Nova (1974–…): Season 28, Episode 17 - Life's Greatest Miracle - full transcript

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People do all sorts of things
to get attention.

And why?

It may be the last thing
on his mind

but this man's body
is working toward this.

Whether we're thinking
about it or not

our bodies want to make babies.

And our bodies
are very good at it.

Around the world, about 365,000
new babies get made every day.

But as ordinary as it seems

creating a new human being
is no simple feat.

Just think of it.



No matter who you are, once upon
a time, you looked like this.

From a single cell,
you built a body

that has 100 trillion cells.

You made hundreds
of different kinds of tissues

and dozens of organs

including a brain that allows
you to do remarkable things.

How did you do it?

Today, we can look closer
than ever before...

Into the womb...

into a cell...

into the essence of life itself.

Not only can we see
what's happening

but now, we're beginning
to see how it happens...

The forces that build
the embryo;



the molecules that drive
this remarkable change.

We're uncovering
the most intimate details

of how life is created...

The secrets behind
"Life's Greatest Miracle."

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You might think all the people
on this beach

are just working
on their suntans.

But beneath all that sunscreen,
under the skin

there's a frenzy of activity.

Without even thinking about it

almost all the adults here
are busy

trying to reproduce.

They can't help themselves.

The urge to procreate
is a fundamental part of life

not just for us,
but for all life.

Why is this urge so universal?

At least some blame
can probably go to this...

DNA, the molecule
that carries our genes;

the chemical instructions
for building our bodies

and keeping us alive

all wrapped up
in a tiny winding staircase.

DNA has run the show for more
than four billion years

for one main reason:

It's very good
at making copies of itself.

The copies can get passed
to a new generation

in a couple of ways.

If you're a bacterium,
you might be into cloning...

Making exact replicas
of yourself.

All your descendants
have the same DNA

and, except for an occasional
mutant, are just like you.

It's simple, it works

and genetically,
it's extremely boring.

It can also be dangerous.

If humans were all clones

everyone would have
the exact same immune system

and one successful parasite
could wipe us all out.

Fortunately, there's sex...

The method of choice for 99.9%
of the organisms on Earth

more complex than bacteria.

With sexual reproduction

two individuals
each provide some DNA.

Most animals put it
into sperm or eggs.

If the two can get together,
a new being will be created...

One that's different from
its parents and everybody else.

Where there's sex,
there's variety.

And when it comes
to survival of the fittest

variety has
a definite advantage.

All this comes at a price.

Sexual reproduction
may be popular

but it's also quite tricky.

To get an idea of how tricky

just take a peek
inside a man's testicle.

It's packed with tiny tubes,
coiled into bundles.

Stretched out,
they could cover half a mile.

Inside all this tubing,
the average man

is churning out a thousand
new sperm every second.

That's about a hundred million
new sperm every day

and more than two trillion
over a lifetime.

And here's the tricky part:

Each and every sperm
is one-of-a-kind...

Carrying a unique
genetic package.

How is this possible?

How can one person produce

so many different combinations
of genes?

The answer lies
in the very special way

we make sperm and eggs...

A process called "meiosis."

In almost every cell
of your body

you have 30,000 or more
different genes

spread out on very long strands
of DNA, called "chromosomes."

Most cells have two versions
of every gene

on a total of 46 chromosomes.

Exactly half of those, 23,
came from your mom

and 23 came from your dad.

They come in pairs, where
the partners are very similar

but not quite the same.

The only time they get together
is during meiosis.

Here's how it works inside
a testicle that's making sperm.

First, each chromosome makes
an exact copy of itself

keeping it attached
at one point.

They condense,
creating an X-shape.

Now, the chromosome partners
get together

and the two, or actually four,
will embrace.

They cling so closely

big chunks, carrying
whole bunches of genes

get exchanged
between the partners.

The cell then divides twice

each time pulling
the pairs apart.

