(sweet upbeat music)
- It's a landmark week for your little one
since most of his key body systems
and vital organs are fully formed by now.
Your baby will spend the
rest of his gestation
bringing those systems up
to speed and full maturation
so they'll be able to function
to perfection once his
big birthday arrives.
Your fetus can now boast the achievement
of having more than doubled
in size in just three weeks.
Crown-to-rump length is
about two-and-a-half inches
so he's about the size of a
kiwi, but weighs a lot less.
Just half an ounce.
A fair amount of heft is in that crown.
Basic brain structure is complete
and now it's time for that
brain mass to rapidly increase.
Your baby's thyroid is now fully formed,
the pituitary gland has
started producing hormones
and the pancreas has begun
to synthesize insulin.
Not to be outdone, your baby's bone marrow
is churning out white blood cells,
the critical weapons
needed to fight infection
once your little warrior is on the outside
and no longer protected
by your immune system.
Muscles in the digestive
tract are getting primed,
practicing their contractions
so they can process food
and lots and lots of poop after birth.
And even though much
of the small intestines
are still folded up and
stored in the umbilical cord,
the villi, tiny finger-like projections
that absorb nutrients from
food, are now in place.
The best development of all:
if you haven't already heard it,
this is the week that
your cutie's heartbeat
will come through loud
and clear at your checkup
and that'll be music to your ears.
(upbeat music)
