We don't have synonyms for estriols yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are striola, estrous and estriol.
(n) :
(American spelling, biochemistry, steroids, pharmacology) A relatively weak natural estrogenic hormone that is a glycol C₁₈H₂₄O₃ found in the body chiefly as a metabolite of estradiol, is the main estrogen secreted by the placenta during pregnancy, and is the estrogen typically found in the urine of pregnant women.
(n) :
(American spelling, biochemistry, steroids, pharmacology) A relatively weak natural estrogenic hormone that is a glycol C₁₈H₂₄O₃ found in the body chiefly as a metabolite of estradiol, is the main estrogen secreted by the placenta during pregnancy, and is the estrogen typically found in the urine of pregnant women.