Ovulation test strips, which detect luteinizing hormone in the urine, will reach a peak about 24-48 hours before ovulation, and when the peak occurs after intercourse, it will improve the chances of pregnancy. Luteinizing hormone will also decline, so there will be a weak positive, which is normal. It is recommended to use urine around 10 o’clock in the morning to do ovulation test paper monitoring, can not use morning urine to do the test, because around 10 o’clock, the value of luteinizing hormone in the urine, is relatively high. In addition, ovulation monitoring starts on the twelfth day of menstruation and continues until the eighteenth day of menstruation, when monitoring can be stopped.