Ovulation Test Midstream gives women a greater chance of detecting their fertile days, even if their cycle lengths are variable. ME3512 LH Urine Ovulation Test Midstream measure the level of Luteinizing Hormone (LH) in the urine with results of over 99% accuracy. LH Test detects levels of LH as low as 20 mIU/mL within just 3 to 5 minutes. LH Rapid Test Midstream can be used by simply dipping the test tip into the urine sample for several seconds, then wait to read the results. Each midstream is sealed in individual foil pouch.