Download Vaginal Birth After Cesarean Section: A Serious Decision, Are You

Vaginal Birth After Cesarean Section: A Serious Decision, Are You Ready to
Make It?
A Guideline Paper for Women
Madeline Burford
Fall 2004
A paper for Women’s Health Magazine
Introduction:
Giving birth is a very delicate and miraculous event, especially if you have had a
previous cesarean section and are making the choice to give birth vaginally. You are responsible
for bringing another life into this world to raise and have become an amazing person. The
decision to do so should be of the utmost importance to yourself and your partner. If you are in
this same position, this article will be a great help to you and your decision in your life and your
unborn baby’s life.
Picture this: a 26 year old woman is pregnant with her second child and had delivered by
cesarean section with her first child because of complications. For this pregnancy she wants to
research all of her options for delivering vaginally because she wants to experience a natural
childbirth. She heard that there were some dangers for both herself and her unborn baby in
making this decision. She is most concerned with researching all of the information involved
with uterine rupture because this is the most severe birthing difficulty.
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While giving birth, there is always a slight possibility that there will be complications.
One of the methods that doctors use to make sure the mother and baby are safe is a cesarean
section. If a mother has a cesarean section and then chooses to deliver vaginally, there is a
chance that the mother can experience a life threatening complication termed a uterine rupture.
There is a specific term for this method of delivery and that is VBAC. VBAC is short for
vaginal birth after cesarean section. “The most feared complication of pregnancy and labor in
women with previous cesarean delivery is uterine rupture, with the maternal and fetal morbidity
and mortality it entails” (Sen, Malik, Salhan, 2004). A uterine rupture is defined as a separation
of the entire thickness of the uterine wall in conjunction with cesarean delivery for suspected
fetal distress, extrusion of any portion of the fetal-placental unit, intra-peritoneal or vaginal
hemorrhage, need for hysterectomy, or bladder injury (Chauhan, Martin, Henrichs, Morrision,
Magann, 2003). The reason that uterine rupture is defined as in conjunction with cesarean
delivery is because all the research performed to date states that the majority of uterine ruptures
happen after a previous cesarean section.
The issues being discussed are based for the benefit of women who have already
experienced a cesarean section and who want to give birth vaginally in their next pregnancy
(VBAC). These issues raise many questions within the scientific community and the general
population because there is not enough research performed. The decision is yours and your
partner’s to make, but now there are hospitals that no longer will allow VBACs because of what
may happen. Also, uterine ruptures have been a rare occurrence in the past, but are now
becoming more common. The United States had a greater probability of uterine rupture when
comparing to other countries (Chauhan et al., 2003). In the years between 1996 and 1999
vaginal birth after previous cesarean delivery rate decreased from 28% to 21% (Harer, 2002).
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Because of the devastating effects, I want to build awareness to educate women and their
partners in this position. You, as a couple, have the right to make an informed decision when
dealing with such a delicate situation.
Figure 1:
Total Cesarean and VBAC Rates
30
Percent per 100 births
25
20
VBAC rate
15
Cesarean rate
10
5
0
1970
1975
1980
1985
1990
1995
2000
Year
Figure 1 shows the rates of both VBAC and cesarean sections with in the United States
between the years of 1970 through 2000.
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The decision to experience a VBAC is ultimately a choice that you and your partner will
make along with in put from your physician. The choice made will be after examining all of the
risks associated with VBAC for your certain situation. The best way for you to make this
decision is to be educated about all of the risks.
Research claims the contributing factors to this life threatening occurrence are the size of
the hospital because of its’ resources, the condition of the scar tissue, the condition of the fetal
heart rate (FHR), inter-delivery interval, and the use of prostaglandins to induce labor. The focus
on these particular issues is to inform and educate women and their partners of the possible
dangers and their importance. It is your choice. So ultimately, I am presenting specific
guidelines with the information up to date to assist you and your partner in making an educated
decision when it comes to deciding between VBAC or in having a repeat c-section and you can
research further to decide where you want to give birth. The guidelines presented within this
discussion are listed in order of importance of awareness to you and your partner.
