prenatal stages
embryo
The developing ball of cells is now called an
implantation
Around seven days after conception, the ball of cells starts to become embedded in the wall of the uterus. This process is called
embryonic stage
In this stage, all the major organs form, and the embryo becomes very fragile
zygote
Conception occurs when a sperm cell combines with an egg cell to form a
placenta
One key feature of the germinal stage is the formation of a tissue called the
fetal stage
The last stage of prenatal development is
germinal stage
The two-week period after conception
prenatal period
This period is generally divided into three stages: the germinal stage, the embryonic stage, and the fetal stage.
Blastocyst
a hollow ball of about 150 cells
organogenesis
every major organ takes shape, in it's primitive form
implantation
fails, as is quite common, the pregnancy terminates.
embryonic stage
lasts from the end of the germinal stage to two months after conception
fetal stage
lasts from two months after conception until birth
embryonic period
occurs from the third to the eighth week after conception
prenatal period
the time between conception and birth
Miscarriage
spontaneous abortion that happens between 8% and 30%
twenty-two to twenty-six weeks after conception
the fetus reaches the age of viability
About thirty-six hours after conception
the zygote begins to divide quickly