Ovulation test paper may be weakly positive when menstruation is approaching, suggesting that there is a low concentration of luteinizing hormone in the urine. If the ovulation test paper is weakly positive before the period, it is usually of little reference significance and only suggests that it is not during the period of ovulation. Usually, there is no accidental ovulation around the period. If the ovulation test paper is positive or strong positive, it only indicates that ovulation will occur in about 24 hours – 48 hours. If there is only one weak positive test, you can wait for 1 hour and retest to see if there is any change in the result. Ovulation test strips can be used to assist in checking ovulation, but there is a certain degree of error in their results. If you want to know the exact situation of ovulation, it is recommended to consult a doctor for an ultrasound examination. Ultrasound can clarify the shape of the ovaries and the state of the follicles within them, and combined with the changes in hormone levels in the body, it can more accurately predict the time of ovulation. Therefore, the ovulation test paper can show a weak positive when you are about to have your period, suggesting that you are not in the ovulation period, and if you have sex at this time, the risk of pregnancy is low. The accuracy of ovulation test paper in monitoring ovulation is limited. If you want to know the ovarian status and the time of ovulation accurately, you can go to the gynecology clinic for an ultrasound examination.