It takes about 6~7 days from conception to implantation. After ovulation, the egg cell will survive in the body for 12~24 hours, and when you have sex at this time, the sperm will pass through the uterus to reach the fallopian tube and combine with the egg cell to form a fertilized egg, and then the fertilized egg will reach the uterine cavity along with the peristalsis of the cilia of the fallopian tube, and the process of implantation can be completed in about 6~7 days from the time of fertilization. If a woman has unprotected sex and finds that her period is delayed, it is recommended that she go to the hospital in time to have her blood HCG level checked, as well as to have an ultrasound and a progesterone test to determine whether pregnancy is occurring and whether her pregnancy is in a normal state.