Follicle 10*8mm belongs to the dominant follicle, usually 5~7 days follicle will be mature and discharge, specific how long ovulation has individual differences. General follicle development to 18 * 20mm belongs to the development of mature follicles will soon be discharged, follicle 10 * 8mm belongs to the dominant follicle, the dominant follicle every day after the follicle growth of 1 ~ 2 millimeters, generally 5 ~ 7 days follicle will be developed and discharged. However, as the body’s hormone levels are affected by emotions, the environment and other effects of the growth rate is different, you can vaginal ultrasound to monitor follicular development, to determine the time of follicular development and maturation and discharge. If you want to prepare for pregnancy, it is recommended that the follicles develop to 10*8mm to become dominant follicles after intermittent vaginal ultrasound to monitor follicle development, to determine the follicle development maturity, close to the discharge in time to have intercourse with a greater chance of pregnancy.