Implantation occurs between five and eight days after conception, according to Merck Manual. This process marks the first major step in the pregnancy following fertilization of the egg. Once the sperm and egg meet, they form a zygote. This zygote, now called a blastocyst, will travel to the uterus where it will implant into the lining, causing implantation. Symptoms of implantation often vary for every woman and every pregnancy.
Asymptomatic
It is possible to experience no symptoms during implantation. A woman may not realize her pregnancy for another week or so when her period is late.
Cramping
Implantation can cause cramping that is similar to menstrual cramping, according to the Mayo Clinic. The cramping may last for one or two days before disappearing. Some women misattribute the cramps to an upcoming period. It is possible to have no cramps but to have some spotting.
Bleeding
Bleeding can happen once the fertilized egg attaches to the uterine lining. The attachment causes a small amount of tissues or blood to detach from the lining. Some of the blood that passes through the vagina may be brown in color due to being shed during implantation and taking some time to exit the body. Bleeding during implantation is spottier and lighter in color than what is experienced during a period. The timing is also a bit off, as the woman's period would actually occur seven or more days from this point. Typical bleeding will only last a day or two.
