(bright upbeat music)
- It's implantation time!
Now, no bigger than a poppy
seed, but a whole lot sweeter,
the ball of cells that
will become your baby
has completed its week-long voyage
down your fallopian tube
and has claimed its berth in your uterus
by tunneling into the
sticky uterine lining.
Nestled in your uterine home,
this miniature miracle has established
the cozy connection that
will bind the two of you
for the next eight-plus
months and forever after.
But that's just the beginning
of the action this week.
In the works is the amniotic sac
that your baby will call home, sweet home,
and, at last, the sign
you've been waiting for.
Your little embryo starts to produce HCG,
the just-for-pregnancy
hormone that'll turn
your pregnancy pee test
positively positive.
You are officially expecting.
Though your embryo is only a tiny dot,
it has already stared to differentiate
into three layers, each
with its own job assignment.
The inner layer, called the endoderm,
will become the digestive
system, the liver,
pancreas, bladder and thyroid gland.
The middle layer, the mesoderm,
will grow into the heart, bones, kidneys,
muscles and blood vessels.
The outer layer, called the ectoderm,
will develop into the
brain, nervous system,
skin, hair and eyes.
It's hard to believe,
but by the end of your
fourth week of pregnancy,
all the building blocks
for baby's vital organs
are firmly in place.
(bright upbeat music)
