This is an exciting week if you are pregnant. At this time, towards the end of the week you should be able to see a positive result on a pregnancy test. In the NOD list you can see that the first positive test will be visible approximately 2 days before your next period, around 27 days. This is still early to do a pregnancy test as your body is only now beginning to get flooded with the hCG (pregnancy hormone). Waiting another week will provide you with a much clearer indication of pregnancy.
The fused sperm and egg cell is known as a `zygote` which is the same as `fertilised egg`. This zygote contains the genetic characteristics of both parents. For 24 hours after fertilization there isn't much activity but then the zygote begins to split and will reach around one hundred new cells after approximately four days. At this time the divided egg is called a `blastocyst` because it resembles a small blackberry.
This blastocyst is moved along the uterus but the ciliae. Although it moves only a few centimeters, it takes around five to seven days to make this journey. Once the egg embeds itself on the wall of the uterus it has reached 0.1 to 0.2mm in size. Small cells will attach themselves to the outside layer of the blastocyte and these will eventually become the placenta. The egg will now disappear completely into the uterine wall which is now thick and well vascularized by the progesterone now flooding the body. Cell division will continue now until the baby eventually consists of over a billion cells. From the time when the blastocyte becomes embedded in the uterine wall it is known as an embryo.
In this week your body will be busy making a variety of hormones. These hormones help to protect the embryo by ensuring your body doesn't see it as a foreign intruder and try to eject it. The progesterone makes the cervix impermeable and the mucus plug will form, closing the cervix off to protect the fetus.
The uterus is now being supplied with extra blood there is a possibility that a little spot of bleeding will occur if a blood cell is ruptured.
This is called implantation bleeding. It is not serious and affects on average one in three women. Providing there is no pain, abdominal cramping and the blood loss is not too severe then you should not worry, however if any of these symptoms do occur you should inform your doctor.