The final result
is a sperm or an egg cell

with 23 chromosomes,
half the normal number.

By itself,
the cell is incomplete

but it still holds
incredible promise

because every chromosome now
carries a combination of genes

that has never existed before.

All this gene-shuffling means
that within a single species

there can be an enormous amount
of diversity.

And the more diversity,
the better the odds are

that someone will survive
to create a new generation.

This is my mom and dad
on their wedding day.

My mom and dad
on their wedding days.

You definitely have

your mom's eyes.

You can see I definitely have

my dad's eyebrows.

You do have your dad's eyebrows.

Melinda Tate Iruegas
and her husband, Sergio

are expecting their first baby.

Here's Mom and Dad
with me and my brother.

Oh, yeah.

My sister hadn't come along yet

but this is what
our little boy
might look like.

Their unborn child
carries a mixture of genes

not just from them,
but from all their ancestors.

Looks like the spitting image.

Mm-hmm.

You look so much like
your mother here.

But which genes got passed on
from whom

right now is anybody's guess.

Because here you are

and this is what
our little girl
might look like.

I wonder if the baby will have

the characteristic eyebrows

that comes from my father's
side of the family.

We call them
the Iruegas eyebrows.

Or that it won't
have my dad's nose.

Your nose.

It's a beautiful evening.

We talked about having children
a lot.

He's been saying,
"Five, six," you know

and I was, like, "Well,
let's start with one."

Yeah.

"You know, two,
maybe three."

and the baby likes the water.

Yeah.

In their efforts
to pass on their genes

Melinda and Sergio

pursue dramatically
different strategies.

I can't wait
for the baby to come.

Like most men

Sergio has been constantly
producing sperm since puberty.

But Melinda created all her eggs
when she looked like this...

A fetus in her mother's womb.

Within a couple of months, she
created several million eggs.

And then, the eggs began to die.

At the age of 31, Melinda may
only have a few thousand left.

But that's okay,
because inside an ovary

as opposed to a testicle

it's quality, not quantity,
that counts.

Every month,
one of a woman's two ovaries

selects an immature egg cell
to lavish with attention.

Hundreds of support cells
tend the egg

feeding it until it grows fat.

When it's ready,
the whole entourage...

The egg along with its helpers...

Oozes out of the ovary.

Waiting for them is the open end
of the Fallopian tube

which leads to the uterus.

Its tentacles capture the egg
and pull it inside.

The egg is swept along

by muscular contractions
of the tube

as well as the constant swaying
of tiny cilia.

The egg has everything it needs
to start a new life

except for one thing,
DNA from a sperm.

And it has to get it fast.

If the egg is not fertilized
within a few hours, it will die.

With sex,
there will always be pressure

to meet and impress a mate.

When it comes to actually
choosing a partner

there's a lot to consider.

For us, it might be somewhat
more complicated

than picking the one
that smells best.

But there's no doubt
that the process

can be heavily influenced
by chemistry...

Natural drugs
that flood the brain.

♪ Mi amor,
mi amor, mi amor... ♪

♪ Mi amor,
mi amor, mi amor... ♪

♪ Mi amor, mi amor,
mi amor! ♪

When love is in the air

the body can undergo
some dramatic changes.

Signals from the brain speed up
the metabolism of glucose.

As a result, body temperature
rises, skin sweats

heartbeat and breathing
get faster.

In a man, hormones cue blood
vessels to relax

allowing the spongy tissue
in the penis to fill with blood.

At the height
of sexual excitement

millions of sperm
are squeezed out of storage

and swept up by fluid
gushing from several glands

including the prostate.

The flood carries them
into a 15-inch-long tube

looping into the abdomen
and then out through the penis.

It's only about
a teaspoon of liquid

but it typically contains
about 300 million sperm.

They are immediately in peril.

The vagina is acidic,
so the sperm must escape or die.

They start to swim...
at least some of them.

