oestriol
Last edited 05/2020
Estriol is a weak endogenous estrogen formed by irreversible transformation of estradiol and estrone
- oestriol (estriol E3)
- oestrogen the placenta secretes during pregnancy
- alos is the peripheral metabolite of oestradiol and o estrone
- is not secreted by the ovary
- has a lower estrogenic potency than estradiol does (ranging from 1/10 to 1/100, 1/80 most often cited)
- and a greater relative affinity for alpha than for beta estrogenic receptors (È3:1)
- estriol is a very well-known molecule with a long-lasting clinical experience
- estriol has been demonstrated to be safe in terms of endometrial proliferation (2)
Reference:
- Hamilton KJ et al. Estrogen Hormone Biology.Curr Top Dev Biol. 2017; 125: 109–146.
- Cano A et al. The therapeutic effect of a new ultra low concentration estriol gel formulation (0.005% estriol vaginal gel) on symptoms and signs of postmenopausal vaginal atrophy: results from a pivotal phase III study.Menopause 2012 Oct;19(10):1130-9