Prenatal development is the period from the time of conception until birth, when the egg germinates into fetus and finally turns into a new life. A child takes about 9 months or 40 weeks to reach the stage of birth. In this time period, it goes through lots of changes, the growth, during this time, being much more rapid and intense than after-birth developments. Prenatal development starts from the conception of the zygote and then goes through several weeks, before turning into an infant, weighing approximately 7 1/2 pounds and containing about 200 billion cells. All this occurs in a nine-month time period. The 40 weeks of pregnancy that a woman goes through, can be broadly split into 3 stages of prenatal development. During each of the stages, the child goes through different levels of growth and development.
Different Stages Of Pregnancy
Conception Stage
Conception occurs in the first two weeks of pregnancy. During this time, the body readies the womb for potential pregnancy by ramping up a layer of rich, blood-perfused tissue around the womb. The process of conception takes about two weeks, after which the egg reaches the uterus and evolves into a life. This stage is basically a preparatory stage that initiates the preliminary process and gears up the body for impending pregnancy.
Embryonic Stage
This stage starts when the egg reaches the uterus and lasts till the eleventh week of pregnancy. This stage is held as the most crucial leg of one’s pregnancy term, when the reproduction system undergoes crucial initial development and calls for great precautions. After the second week, the embryo germinates speedily and it is only in the fourth week that the cellular division starts. This is indeed a significant stage when the cell splits to create the placenta and the baby.
Around the sixth week, the baby acquires heartbeat and shows development of limbs too. This is one of the most significant stages of prenatal development. In the eighth week, the teeth and the intestines start developing. Towards the end of this significant prenatal stage, nearly all of the major organs of the body, including central nervous system, various joints of the body and the iris of the eye have developed.
Fetal Development
This stage starts from eleventh week onwards, when the child is called fetus. This is the last stage of prenatal development and ends with the birth of the child. From the eleventh week onwards, the fetus starts developing genitals, hair, nails, vocal chords, hardened bones. This is also the time when the liver and the kidney of the fetus start to function.
From the 16th week onwards till the 20th week, the fetus experiences rapid growth. This is the time when fat starts cumulating under the thin skin. It is also during this stage that the heart starts pumping more amounts of blood and the baby also starts experiencing hiccups. What more, this is the time when your fetus spends the same amount of time awake and asleep, as a typical newborn.
Fetal development, however, decelerates during the 21st to 24th weeks. By this time, the child’s eyebrows and eyelids are perfectly formed, and it usually weighs about 1.3 pounds. If the fetus is a boy, its testes begin to develop thence. Lung development starts during this phase and it begins to secrete surfactant, which is necessary for breathing. Brain development also takes place during this time. The baby’s retinas also begin to form, and it can open its eyes at this point.
By the 40th week almost all the major organs have formed, apart from the lungs. The child starts developing necessary immunities, and also starts fattening up, to deal with the outer environment. From the 37th week, the baby starts adding an ounce of weight per day to his/her total body weight. At the 40th week, the child is all set to be delivered.