Even in a healthy man

60% of the sperm
can be less than perfect

like this one with two tails.

For these guys,
the journey is over.

But what about the rest?

What are the chances

that one tiny sperm will
reach and fertilize an egg?

Sperm are often portrayed
as brave little warriors

forging their way
through hostile terrain

to conquer the egg.

Nothing could be
further from the truth.

For every challenge
the sperm face

success is, to a great extent,
controlled by the woman's body

and even the egg itself.

Take the sperm's
first obstacle, the cervix...

Passageway to the uterus.

Most of the time,
it's locked shut

plugged with mucus that keeps
bacteria and sperm out.

But for just a few days
a month around ovulation

the mucus becomes watery

and forms tiny channels
that guide the sperm through.

Arriving inside the uterus

the sperm are still about six
inches away from their goal...

At least a two-day swim.

But undulations
of the uterine muscles

propel the sperm
into the Fallopian tube

within 30 minutes.

Even a sperm that reaches
the tube in record time

has no guarantee
of fertilizing an egg.

There may be no egg there.

Ovulation could still be
days away.

It's the slowpokes... caught up
in the cilia lining the tube...

Who may have a better chance.

It's probably here that
chemicals in the woman's body

alter the sperm's outer coating.

Only those sperm
that are altered

can get a date with the egg.

The sperm are released gradually

over the course of a few days,
so at any given time

only a couple hundred sperm
will move on.

If all goes well

then farther up the tube
they'll find the egg.

But it's heavily chaperoned
by support cells

and the chaperones are picky.

Only some of the sperm
are let through.

Those who make it will face
yet another challenge.

Underneath the cloud of cells

the egg itself is encased
in a thick protein shell

called the zona.

To fertilize the egg, the sperm
must break through the zona;

but even the strongest can't
do it by brute force alone.

The egg demands
a proper introduction.

Proteins protruding
from the sperm's cap

must hook up precisely
with a set of proteins

on the egg's surface.

If they match,
the sperm is held fast

and undergoes
a dramatic transformation.

It sheds its outer coating,
releasing powerful enzymes

that dissolve a hole in the zona

allowing the sperm
to push its way through.

The final hurdle passed

the sperm still does not thrust
its way into the egg itself.

Rather, the membranes
of the two cells fuse

and the egg draws the entire
contents of the sperm inside.

I don't know.

We weren't being as careful

as we should have been

and October came around

and I was a day late

and actually I was having

some other problems,
with my wrist.

And we went to the doctor

and the doctor had asked me

was, like, "Well,
are you pregnant?"

you know, because
he wanted to do

an X ray of my wrist.

And I said, "No."

And then I thought about it

and I was, like,
"Well, I don't know."

I decided that I
better check this out.

And sure enough,
it was positive.

And when he came home,
I was like...

I could tell she had
something to tell me.

And, um...
so, I was, like

"Well, you'd
better sit down."

You just...

It was something
that we had discussed

but hadn't anticipated

until about two more years
down the road.

So when she told me,
yeah, I was ecstatic.

We were ready.

We were definitely ready

even if it was a little early.

Ready or not,
once sperm and egg get together

they have their own agenda,
to create a viable embryo.

Their chances aren't great.

It's estimated

that more than 50% of all
fertilized eggs fail to develop.

If it's going to survive, the
egg has a lot of work to do.

First, it orders the zona
to lock out all other sperm.

And then the egg
must finish meiosis

expelling half
of its chromosomes

into this tiny pouch,
called a polar body.

With the door closed behind it

the single sperm already inside
releases its precious cargo.

The sperm's 23 chromosomes
stretch out

in the roomy, welcoming egg.

The chromosomes of sperm and egg
approach each other

and then the cell divides.

Since the moment the sperm
entered the egg

24 hours have passed.

All this time

the fertilized egg is moving
down the Fallopian tube

toward the uterus.

Every few hours,
the cells divide...

