Infertile couples struggle with the question of which moment they will ovulate and when they have a good chance of getting pregnant with intercourse. In fact, ovulation is an explosive, momentary event. It is difficult for us to capture that moment even through examination. But we know that sperm and eggs have a life span. The time that sperm can survive and maintain fertilization in the female reproductive tract is 3 to 5 days. The egg has a shorter lifespan, with the ability to fertilize only 12 to 24 hours after ovulation. Therefore, if you have intercourse from 3 to 5 days before ovulation to one day after ovulation, you have a chance of getting pregnant. Ma|, Infertility Treatment Center, Qilu Hospital, Shandong University