Follicle 21*14mm, usually can ovulate in 24-48 hours. Generally the diameter of mature follicle is 18~23mm, 21mmx14mm follicle is close to mature follicle, and it may ovulate within 24-48 hours, each woman’s physique and body hormone situation is different, the specific time of ovulation varies from person to person. Some patients may not ovulate, and at this time, they need to take ovulation injections to promote ovulation. After the follicle is discharged, it can survive in the body for 1-2 days, and male sperm can survive in the body for 2-3 days. At this stage, you can appropriately increase the number of coitus, at this time, after coitus, the sperm and the egg to meet the chances of increased, the success rate of female pregnancy will also increase. Ovulation women should keep a relaxed mood, pay attention to diet, more rest, ensure sufficient sleep, avoid excessive anxiety.