Pregnancy can be a very stressful time for the mother and her family. While in labor, the
stressfulness can escalate because of all of the possible risks that can take place. My mother, as
well as other mothers, has told me what the mood is in the delivery room. They said that it is an
indescribable feeling, but the worrying feelings become greater in such a situation. I can only
imagine these feelings, but the reason for this particular article is to give you some confidence
with your own knowledge when entering this stressful situation. I want you and your spouse to
realize what is going on around you, so you can feel a little more comfortable with your educated
decision and your doctor’s.
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First Guideline: Size of the Hospital
This specific argument contributes to a greater chance of perinatal death due to uterine
rupture because the size of the hospital correlates with the number of resources it has. Although
this particular guideline is not directly associated with uterine rupture, it can have a great affect
on the health of your baby. Smaller hospitals tend to have limited options in the state of an
emergency. Patients at high or uncertain risk need to be under careful examination and have a
rapid response to any complications. These situations are more apparent within larger hospitals
(Guise, 2004). To prove this statement, there were 63 uterine ruptures in hospitals delivering <
3000 births per year and 20.6% resulted in perinatal death. However, there were 61 uterine
ruptures in hospitals delivering >3000 births per year and 6.6% resulted in perinatal death (Smith
et al., 2004). Resources include more staff within the hospital, more options readily available in
the state of emergency and a faster response time. “Hospitals with greater throughput are more
likely to have resident obstetric, anesthetic, and neonatal services as well as dedicated obstetric
theatre” (Smith et al., 2004).
Figure 2:
Mortality rates depending on size of hospital
% of Deaths/10000 deliveries
12
10
8
6
Series1
4
2
5
0
1-999
1000-1999
2000-2999
Deliveries per year in hospitals
3000-3999
<4000
Figure 2 shows the relationship between the number of deliveries per year in hospitals
(size of hospital) and infant mortalities. This occurs because of the lack of resources.
This visual information should help you to understand the impact of different hospital’s
resources. There is such a small window of opportunity when it comes to performing an
emergency cesarean delivery that a rapid response is needed. Every second is a matter of life or
death for mother or child. Although I have never experienced a pregnancy or birth, I have seen
women go through such emotion when it comes to emergencies regarding the birthing process.
These emotions can hinder the decision making process, so it is best for you and your family to
have the knowledge to make the decision to have a c-section after trying VBAC if there are
complications.
The size of the hospital is one of the most important factors contributing to the risk of
perinatal death due to uterine rupture because it can be prevented. The size of the hospital is a
straightforward aspect that could help or hinder the birthing process. You as a mother can do
research before entering the birthing process to figure out which hospital would be best for your
specific situation. Every mother and father expects the best care for the life that they are
bringing into this world. So make sure you choose a hospital that you feel will give you the best
options.
Guideline Two: Condition of Uterine Scar Tissue from Previous C-Section
“The rate of uterine rupture varies according to the type and location of cesarean
incision” (Sen et al., 2004). There are two different types of uterine scar: one is a classical
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uterine incision which extends into the uterine fundus and the other is a low transverse uterine
incision. The classical uterine incision is associated with a 12% risk of uterine rupture. The low
transverse uterine incision accounts for a risk of uterine rupture during trial of labor (TOL) in
less than 1% (O’Brien-Abel, 2003). Recent studies have shown that the risk of uterine rupture is
directly related to the thinning of lower uterine segment (Sen et al., 2004). The segment
thickness is said to be too thin at or below 2mm (Sen et al., 2004). There are two methods used
in measuring the thickness of the scar, and they are transabdominal ultrasonography with
magnification and transvaginal sonography. The measurements of the lower uterine segment are
taken when women are in the midst of labor between contractions with a pregnancy of duration
of 37 to 42 weeks (Sen et al., 2004).
Figure 3a:
Successful VBAC at each thickness
12
Number of patients
10
8
6
Transabdominal USG
4
2
0
<2
2.1-2.5
2.6-3.0
3.1-3.5
3.6-4.0
4.1-4.5
4.6-5.0
5.1-5.5
Thickness in mm
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Figure 3b:
Successful VBAC at each thickness
16
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Number of patients
12
10
8
Transvaginal ultrasonography
6
4
2
0
<2
2.1-2.5
2.6-3.0
3.1-3.5
3.6-4.0
4.1-4.5
4.6-5.0
5.1-5.5
Thickness in mm
Figures 3a & 3b demonstrate that with both methods of testing the thickness of the
uterine segment show that between 2.6 and 3.0 is the best thickness for a successful VBAC.
