Ovulation Test has a history of 50 years. The primary method used rabbit or frog but the sensitivity is very low. Contemporary LH tests include direct coagulation way,coagulation inhibition way,RIA and ELISA. As the application of the monoclonal antibody technology these years, "sandwich enzyme-immunology way" is getting more and more popular. The method employs a unique combination of two specific monoclonal antibodies with two different sites on one LH molecule to determine the quantity of LH in the patient`s urine according to the intensity of the color, in the help of color effect of enzyme boosting reaction.The sensitivity can reach 5mIU/ml. In 30 to 60 minutes, the test could be finished, without using any special instrument or isotope, while increasing the specificity in the same time.