Pharmatest offers an uterotrophic bioassay designed for testing potentially estrogenic or anti-estrogenic compounds (either drug candidates or endocrine disruptors) in vivo according to the OECD guidelines. Uterus is a natural target for estrogens and the tissue growth response is rapid. Uterus responds to estrogens in two ways, initially increasing the weight due to water imbibition followed by a weight gain due to tissue growth.

The uterus weights (both wet and blotted) of pre-pubertal rats are evaluated following administration of the test compound. Potent reference estrogen and antiestrogen compounds are administered to control animals.