Four...

eight...

sixteen...

gradually creating
the building blocks

needed to construct an embryo.

On rare occasions

the tiny cluster of cells splits
into two groups

and creates two embryos,
identical twins.

But most of the time,
the cells stick together.

They must complete just the
right number of cell divisions

before they arrive in the uterus

about five days
after fertilization.

What started
as a large, single cell

has divided into just over
a hundred much smaller cells.

But they're still trapped within
the hard shell of the zona.

Now called a blastocyst

the bundle of cells
must do two things to survive:

break out of the zona and find
a source of nourishment.

At the beginning of the sixth
day, it orchestrates an escape.

It releases an enzyme
that eats through the zona

and the ball of cells
squeezes out.

Free at last,
the blastocyst lands

on the blood-rich lining
of the mother's uterus.

It has just passed one hurdle

but is immediately presented
with another.

For, in fact, it is now
in very grave danger.

Stripped
of its protective coating

the blastocyst could be attacked
by the mother's immune system

as a foreign invader.

White blood cells
would swarm in to devour it.

In its own self-defense

the ball of cells produces
several chemicals

that suppress the mother's
immune system inside the uterus

in effect, convincing
the mother to treat it

like a welcome guest.

Then it is free to get to work.

Searching for food and oxygen

cells from the blastocyst
reach down

and burrow into
the surrounding tissue.

Eventually, they pull
the entire bundle down

into the uterine lining...

And sooner or later,
the mother will notice.

Even brushing my teeth
would make me...

the minty flavor
was just, like, gross

and make me feel nauseous.

And I would get up

and I would try to eat something

and if anything smelt...
off slightly

then it was...
it made me nauseous.

My mother has told me stories

of how my father had gone
through morning sickness.

And, of course, that never
really registered

until the first time
it started happening to me.

He literally got...

He would get really,
really nauseous
and upset

and actually get
physically ill
sometimes.

There was a couple
of times when that...

well, more than
a couple of times

when that actually happened.

Not everybody
gets morning sickness.

Sometimes months can go by

before the mother gets any sense
of the drama

unfolding within her body.

One milestone event takes place
just two weeks after conception

when the blastocyst is about
the size of a poppy seed.

This is the moment

when the cells start to organize
themselves into an embryo.

The process
is called gastrulation.

With animals like frogs

whose embryos develop
inside transparent eggs

it's easy to see it in action.

After the egg becomes
a hollow ball of many cells

some cells dive into the center,
forming layers

which will go on to develop
into different organs.

In humans, gastrulation happens

deep inside
the mother's uterine lining

so it can't be photographed.

But we think it works
something like this.

The blastocyst
creates two oblong bubbles

one on top of the other.

Sandwiched between them
is a thin layer of cells.

These are the cells
which one day may become a baby.

At the beginning of gastrulation

some cells begin moving
toward the center.

Then they dive downwards,
creating a new, lower layer.

More cells plunge through

squeezing in between,
forming a third.

The cells in the three layers
may not look different

but for each layer, a very
different future lies ahead.

The lower cells are destined
to form structures

like the lungs, liver and the
lining of the digestive tract.

The middle layer will form the
heart, muscles, bones and blood.

And the top layer
will create the nervous system

including the spinal cord
and the brain

as well as an outer covering
of skin, and eventually hair.

This is a human embryo
three weeks after fertilization.

Less than
a tenth of an inch long

its neural tube, the beginning
of the nervous system

is already in place.

A couple of days layer, the top
of the tube is bulging outwards

on its way to becoming a brain.

With the primitive
brain cells exposed

we can see
some are sending feelers

making connections
to their neighbors.

As the days pass, changes
proceed at a rapid-fire pace

throughout the embryo.

Everywhere,
cells are multiplying.

And they're on the move.

Some reach out to one another,
forming blood vessels.

A heart begins to beat.

