LH Surge Positive Morning, Negative Evening? Understanding Ovulation Tests

No, you did not do it wrong. It is possible to get a positive ovulation test in the morning and a negative one in the evening. This is because the LH surge that triggers ovulation typically lasts for only 24-36 hours and then declines quickly. As a result, an ovulation test may be positive one day and negative the next, even if ovulation has occurred. If you are trying to conceive, it is important to have intercourse on the day of your LH surge or the day after it to increase your chances of getting pregnant.