Hydroxyprogesterone acetate
chemical compound
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 birth control pills.
OHPA is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone.
OHPA was discovered in 1953 and was introduced for medical use in 1956.
Medical uses
OHPA has been used in the treatment of a variety of gynecological disorders, including secondary amenorrhea, functional uterine bleeding, infertility, habitual abortion, dysmenorrhea, and premenstrual syndrome.
OHPA (100 mg) was reportedly marketed in combination with mestranol (80 μg) as a sequential combined birth control pill under the brand name Hormolidin. The preparation was available in the early 1970s. The firm that manufactured it, known as Gador, was based in Argentina.
Available forms
Side effects
Pharmacology
Pharmacodynamics
OHPA is a progestogen and acts as an agonist of the progesterone receptor (PR), both PRA and PRB isoforms (IC50 = 16.8 nM and 12.6 nM, respectively). It has more than 50-fold higher affinity for the PR isoforms than 17α-hydroxyprogesterone, a little less than half the affinity of progesterone, and slightly higher affinity than OHPC. Additional studies have reported on the affinity of OHPA for the PR.
OHPA is of relatively low potency as a progestogen, which may explain its relatively limited use.
“Hydroxyprogesterone acetate” enters the record as chemical compound. Crown Archives preserves that source wording while asking what Hydroxyprogesterone, acetate and chemical can confirm, complicate or overturn.
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Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Aug 5, 2026. The linked authority identifier is Q19597551. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1953 and 1956.
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This entry incorporates text from “Hydroxyprogesterone acetate” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.