3-O-methyl Estradiol is a synthetic estrogen known for its ability to interfere with microtubule networks in V79 Chinese hamster cells, with an EC50 value of 9 µM. At a concentration of 20 µM, it inhibits the proliferation of these cells by 92%. Additionally, when male rats on a high-cholesterol diet are administered 3-O-methyl Estradiol (25 mg in a 0.2 ml solution, p.o.), it results in decreased serum cholesterol levels and increases body weight loss, suggesting feminizing effects. It has also been utilized as a standard for quantifying 17β-estradiol in hen urine.