As the embryo lengthens, the
precursor to the backbone forms.

Groups of cells
bulge out on the sides...

The beginnings of arms and legs.

This is the embryo
4½ weeks after fertilization.

It is only
about a fifth of an inch long.

The primitive backbone
now curls into a tail

which will disappear
in a few weeks.

A large brain is developing

and on the side
of the head, an eye.

How does this happen?

How does the embryo
transform itself

from a blob of cells

into different tissues
and organs

and finally into
a fully functional baby?

The secret, of course,
lies in your genes, in your DNA.

Inside most every cell
in your body

you have the same 46 chromosomes
carrying the same genes.

But not all the cells
in your body are the same.

Nerve cells...

blood cells...

cells lining your intestine...

they all look different
and they do different jobs.

That's because
in each of these cells

different groups of genes
are turned on

and when a gene is turned on

it tells the cell to construct
a particular protein.

Proteins are the molecules
that build your body...

Like collagen,
a fiber that makes up

much of your skin,
tendons and bones.

Or keratin in your hair.

Crystallin is the protein

that helps make the lens
of your eye clear.

Some proteins do work;

actin and myosin
move muscle fibers.

Hemoglobin in the blood

carries oxygen from the lungs
to the rest of the body.

So when the embryo is developing

how does a cell turn on
the right set of genes

and create the right proteins?

Part of the answer
seems to be... location.

Once the basic body plan
is established...

With a head on one end,
back and front

and left and right sides...

Cells seem to know
exactly where they are

and what they
are supposed to become.

This is because
cells talk to each other

in the form
of chemical messages.

Chemicals in one cell
can trigger a reaction

in the cell next door

that can spread
to the cell's nucleus

and turn genes on or off.

But what's really
going on in there?

How does a gene get turned on?

If all the DNA in a single cell
were stretched out

it would be about six feet long

but it's all wound up
very tightly

coiled around balls of protein.

For a gene to be turned on

something has to come in
and loosen up the right section.

Then, the cell's machinery
can latch on and read the DNA

the first step on the long road
to building a protein.

Those molecules
that can turn genes on

play a key role
in every aspect of development

including the process

that transforms the embryo
into a boy or a girl.

We didn't want to know.

We wanted to do it,
I guess, the old-fashioned way.

Well, you kind of wanted
to know.

We did a wedding-ring test

where you took
a piece of your hair

and the wedding band,
and you hold it over the belly

and if it moves one way
in a circle, then it's a girl

if it moves in a straight line

it's a boy.

And that said it was a girl.

And there was a point
when we went into the ultrasound

where I was waffling.

It was, like,
"Well, we could look.

"At this very moment
we could look

and we could find out,"
and I didn't say anything.

See, but I was
trying to be strong

because she was
very adamant about not...

I said, "No, no, no."

By the time
most ultrasounds are done

around 18 weeks or so, doctors
can sometimes make out the sex.

But in the early weeks,
it's impossible.

Take a look
at a seven-week-old embryo.

Try to guess what sex it is.

Think it's a boy?

Believe it or not, this is not
a penis... at least not yet.

It might become one

but it could just as easily
turn into a clitoris

the female sex organ.

At this stage, boys and girls
look exactly alike.

And not just on the outside.

Inside, there are two gonads

which could become testicles
or ovaries.

And there are two sets of tubes:

one in case it's a boy,
the other for a girl.

Of course, there is one way
to tell the difference...

Look at the chromosomes
in a cell from the embryo.

One pair among the 23
determines sex.

An embryo with two X chromosomes
usually becomes a girl.

If one of those Xs is a Y,
it will most likely be a boy.

Recently scientists came up with
a good idea of how this works.

There are only about 30 genes
on the Y chromosome.

One of them is called SRY.

This gene seems to function
just once in a lifetime

late in the sixth week
of embryonic development

and only in one place:
the gonad.

SRY turns on for a day or two

and the cells
churn out its protein.

