The ideal time to collect a urine sample is in the afternoon, although tests will provide accurate results from 10 am to early evening. Luteinizing hormones (LH) are produced in your body in the morning and have the highest concentration of LH in the afternoon.

It's important to collect urine samples at the same time each day to ensure consistency. To obtain a concentrated urine sample, it's recommended to reduce liquid intake about 2 hours before collecting urine, as a diluted sample may prevent the test from detecting an LH peak. Additionally, some doctors recommend testing every 12 hours to avoid missing the LH peak, which can be very short for some women.