The cell by cell development of a baby in the mother’s womb is what is known as prenatal development. From just a single cell all the way to a fetus before birth. It takes an average of 38 weeks for the fetus to develop from the very date of conception. To become a baby the zygote will go through several stages. There are mainly three stages that facilitate this development.
Conception is the major process where the female egg meets the male sperm and is fertilized. Biology has it such that female only releases one egg each month although the male can release countless of sperms in one shot. The egg release process is known as ovulation. However, sometimes several eggs can be released at once from both ovaries. In other situations the woman may have several ovaries and they may all release an egg each. The fertilization of the egg can happen by the traditional method of sexual intercourse or by artificial insemination. After the release of the egg, the sperm must meet the egg in 12 hours because the egg will be destroyed after this time and ejected out of the body in the monthly process of menstruation. The outer membrane material of the egg is destroyed by fluids on the sperm, and the genetic material of the sperm and those of the egg combine to form and single cell that is known as the zygote. This single cell begins the first stage of pre-natal development known as the germinal stage.
Once the cell is formed, it quickly begins to divide to several parts. It will first divide into 2 identical cells. Those will divide to 4 cells then to 8 and so on. Thereafter, the zygote therefore begins to grow rapidly. Sixteen cells are already formed 60 hours after fertilization. When these cells attach to the walls of the uterus, another stage begins.
Even after implantation, the baby cells continue to divide and cluster rapidly. This stage lasts until 8 weeks after conception. The cells differentiate themselves depending upon the functions they perform. This differentiation will go one for weeks with more and more cells dividing and taking on different roles to help the baby develop nails, hair, blood cells, a heart and brain. By week four, the baby already has some facial structures formed and the limbs can be distinguished. Towards the end of this stage, all the major internal and external structures of the body have already been formed.
When the embryo develops to a fetus after 8 weeks, it is only 1.2 inches in length and only weighs about three grams. At this point most women do not even look pregnant. The fetus stage will last until the last day of gestation when the baby is born. At this time it will be approximately 3.3 kilograms and 20 inches in length. At this stage all the details begin to fill out. The fetus will develop a breathing system, sweat glands, skin and hair, eyelashes and eyebrows. They will also begin learning how to breath, sucking their finger and opening their eyes. Body fat will also begin filling under the skin which was mostly translucent.