But in that short time

SRY sets off
a chemical chain reaction

turning on other genes

eventually turning the gonads
into testicles

which begin
to make testosterone.

Testosterone travels
throughout the body.

If it reaches the genitals

then the cells here
will build a penis.

But if there are two
X chromosomes and no Y

different genes get turned on,
and the gonads become ovaries.

The embryo becomes a baby girl.

This is the power of genes...

Creating cascades
of chemical reactions

defining the form and function
of all the cells in your body.

Sometimes genes send the message
to multiply and grow

as with the arm and leg buds.

Sometimes the message is to die

as it is a few days later, to
the cells between the fingers.

As the weeks pass

the embryo's genes send
billions of individual messages

constructing new kinds of cells
and building organs and limbs.

Two months after fertilization

the embryo
is now called a fetus.

Almost all its organs
are in place

though they're not working yet.

The whole fetus
is just over an inch long

and weighs less
than a third of an ounce.

Over the next 6½ months

it will grow
almost 400 times larger

and prepare for birth.

All of this demands
a constant supply of nutrients.

Serge was a little frustrated

because he thought he was going

to be able to go out and get me

whatever I craved
and whatever I wanted

and I had the problem

of I didn't want anything

or crave anything
until I smelled it

and I had to smell my food

before I would eat it.

I could cook a whole meal

and if it didn't smell right

when I was done
with it, you know

just because I put
the wrong spice
in there or something

then I couldn't eat it.

Well, what about
this place here?

Let's check out the menu.

Mmm... no.

No?

No.

We would go out on walks

sometimes just
around in the square.

What do you think?

No, It's not going to work.

She would
have to smell it first.

Just see what
caught her fancy at that time.

Yeah.

Yeah?

As soon as it did

then that's where we would go.

And that lasted
throughout my entire pregnancy.

How is it?

Garlicky, yum.

Baby likes it?

Yeah, I'm pretty hungry.

I'm still like that.

I still really
want to smell my food

and if I smell something
and I'm just, like

"Oh, I have to have that,
and I have to have it now."

It's no surprise that Melinda
might be especially hungry.

The fetus she's carrying
has only one source

for all the raw materials
it needs to grow into a baby...

Melinda's blood...

Which is systematically raided
with the help of the placenta.

The placenta began to form

as soon as
the blastocyst burrowed

into the mother's uterus

and in the early weeks,
it dwarfed the embryo.

The underside of the placenta

is covered with thousands of
tiny projections, called villi

which lie in pools
of the mother's blood.

Without ever mixing
the blood of mother and child

the villi grab oxygen
and nutrients.

The enriched blood flows
about a foot and a half

through the umbilical cord,
back to the fetus

whose heart beats about twice
as fast as an adult's.

The heart is one of the few
organs that actually work

during the earliest weeks
of development.

But with other organs,
function comes later.

With the eye

although the retina and lens are
well formed by the ninth week

the fetus doesn't respond
to light

until the fifth or sixth month.

And the same for the ear.

The outer ear
quickly takes shape

but the fetus can't hear yet.

Sound conduction relies on
the tiny bones of the inner ear

and most of the bones in the
fetus start out as cartilage.

By the fourth month, hard bone
can be seen forming in the hand

and the leg.

Finally, after five months

the process is complete
in the inner ear.

And then, the fetus
begins to hear sound.

I would sing songs
right on her belly

just so that it could hear
my voice

and get to know my voice,
but there was...

And what else?

And make whale noises.

Yeah.

One of the first times
I did that

the baby seemed to move

its hand across her belly,
and kind of touch my lips

or at least I like
to think it was a hand

saying hello or something.

And I even play music.

You know, I
wanted to see
what would happen

to what different
kinds of music.

And, you know, Mozart,
it, you know, was mellow

kind of made some movements.

And then I put salsa music in

and it just started
kicking, almost
in rhythm.

