Start of Pregnancy Week 3 : Day 1 with 265 days to go

Strangely enough the first few weeks of your pregnancy are in fact the most active. Not really in terms of growth but in development. In fact in the first 24 hours of your pregnancy, the fertilized cells have gone from 2 cells to sixteen, but this doesn't increase in physical size. The cells are also being manufactured with the help of nutrients from the ovum that you produced.

As the cells moves from the fallopian tubes to the uterus and important change takes place. Fluid passes into the center of the cell ball, which divides the cells into two groups. Cells on the outside will develop to form the placenta, and the cells on the inside will form your baby.

At this stage of your pregnancy, your body still doesn't even realize that the baby exists.

Once the cell ball comes to rest in the uterus the implantation process begins. The cell ball will attach itself to the wall of your uterus, so that it can receive protection, nutrition and the oxygen that it will require in order to fully develop. During the implantation process the cell ball actually burrows into the uterus wall, which may result in some light spotting. Once implantation takes place the cell ball is actually called an embryo.

By day 21 of your pregnancy, the cell ball will already be 0.004 of an inch in length

Interesting Pregnancy Fact : 10 Cell balls could fit into the space of this period .