Week 3

Conception or fertilization takes place when a sperm from the male fuses with the ovum to form a single cell that ultimately becomes your baby. This cell multiplies into over a hundred cells and travels along your fallopian tube until it reaches the uterus by approximately the fourth day after fertilization.

About thirty hours after fertilization, the fertilized cell divides into two, and ten hours after this it further divides into four identical cells, each getting smaller by each division. Within three days it has become sixteen in number as it continues its travel up the fallopian tube. On the fourth day the fertilized egg has multiplied into over a hundred cells and is still growing fast. The egg now has a fluid-filled centre but looks like a solid round mass as it enters the uterus. It is still invisible to the naked eye.

The blastocyst, as the egg is now called, is made up of two layers that eventually become the placenta and the embryo. It floats about in the womb getting its nourishment from the secretion of glands situated in the lining of the uterus. By the end of this week, it will attach itself to the thickening lining of the womb by a process known as implantation that signals the completion of conception.