Total estrogens comprise the total quantity of estrone, estradiol,and estriol. The estrogens are involved in the development offemale sex organs and secondary sex characteristics. Beforethe ovum is fertilized, the main action of the estrogens is onthe growth and function of the reproductive tract to prepare itfor the fertilized ovum. During the follicular phase of the menstrual cycle, the totalestrogens level shows a slight increase. The production oftotal estrogens then increases markedly to peak at aroundday 13. The peak is of short duration and by day 16 of the cyclelevels will be low. A second peak occurs at around day 21 ofthe cycle. If fertilization does not occur, the production of totalestrogens decreases. In post-menopausal women, the concentration of all estrogensdecreases substantially and estrone becomes the predominantestrogen. In pregnant women, the concentration of all estrogensescalates and estriol becomes the predominant estrogen.A total estrogens test is commonly indicated to:
- Aid in diagnosis of sex steroid metabolism related conditions, for example, premature or delayed puberty, and aromatase and 17 alpha-hydroxylase deficiencies.
- Follow-up female hormone replacement therapy in post-menopausal women.
- Prognose antiestrogen therapy, for example, aromataseinhibitor therapy.