Ovulation test paper suddenly white plate does not mean that the bed, ovulation test paper needs continuous monitoring, in order to determine the time of ovulation, you need to start monitoring from the 8th to 10th day of menstruation, the test paper will go from negative to weak positive, after that there is a positive, there is a strong positive to weak, means that ovulation is about to occur, generally will be in 36 hours or so ovulation. If it is in the continuous monitoring of ovulation, the strong positive suddenly turned negative, it means that ovulation is about to occur, not the bed, if you are preparing for pregnancy, you can arrange for sex every other day, there will be a chance of conception. About 10 days after ovulation sex, you can determine whether you are pregnant by taking a blood test for HCG, and two weeks later you can determine whether you are pregnant by urinating early pregnancy test paper. During the preparation for pregnancy, we should pay attention to the regularity of life, avoid staying up late, avoid exposure to harmful substances, women in the preparation for pregnancy, need to take folic acid, in order to prevent fetal neural tube malformation.