Fetal Stage This stage is marked by amazing change and growth. The early body systems and structures established in the embryonic stage continue to develop. The neural tube develops into the brain and spinal cord and neurons continue to form.
Defining the Fetal Stage The fetal stage extends from the beginning of the ninth week after fertilization to about 38 weeks after fertilization, which is the average time of birth. The fetal stage lasts a total of approximately 30 weeks.
Gastrulation. Gastrulation is the process through which the bilaminar disk develops into a trilaminar embryonic disk. Gastrulation is the most important event of early fetal formation; it affects all of the rest of embryologic development.
During the fetal stage, the brain develops and the body adds size and weight until the fetus reaches full-term development. This video on prenatal development explains many of the developmental milestones and changes that happen during each month of development for the embryo and fetus.
In humans, an unborn baby that develops and grows inside the uterus (womb). The fetal period begins 8 weeks after fertilization of an egg by a sperm and ends at the time of birth.
During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote. Then the zygote travels down the fallopian tube, where it becomes a morula. Once it reaches the uterus, the morula becomes a blastocyst. The blastocyst then burrows into the uterine lining — a process called implantation.
Normal prenatal development lasts about 38 weeks and is divided into three stages: germinal, embryonic, and fetal. During these three stages of gestation, the original single-celled zygote develops into an embryo and then fetus [1, 2].
The Stages of Embryo DevelopmentFertilization. Fertilization is the union of the female gamete (egg) and the male gamete (spermatozoa). ... Blastocyst Development. ... Blastocyst Implantation. ... Embryo Development. ... Fetal Development.
In general, major defects of the body and internal organs are more likely to occur between 3 to 12 embryo / fetal weeks. This is the same as 5 to 14 gestational weeks (weeks since the first day of your last period). This is also referred to as the first trimester.
During the fetal period, the rate of growth slows as the infant prepares for birth. - functional development of the various organ systems as each system gradually begins working and then becomes more efficient in preparation for birth.
A fetus or foetus (/ˈfiːtəs/; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place.