Implantation occurs 9 days after ovulation. However, this does not necessarily mean that the process will take exactly 9 days after. Sometimes, implantation ranges between 6 to 12 days after ovulation, as well. For the purpose of this question, implantation happens during the beginning of the pregnancy stage wherein the embryo, which is called blastocyst during this stage, sticks to the uterine wall. When a woman’s fertilized egg attaches itself to the uterine wall, that is only when implantation happens.
The signs of implantation sometimes do not have a noticeable symptom until pregnancy has been confirmed. However, some women develop some symptoms during implantation such as cramps, spotting or bleeding, temperature rise of the basal body, or a temperature dip which can last for one day.