The reasons why women are still strongly positive with ovulation test paper after ovulation are as follows. First, it may be due to the presence of hormonal imbalance in the female body, which appears to have high levels of luteinizing hormone. As a result, high levels of the hormone are still present after ovulation at the time of testing. Second, it may also be due to errors in reagents or inaccurate testing methods during the test, resulting in strong positives, which can be detected by doing ultrasound. If you are able to have your period within the prescribed time, you can observe for the time being. If there is any abnormality, then blood test for sex hormone level is more definite, in order to give symptomatic treatment as soon as possible.