However the transvaginal ultrasonographic produces better results.
Ultrasonographic evaluation permits better assessment of the risk of scar complication
intrapartum, and could allow for safer management of delivery (Sen et al., 2004). This particular
guideline is important and easy to follow because it is a specific measurement. However, as with
hospitals you cannot find out your segment thickness until during labor. Because you know that
the thickness is too thin below 2mm, you and your doctor can make a fast decision. Another
strong aspect of this guideline is that you know what kind of incision you received during your
cesarean section, so you can know that according to research the low transverse uterine incision
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shows less risk to a rupture later on. Since ultrasonographic evaluation is better for assessment,
you know you will be getting the best care that research as offered.
Guideline Three: Inter-delivery Interval
Another condition that puts you, the mother, in danger is the inter-delivery interval. This
is simply the time between your previous cesarean section and your TOL. Research states that
shorter inter-delivery intervals have a higher risk of uterine rupture than those with intervals of
19 months or more (Huang, Nakashima, Rumney, Keegan, & Chan, 2002). This short time
between births can result in the incomplete healing of the uterine scar, which then can lead to
uterine rupture (Huang et al., 2002). Research states that women with < or equal 12 months of
gestation had a rate of 4.8% for uterine rupture and a 2.9% rate of uterine rupture with a
gestation between 13 to 24 months (Bujold, E., Mehta, Bujold, C., & Guathier, 2002). On the
other hand, the rate of uterine rupture in women with a gestation of >24 months was 0.9%
(Bujold, E. et al., 2002).
This guideline is also a very strong one because you can know from the moment you
conceive your child after having a previous cesarean section if the length of your gestation is
going to put you in higher risk for uterine rupture. You can know right away so you can make
arrangements accordingly.
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Guideline Four: Condition of Fetal Heart Rate
As with many problems that do happen in the delivery room, monitoring the fetal heart
rate (FHR) is a major factor in making decisions of the options of delivery. The distress of the
FHR is the most common signs of uterine rupture (Asakura, Oda, Tsunoda, Matsushima, Kaseki,
& Takeshita, 2004). FHR abnormality two hours prior to uterine rupture occurs in
approximately 80% of uterine rupture (Asakura et al., 2004). However the abnormality of the
FHR may depend on the site and size of the rupture and the elapsed time of the rupture (Asakura
et al., 2004). Prolonged deceleration of the FHR occurred in 55 out of the 78 women (71%),
where uterine rupture happened. Prolonged deceleration was defined as a FHR less than 90 beats
per minute that exceeded one minute without return to baseline (O’Brien-Abel, 2003). Again,
these numbers can give you an idea as to the signs of a distressed FHR. The most common fetal
heart rate abnormalities that occurred prior to uterine rupture were recurrent late decelerations
and bradycardia. Bradycardia is defined as the heart rate under 120 bpm (Ayers, Johnson, &
Hayashi, 2001). Late decelerations are caused by decreased uterine blood flow. The appearance
of recurrent late decelerations may be an early sign of impending uterine rupture. (Ayers et al.,
2001).
Since the FHR occurred in such a high percentage of uterine rupture, this a very serious
guideline. Usually when the FHR is distressed during labor, the doctor will decide to go into
emergency cesarean section to save the mother and child. From the research, it is pretty well
discussed that once the FHR reaches late decelerations and bradycardia, there is no time to
consider VBAC. So this guideline is more of a warning so you can know the dangers that could
happen if something is not done.
