What is the term used for new human life after fertilization?
embryo
You go from ovum (egg) + sperm and get a zygote. A single
fertilized cell. This divides rapidly forming a blastocyst. The
blastocyst has a few parts even though it is a tiny ball of cells.
One part will eventually form the placenta and the other part,
called the embroblast. At this point the baby-to-be has not
implanted, that is, it has not reached the uterine cell wall to
initiate pregnancy. The cell could easily die on it's own at this
stage, the mother-to-be is not considered pregnant either. Her body
is not yet hosting or contributing anything to the growth of the
blastocyst. When the blastocyst implants it will grow a placenta
that gets nutrients from the (now pregnant) mother and uses her
blood stream to eliminate waste. Now we have an embryo. The term
embryo can be used to describe this whole period from first
fertilization to eight weeks of pregnancy. But, the moment of
implantation is just so important to the whole process that I think
the distinction should be made. After eight weeks of pregnancy you
have a fetus and after birth you will have an
infant/newborn/baby.
Hope this helps,
D