Clearblue Ovulation Test with Dual Hormone Indicator is the only one that typically identifies your 4 best days to get pregnant naturally, that’s 2 more than any other test. By accurately tracking 2 key fertility hormones, estrogen & luteinising hormone (LH), it identifies 2 Peak fertility days, like all other ovulation tests, but also typically 2 High fertility days before that, so you have more opportunities to get pregnant. Its unique, smart algorithm is the only one that can adapt every time you test to indicate your personal wider fertility window. Have intercourse on High & Peak fertility days to maximise your chances of getting pregnant naturally, the unmistakably clear Clearblue Digital smiley face will tell you when your body is ready. Clearblue Ovulation Test with Dual Hormone Indicator is over 99% accurate at detecting the LH surge.