Estro™ is an herbal tincture containing plant-derived phytoestrogens, including black and blue cohosh, that are used extensively in Europe. Phytoestrogens have been researched for their ability to support a woman’s body. Estro™ is an herbal tincture containing plant-derived phytoestrogens, including black and blue cohosh, that are used extensively in Europe. Phytoestrogens have been researched for their ability to support a woman’s body. Estro™ is an herbal tincture containing plant-derived phytoestrogens, including black and blue cohosh, that are used extensively in Europe. Phytoestrogens have been researched for their ability to support a woman’s body. 