The ClinicalGuard LH Urine Ovulation Test is an accurate and easy-to-use test to pinpoint a useru0026#39;s ovulation days.nTest strips have sensitivity of 25 mIU, or 25 ng/LnNegative: Only one color band appears in the Control Zone, with no band in the Test Zone.nPositive: Distinct color bands appear in both the Control and Test Zones.nThis product only available on Amazon from ClinicalGuardnThe ClinicalGuard LH Urine Ovulation Test is an accurate and fast-acting ovulation test. It works by detecting the presence of Luteinizing Hormone ("LH") in urine. LH increases dramatically just before ovulation - a woman' most fertile time of the month to conceive. The increase in LH, also known as LH-Surge, is the hormonal change that precipitates ovulation (the release of the egg). The ClinicalGuard test takes just a few seconds to collect your urine, and five minutes to obtain results. Note: The color intensity of the test bands on the test may vary depending on the concentration of LH hormone detected.