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Guideline Five: Induction of Labor with Prostaglandins
The last predisposing factor to uterine rupture is labor induction with prostaglandins
while undergoing VBAC-TOL. Prostaglandins are involved with the inductions of labor and
other reproductive processes and cause uterine contractions. One of the reasons this is
controversial is because when induced with prostaglandins, the intervals in which the doctor
checks up on the patient is between 4 and 6 hours (Guise, 2004). So within this time, something
can take a turn for the worse and put your life and your baby’s life in jeopardy. Among women
who had not previously given birth vaginally, the risk of uterine rupture without induction of
labor with prostaglandin was one in 210 and with induction of labor with prostaglandin was one
in 71(Smith, Pell, Pasupathy, & Dobbie, 2004).
Some reviews have compared induction with oxytocin with induction of prostaglandins.
Oxytocin has the same affect as prostaglandins with the stimulation of uterine smooth muscle
contraction. The intervals in which the doctors check on the patients with the induction of
oxytocin are between 15-45 minutes (Guise, 2004). With this method, there is less of chance of
something serious happening. However, there have not been studies performed in the actual
comparison of induction with prostaglandin to that of oxytocin. On the other hand, some studies
have reported that induction with any medications can lead to higher risks of uterine rupture.
This guideline is not fully researched as the previous four, but because it can still be a
cause of uterine rupture, I wanted to inform you of this one. This one is not as serious as the
other four, but is still a possibility.
Conclusions:
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After learning about all these factors that could potentially contribute to uterine rupture
while trying VBAC, you are in a more educated position to make the choice and do further
research for the health of yourself and your unborn baby.
One major question that can be asked throughout the scientific and general populations is
should VBAC even be considered as an option? If it is considered should the decision to try
VBAC be yours and your partners? As stated above, the decision is yours and your partners to
make, but because there is such limited research done, the awareness of uterine rupture is not
nearly where it should be, especially for women in your position.
On the other side of the spectrum, there are people and hospitals around the country that
feel it is their choice and not your choice to decide if VBACs are too risky. There are about 250
hospitals nationwide that will not even perform VBACs because they do not want to risk the
consequences (Anstett, 2004). The reason for this is because the physicians and the hospitals are
worried that they will be sued if the baby is born with problems. The decision to stop
performing VBACs at most hospitals was because they were unable to keep the required staff on
call for a VBAC in case an emergency occurred. Some other women in your position do not feel
this is the correct way to handle such a situation because if a hospital cannot handle VBACs than
they are certainly not safe for regular births.
I know for a fact that the hospital in the city where I was born will not allow the mother
to even attempt a VBAC. This is because the hospital does not want to risk innocent lives, when
they know for a fact that mortality can be prevented. Now more and more hospitals are banning
VBACs all together. They say there is too much risk in even beginning labor with VBAC and
would rather schedule a repeat cesarean section (Anstett, 2004).
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In result of hospitals banning VBACs, it is taking away the choice of you and your
partner. You and your partner should have the right to make this decision because it is your life
and your feelings. As stated above, the hospitals choosing to ban VBACs is because they cannot
have the staff on call. This should not be the hospitals choice because if the mother wants to do
this the hospital should accommodate her if they are able to. This is the reason why the 250
hospitals nationwide have a weak argument. The smaller hospitals have the right to choose, but
the larger hospitals do not if they do in fact of the required staff.
On the other hand, the aspect that limits my findings is that this is such a rare occurrence
and therefore there is not enough information. But by drawing these conclusions, I hope to
further research within this field. The population tested was different from study to study. This
also limits the guidelines. But we do know that these guidelines often lead up to uterine rupture
in the majority of the population tested.
I hope that I have accomplished my goal of giving you better knowledge about uterine
rupture if you are in a position of wanting to make an educated decision. My goal was to give
you instances in which a uterine rupture is possible. Mothers need to be educated in all areas of
pregnancy, delivery and when you take your child home. This article was meant to give you
confidence when you are in labor and before when you are discussing options with your
physician. I think it is important for women to have a voice when you or your baby’s life is at
stake.
So when researching the options of your birthing process, ask your hospital and doctor
questions that pertain to the resources. For example; what would they do in an instance of an
emergency c-section? Or what and how many factors would need to occur in order to perform a
c-section? Or what are the resources and do they have them in order to have a safe birth? Last
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but not least, will the hospital have enough staff to accommodate your needs if indeed an
emergency does happen?
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