The standard follicle on the 13th day of menstruation is usually around 17-25mm. Usually when the largest follicle disappears, which means that ovulation occurs in the body, it can be monitored through regular medical means. The general choice of ovulation test paper will be able to understand your ovulation status, so that you can also make effective treatment in a timely manner according to your body condition, and couples preparing for pregnancy can also greatly improve their chances of pregnancy by having intercourse during ovulation. During the ovulation phase, you should not only keep your mood relaxed, but also not be overly nervous and anxious, try to ensure a balanced nutrition, eat more fresh fruits and vegetables, and replenish the vitamins and proteins needed in your body, which are good for your health and can promote a more stable fertilization of the egg.