Pentagestrone acetate (PGA), sold under the brand names Gestovis and Gestovister, is a progestin which was described in the literature in 1960 and was introduced by Vister in

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

in 1961. It is the 3-

cyclopentyl Cyclopentane (also called C pentane) is a highly flammable alicyclic hydrocarbon with chemical formula C5H10 and CAS number 287-92-3, consisting of a ring of five carbon atoms each bonded with two hydrogen atoms above and below the plane. It occu ...

enol ether In organic chemistry an enol ether is an alkene with an alkoxy substituent. The general structure is R2C=CR-OR where R = H, alkyl or aryl. A common subfamily of enol ethers are vinyl ethers, with the formula ROCH=CH2. Important enol ethers includ ...

17α-hydroxyprogesterone acetate Hydroxyprogesterone acetate (OHPA), sold under the brand name Prodox, is an orally active progestin related to hydroxyprogesterone caproate (OHPC) which has been used in clinical and veterinary medicine. It has reportedly also been used in bi ...

. PGA, along with

quingestrone Quingestrone, also known as progesterone 3-cyclopentyl enol ether (PCPE) and sold under the brand name Enol-Luteovis, is a progestin medication which was previously used in birth control pills in Italy but is now no longer marketed. It is taken ...

(the 3-cyclopentyl enol ether of progesterone), is said to have very similar properties to those of

dydrogesterone Dydrogesterone, sold under the brand name Duphaston & Dydroboon among others, is a progestin medication which is used for a variety of indications, including threatened or recurrent miscarriage during pregnancy, dysfunctional bleeding, infertil ...

, a pure progestogen and close analogue of progesterone. PGA is orally active, was provided in 10 and 20 mg capsules, and has been used to treat

habitual abortion Recurrent miscarriage is three or more consecutive pregnancy losses. In contrast, infertility is the inability to conceive. In many cases the cause of RPL is unknown. After three or more losses, a thorough evaluation is recommended by American So ...

and

menstrual disorder A menstrual disorder is characterized as any abnormal condition with regards to a person's menstrual cycle. There are many different types of menstrual disorders that vary with signs and symptoms, including pain during menstruation, heavy bleeding ...

s at a dosage of 10 to 20 mg/day. It has been said to have equivalent

potency Potency may refer to: * Potency (pharmacology), a measure of the activity of a drug in a biological system * Virility * Cell potency, a measure of the differentiation potential of stem cells * In homeopathic dilutions, potency is a measure of how ...

intramuscular Intramuscular injection, often abbreviated IM, is the injection of a substance into a muscle. In medicine, it is one of several methods for parenteral administration of medications. Intramuscular injection may be preferred because muscles have ...

progesterone. The combination of 20 mg/day PGA and 100 μg/day mestranol is an effective

ovulation Ovulation is the release of eggs from the ovaries. In women, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells. After ovulation, during the luteal phase, the egg will be available to be fertilized ...

inhibitor in women. The effective dosage of PGA in the

menstrual delay test Menstruation (also known as a period, among other colloquial terms) is the regular discharge of blood and mucosal tissue from the inner lining of the uterus through the vagina. The menstrual cycle is characterized by the rise and fall of ho ...

has been studied.

Chemistry

PGA, also known as 17α-acetoxyprogesterone 3-cyclopentyl enol ether, is a synthetic

pregnane Pregnane, also known as 17β-ethylandrostane or as 10β,13β-dimethyl-17β-ethylgonane, is a C21 steroid and, indirectly, a parent of progesterone. It is a parent hydrocarbon for two series of steroids stemming from 5α-pregnane (originally allop ...

steroid and a

derivative In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. F ...

progesterone Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the m ...

and 17α-hydroxyprogesterone.

References

Abandoned drugs Acetate esters Cyclopentyl ethers Ethers Pregnanes Progestogen esters Progestogen ethers Progestogens {{Steroid-stub

Chemistry

See also

References