there is also locomotor hyperactivity and euphoria. Less commonly diencephalic syndrome may involve skin pallor without anaemia, hypoglycaemia, and hypotension. The syndrome is a rare but potentially fatal cause of failure to thrive in children. Failure to thrive presents on average at seven months of age. Of note the syndrome is not associated with developmental delay. There may be associated hydrocephalus.Diencephalic syndrome was first described by Dr. A. Russell in 1951. It is usually caused by a brain tumor such as a low-grade glioma or astrocytoma located in the hypothalamic-optic chiasmatic region. It is not yet understood how diencephalic syndrome causes the effects on appetite and metabolism which are seen, though inappropriately high growth hormone release has been proposed, as has excessive β-lipotropin secretion and overall increased metabolic demand. It is treated with nutritional optimisation while the underlying lesion is treated with chemotherapy, surgery or radiotherapy. == References ==