The concept of fetal development is used to describe the development process of an embryo throughout pregnancy. Pregnancy is defined as the first 12 weeks of a woman’s life. In general prenatal development begins with conception, in which the female egg meets the spermatozoon and becomes pregnant.
Fertilization of an egg by a spermatozoon results in the release of an egg’s nucleus, or egg cell, into the ovary. The egg cell’s nucleus attaches to the uterine wall, where it can be deposited for implantation into the uterus. The uterine lining is covered in fluid, called the amniotic fluid. This fluid is produced primarily for the support of developing fetuses.
Fertilization of an egg by spermatozoon results in the release of an egg’s mitochondria, or DNA, from the egg cell. Mitochondrial DNA has a direct effect on the development and functioning of all cells but is also highly unstable in comparison with the DNA of an egg cell. As a result, the nucleus of an egg cell is only partially exposed and not completely functional. Fertilization of a spermatozoon with an X chromosome results in the release of a Y chromosome that will be responsible for developing the human body.
The development process of each individual fetus is determined by the timing and type of fertilization. If conception occurs early enough, the baby will have the possibility of growth and development as a developing fetus. This makes the process of implantation more rapid. This allows for a higher chance of survival after birth.
In most instances, if conception occurs late enough, a term fetus will be born and live for one to two weeks. The term fetus will be developed enough to develop some form of muscular coordination, including the ability to suck, walk, and breathe. A term fetus may also be capable of speech and may be able to articulate language, at approximately six months old. At approximately nine months, the infant will be able to move about and become mobile and adapt to its environment.
In most cases, the duration of time in which a term fetus remains alive is very short. It will not survive the past four weeks in most cases.
A preemie is a person who was born before the normal age of 21 weeks. Preemies are generally healthy, though they have less chance for normal development than normal babies. They are considered “preemies” because they are born too far along to be able to survive, or are born with disabilities that affect their development and ability to sustain life. Preemies usually need extra care after birth, to improve their chances of survival.
Some preemie babies will need intensive medical intervention after birth in order to achieve proper health. These babies have a longer and slower development process than normal babies. Some preemies may require surgery for deformity or permanent brain damage. Other preemies will require special care in order to increase their strength and improve their motor skills.
Once the baby has reached around nine months in age, the baby’s heart begins to pump blood. This is necessary for their health and well-being.
Throughout pregnancy, the fetus grows into the mother’s uterus and attaches itself to the placenta, a sac filled with a fluid called amniotic fluid. This attachment will continue until the baby is born. The placenta will then release a baby’s own blood supply. This is referred to as the mother’s blood. The umbilical cord will then attach to the baby’s back.
New born babies develop into toddlers and beyond. Hence, toddlers will begin to walk, crawl, and talk.
Toddlers begin to have more control over their movements and will be able to do a variety of tasks, like dress themselves. However, toddlers can even take care of themselves and play with other children. At around three years of age, toddlers may even be able to hold their heads up and sit up.