So, it was great.

Got a particular beat
that it likes.

Yeah.

There's three of us dancing.

This is the baby moving.

Inside Melinda's belly

a remarkable transformation
has taken place

starting with the moment
egg and sperm met.

Inside the womb, the first weeks
are the most dramatic.

Later in pregnancy

when the mother's body seems
to be changing the most

life in the womb can appear,
well, a bit uneventful.

All the organ systems are
in place

so during the last trimester,
the fetus's main job is to grow.

But a few crucial events are
unfolding beneath the skin.

Fat deposits are forming

building reserves the baby
will rely on after birth.

But even more importantly

fat is getting laid down
in the brain.

In the sixth month, genes in
the brain order the manufacture

of a fatty substance
called myelin

which wraps around the long
connections between brain cells.

This fatty covering allows
nerve impulses to travel

up to 100 times faster,
greatly enhancing brain power.

The process will continue for
years after the baby is born.

Inhale... come up.

The brain's hunger for fat
in the last trimester

puts an enormous strain
on the mother.

Inhale.

Over the course of the pregnancy

her body has increased its own
blood supply by about 50%...

All for the sake
of the rapidly growing baby.

But late in pregnancy

the baby's need for fat
becomes so great

the mother can't keep up.

If it stays inside,
the baby will begin to starve.

Somehow, it's got to get out.

It's climbing back up now.

I've only had, like,
one anxiety attack

and it was the moment
I was in the bathroom

and I just had
the thought of, like

how's this baby
going to get out?

I just don't think
he's going to make it out.

And I hadn't really thought
about it

up until that very moment,
where I was just, like, "No."

I love you.

Giving birth is one of the most
amazing experiences

a woman can have.

It can also be
one of the most painful.

Yeah, it's starting to go down.

Remember?

Think about being
in that garden.

Again and again,
the uterus contracts

as the cervix opens up.

The tiny passageway
that once allowed

the entrance of a single file
of sperm

must now widen
to about four inches

to accommodate a baby's head.

Human births are
far more dangerous

than those of other mammals,
or even other primates.

The human brain is three
to four times bigger

than an ape's brain.

And the pelvis is narrower,
to allow us to walk upright.

A human baby has to go through
considerable contortions

to make it through
the narrow opening.

Sometimes, there is simply
not enough room.

If that happens today

Melinda's baby can be delivered
by Cesarean section.

But not long ago, before
the rise of modern surgery

death was a common outcome
for the baby and the mother.

I can't help but feel
a little guilty

that I'm responsible for this

but it's part of the natural
cycle of life

and I just want to be there
in any way that I can

to support her
through this whole process.

Because of the pain and danger
of human labor,

we regularly give birth
in the presence of others.

Today, at 4:25 a.m., Melinda's
parents, along with Sergio

will have the privilege
of witnessing firsthand

this extraordinary event...
Life's greatest miracle.

Good job, good job.

Good job.

Can you get another breath?

Terrific.

Yeah, grab it again.

Oh, that's excellent.

One more time.

Quick breath and
push it right down
some more.

Oh, good, good, good.

Good job.

Okay, stop.

Here we come!

A life! A new life!

Here we go!

4:25.

All right!

A little boy!

Hey, we have a new sound!

Look.

Look at our little boy.

Hi, sweet pea.

Hi.

Isn't he adorable?

How are you?

Look how handsome you are.

You're so handsome, mm-hmm.

We've been wondering
who you were.

Yeah... yeah,
we've been playing
with you.

Hi.

Oh, there you go.

I love that little yawn.

Wake up.

On NOVA's Web site,
follow along in real time

as an expectant mother
chronicles

the joys and challenges
of her last months of pregnancy

and the birth of her baby

NOVA is a production
of WGBH Boston.

Major funding for NOVA is
provided by the Park Foundation

dedicated to education
and quality television.

Science.

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to help make wireless
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