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[205 The Course of Labor]
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[Narrator:] Toward the end of pregnancy,
as you wonder whether to get ready for a baby girl
or a baby boy,
nature is awaiting the precise moment
to start the birth process...
a process which is called labor.
Since the signal that things are starting may be
only a slight twinge,
some understanding
of the process of labor will help you
recognize when true labor is underway
and what takes place during the hours that
follow as your baby is born.
The word "labor" is also used to describe
the work of your uterine muscles as they contract
during the birth process.
Some call these contractions labor pains and vice versa.
Some call pains contractions.
Throughout pregnancy, your uterus or womb
has served to contain your growing baby.
The lower portion or cervix has been sealed with a mucous plug.
Inside, the sac of amniotic fluid
has cushioned your baby, whileyour placenta and umbilical
cord have nourished it.
When labor starts, the uterine muscles
above your cervix that have been stretched around your baby
will start to contract back toward normal.
These contractions provide the major work force needed
to give birth to your baby.
But several weeks before this happens,
your baby gradually moves downward
into a more favorable position for birth.
This change is called dropping or lightening.
You'll be able to breathe easier,
since there is more room for your diaphragm.
However, because of the increased pressure
of your baby on your bladder,
there is a tendency for you to urinate smaller amounts more often.
During the same period, you may be
more conscious of cramp-like pains
in the lower part of your abdomen or groin.
These are the same contractions that you normally
feel throughout pregnancy,
only now
they're likely to get stronger, and they may be painful.
But remember, if your contractions have
no regular pattern, and even if they last for a few hours,
if they go away, they were false labor pains.
Yet, these contractions are useful,
nature's way of softening your cervix
and getting your uterine muscles ready for the task ahead.
Then when the actual birth of your baby
is near, and probably at a time when you least expect it,
true labor will begin. Meaning that the birth
process has begun.
Yet, occasionally, there are certain clues
that labor is about to start.
You may notice a discharge of blood-tinged mucus
from your vagina.
This bloody show usually means that labor will
begin within the next 48 hours.
Sometimes, the bag of waters breaks
before the start of labor.
Anything from a gush to a steady trickle of fluid
must be reported with the expectation
that you will be going to the hospital.
But what usually happens first are the true pains of labor.
How can you recognize true labor?
The answer is that time will tell.
The first pains may be centered low in the back
or resemble menstrual cramps.
But unlike false labor, the pains do not go away.
Instead, they become progressively stronger,
more regular, and more frequent.
Therefore, it is important that you time your contractions.
Do not guess.
Use a watch with a second hand, and write down
how long each pain lasts and how far
apart the pains are so you can report
this information accurately.
For practical purposes, if your pains are strong,
last 30 seconds or longer, and occur regularly
eight to ten minutes apart, you may be reasonably sure
true labor is underway.
When you are told to leave for the hospital,
do not eat or drink anything.
Your stomach should be empty during labor and delivery
as a precaution against vomiting or other complications.
Although every woman has a slightly different story
to tell about her experience, the course of labor,
once started, continues involuntarily
through three stages.
The first stage of labor dilates or opens
the cervix in preparation for delivery.
If this is your first baby, this may
take from eight to 14 hours, during which time
your contractions get progressively
stronger and closer together.
The second stage of labor delivers the baby.
This may take an hour or more.
The third stage of labor expels the placenta, or afterbirth,
and this rarely takes longer than 15 minutes.
To complete the first stage of labor,
certain things must take place,
even though they may occur at different times
for different women.
The upper portion of your uterus becomes the active
contracting portion, and your cervix becomes passive.
As the active portion contracts,
it pulls or takes up the lower portion.
Gradually, as your cervical canal
is shortened and thinned out, a process
known as effacement, the mucus that has been sealing off
your cervix is dislodged.
Once the cervix is effaced and there is no longer a canal,
the external opening left in the membrane
begins to enlarge or dilate.
Within a short time, the dilatation
reaches about four inches, and your cervix
ten forms a smooth passageway with your vagina.
If your fluid-filled sac or bag of waters hasn't already
broken, it will usually rupture or be broken at this time,
and you'll feel a clear warm fluid pass from your vagina.
With the cervix dilated and the fluid in front of the baby's
head lost, your baby can then begin
the beautifully coordinated movements
of the second stage of labor.
It is during this stage that you will bear down,
that the muscles of your abdomen, as if by reflex action,
will help with the delivery.
Following its engagement within your pelvis,
your baby's head flexes forward to where
its chin rests on its chest.
Then each aspect of the descent is characterized
by the baby's head shifting or turning
to conform to the shape of your birth canal.
Molding of the head is possible because the bones of the skull
have not yet united and can therefore overlap
or compress during the descent.
As labor progresses, the back of your baby's head
pivots under your pubic bone,
which serves to extend it upward toward your vaginal opening.
Finally, your vulva bulges, then parts, and the head is born.
Within the next minute or so, the head and body turn,
the uppermost shoulder slips from under the pubic bone,
and the rest of the body is born.
While the umbilical cord is cut, the placenta or afterbirth
remains in the lower part of the uterus waiting
to be expelled during the third stage of labor.
Although the active portion of your uterus
has shrunk to almost a solid mass of muscle
around the placenta, there continue
to be mild contractions.
Once separated from the uterus, your placenta,
aided by slight pressure on your abdomen,
passes from your vagina to complete the birth process.
For the next few days, your uterus
can be felt as a hard mass in the lower abdomen.
Then during the next six weeks or so
it shrinks from an organ about the size of a grapefruit
to that of a small pear.
And, of course, one of the nicest things
about getting back to normal is getting back to a flat tummy.
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