The first cell division takes place today.
A two-cell ball is formed from the single cell created by your ovum and your partner’s sperm. This cell-ball floats freely in the uterine tube, pushed along by gravity and the movement of the cilia that line that tube.
Early Pregnancy Factor (EPF), an immuno-suppressant protein, is first manufactured now. Without EPF, your body might mistake the developing baby for a foreign body (like a bacterium or a virus) and attack it. With EPF, your baby can continue to develop without risk.
In the last twenty-four hours, the two identical cells have undergone three or four additional cell divisions. Two cells become four, four cells become eight, and eight cells become sixteen in a tightly packed, solid-ball configuration. Because the original cell is dividing into smaller units, there is little if any corresponding increase in your baby’s total size.
The ball of cells that was once the fertilized egg is still too small to be seen, but it will enter your uterus either today or tomorrow.
When the cell ball comes to rest on the surface of your uterus, the process of implantation begins. During implantation, the outer cells that have made contact literally fuse with the cells on the surface of your uterus. Implantation protects the cell ball and provides it with oxygen and nutrients from your blood stream.
Implantation continues. The actual size of the implanted cell ball is .004 of an inch (0.1 mm). Ten implanted cell balls could fit into the space occupied by this printed period: .
When implantation is taking place, the cell ball actually burrows into your uterine lining, displacing some of its tissue. As a result, you may notice some light spotting. Don’t mistake this spotting for a light menstrual period - it’s evidence that your pregnancy has begun.
