Progesterone exogenous

Historically, the 1950s represented an important time in the control of human fertility. It was during that decade that the first combined oral contraceptives were developed. Shortly after the discovery that the exogenous administration of hormones such as progesterone successfully blocked ovulation, the use of hormonal steroids quickly became the most popular method of contraception worldwide. Specifically, combined oral contraceptives represent the most commonly used reversible form of contraception today and it is estimated that nearly 100 million women worldwide take oral contraceptives.1 Further, in the United States, it is estimated that at some time during their lives, more than 80% of women born since 1945 have used oral... 

Exogenous progesterone and benzodiazepines may have important pharmacodynamic interactions in that cognitive impairment to benzodiazepines may be enhanced with exogenous progesterone (Kroboth et al. 1985 McAuley et al. 1995). 

Two female sex hormones, estradiol-17 and progesterone, and one male sex hormone, testosterone, are used as growth promoters on beef cattle (Fig. 7.1). By nature, they are all endogenous products playing an important role in controlling reproductive functions in humans and animals. When applied exogenously they will enter the same metabolic pathways as the endogenously produced molecules. 

Progesterone is used primarily as a growth promotant in cattle in combination with estradiol or its esters. Administration is carried out by subcutaneous implant in the ear, which is subsequently discarded at slaughter. When administered exogenously, progesterone enters the same metabolic pathways and is indistinguishable from the endogenously produced compound. 

Scinto J, Enrione M, Bernstein D, Bernstein IL. In vitro leukocyte histamine release to progesterone and pregna-nediol in a patient with recurrent anaphylaxis associated with exogenous administration of progesterone. J Allergy Clin Immunol 1990 85 228. 

Use of Hormones to Alter Normal Endocrine Function. Because of the intrinsic control mechanisms in the endocrine system, administration of exogenous hormones can often affect the normal release of hormones. This fact can be exploited in certain situations to cause a desired change in normal endocrine function. For instance, oral contraceptives containing estrogen and progesterone inhibit ovulation by inhibiting the release of LH and FSH from the anterior pituitary. 

Bachman, K.C. 1982. Effect of exogenous estradiol and progesterone upon lipase activity and spontaneous lipolysis in bovine milk. J. Dairy Sci. 65, 907-914. 

Allen W E 1983 The effect of human chorionic gonadotropin and exogenous progesterone on luteal function during early pregnancy in pony mares. Animal Reproduction Science 6 223-228... 

Many studies have evaluated the relationship between exogenous hormones and development of breast cancer. Postmenopausal estrogen replacement therapy has been the subject of several recent meta-analyses, with conflicting results. The recently reported NCI-sponsored Women s Health Initiative study randomized 80,000 women to take postmenopausal estrogen replacement therapy combined with progesterone or a placebo. This study reported an... 

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