Send to a Friend   Printer Friendly   Save in My Connection   

Best Evidence: C-Section



Best evidence: When making important maternity decisions, women should have information from the best available research about the safety and effectiveness of different choices. In general, we can be most confident about results of systematic reviews that summarize randomized controlled trials (or RCTs, a type of study).

Unfortunately, for many decisions we must rely on less definitive research; and many important questions — even in the case of widely used drugs, tests and procedures — have hardly been studied at all. Although this situation is discouraging, an awareness of weak or missing evidence can help you make informed choices about care.

A systematic review comparing the full range of risks to help you make a truly informed decision.

What is the bottom line?

What are some concerns about physical effects of cesareans on mothers around the time of birth?

What are some concerns about psychological effects of cesareans on mothers around the time of birth?

What are some concerns about ongoing effects of cesareans on mothers?

What are some concerns about effects of cesareans on babies?

What are some concerns about effects of cesareans on mothers in future pregnancies and births?

What are some concerns about effects of cesareans on future babies (when a baby grows in a uterus with a cesarean scar)?

What is a concern about effects of vaginal birth on mothers?

What is a concern about effects of vaginal birth on babies?



A systematic review comparing the full range of risks to help you make a truly informed decision

Childbirth Connection carried out a systematic review of research to help you make informed decisions about cesarean versus vaginal birth. While more high-quality studies are needed, a large body of studies already exists and sheds light on these questions for those who need guidance now. This section summarizes results of the most relevant and better quality studies among hundreds that were examined (see review reference at end of this page).

Since the decision about whether to have a vaginal birth or a cesarean section can impact you and your baby in many ways, it is essential that you understand expected benefits along with the full range of possible risks to you and your baby.

The information here covers a broad range of outcomes — physical as well as emotional effects in mothers and babies, and shorter- and longer-term risks (including any future pregnancies).

Even if you do not plan to have more children, you should be aware of risks for future pregnancies. Many women change their mind about becoming pregnant again or decide to carry through with an unplanned pregnancy.

What is the bottom line?

The conclusions in this section were reached after reviewing the best studies that were found comparing different ways of giving birth. They are collected below into two lists:

  • 33 areas where cesarean section was found to involve more risk than vaginal birth, and
  • 4 areas where vaginal birth was found to involve more risk than cesarean section.
If you consider a cesarean, it is important to weigh any benefits the surgery is expected to offer against the risks involved. The benefits depend on your specific situation and the reason why your doctor or midwife may be recommending a cesarean. It is important to discuss these issues with your caregiver.

KEY MESSAGES ABOUT CESAREAN SECTION COMPARED WITH VAGINAL BIRTH See details about these effects after the following summary lists.

Extra risks associated with cesarean section: Current research suggests that cesarean section has the following disadvantages in comparison with vaginal birth:

  • Physical problems in mothers: Compared with vaginal birth, cesarean section increases a woman's risk for a number of physical problems. These range from less common but potentially life-threatening problems, including hemorrhage (severe bleeding), blood clots, and bowel obstruction, to much more common concerns such as longer-lasting and more severe pain and infection. Even after recovery from surgery, scarring and adhesion tissue increase risk for ongoing pelvic pain and for twisted bowel.
  • Hospitalization of mothers: If a woman has a cesarean, she is more likely to stay in the hospital longer and is at greater risk of being re-hospitalized.
  • Emotional well-being of mothers: A woman who has a cesarean section may be at greater risk for poorer overall mental health and some emotional problems. She is also more likely to rate her birth experience poorer than a woman who has had a vaginal birth.
  • Early contact with, feelings toward babies: A woman who has a cesarean usually has less early contact with her baby and is more likely to have initial negative feelings about her baby.
  • Breastfeeding: Recovery from surgery poses challenges for getting breastfeeding under way, and a baby who was born by cesarean is less likely to be breastfed and get the benefits of breastfeeding.
  • Health of babies: Babies born by cesarean are more likely to:
    • be cut during the surgery (usually minor)
    • have breathing difficulties around the time of birth
    • experience asthma in childhood and in adulthood.
  • Future reproductive problems for mothers: A cesarean section in this pregnancy puts a woman at risk for future reproductive problems in comparison with a woman who has a vaginal birth. These problems may involve serious complications and medical emergencies. The likelihood of experiencing some of these conditions goes up sharply as the number of previous cesareans increases. These problems include:
    • ectopic pregnancy: pregnancies that develop outside her uterus or within the scar
    • reduced fertility, due to either less ability to become pregnant again or less desire to do so
    • placenta previa: the placenta attaches near or over the opening to her cervix
    • placenta accreta: the placenta grows through the lining of the uterus and into or through the muscle of the uterus
    • placental abruption: the placenta detaches from the uterus before the baby is born
    • rupture of the uterus: the uterine scar gives way during pregnancy or labor.
  • Concerns about babies in future pregnancies: A cesarean section in this pregnancy can affect the babies of future pregnancies. Studies have found that they are more likely to:
    • be born too early (preterm)
    • weigh less than they should (low birthweight)
    • have a physical abnormality or injury to their brain or spinal cord
    • die before or shortly after the birth
  • Planned cesarean compared with unplanned cesarean: A planned cesarean offers some advantages over an unplanned cesarean (a cesarean that occurs after labor is under way). For example, there may be fewer surgical injuries and fewer infections. The emotional impact of a cesarean that is planned in advance appears to be similar to or somewhat worse than a vaginal birth. By contrast, unplanned cesareans can take a greater emotional toll.
  • Planned cesarean compared with vaginal birth: A planned cesarean still involves the risks associated with major surgery. And both planned and unplanned cesareans result in a uterine scar and internal scarring and adhesions. This means women with planned and unplanned cesareans face similar risks in future pregnancies and for problems related to scarring and adhesions at any time
Extra risks associated with vaginal birth: In a few areas, mothers or babies with vaginal birth have poorer outcomes in comparison with cesarean birth.

  • Perineal pain: While a woman with a cesarean birth is more likely to experience more intense and longer-lasting pain overall, a woman with a vaginal birth is more likely to experience pain in the vaginal area in the weeks and months after birth.
  • Incontinence: A woman with a vaginal birth is more likely to leak urine (urinary incontinence) and to leak gas or, more rarely, feces (bowel incontinence). Pregnancy itself and other factors such as the woman's weight play a role in these problems. Few women experience troubling symptoms beyond the recovery period in the weeks and months after birth.
  • Nerve injury in babies: In comparison with a baby born by cesarean section, a baby who is born vaginally is more likely to have a nerve injury that affects the shoulder, arm or hand.

Relationship between care during birth and pelvic floor problems: More and more research finds that some practices used at the time of pushing increase the likelihood of pelvic floor injury. Many women experience one or more of these during vaginal birth. You can lower your risk by choosing a caregiver and birth setting with low rates of intervention. These practices include:
  • cutting an episiotomy
  • using vacuum extraction or forceps to help bring the baby out
  • having women give birth while lying on their backs
  • using caregiver-directed pushing, which is often more forceful than having the woman and her own reflexes guide pushing
  • pressing on the woman's abdomen to help move the baby out
Of hundreds of studies examined to compare vaginal and cesarean birth, not one attempted to avoid or limit the use of practices that can injure a woman's pelvic floor to try to determine whether vaginal birth itself contributes to pelvic floor problems. It is wrong to conclude at this time that the cause of pelvic floor problems is giving birth through the vagina.

Pelvic Floor Dysfunction is a full Pregnancy Topic on this important issue.



MORE DETAILED INFORMATION ABOUT RISKS NOTED ABOVE

Click below on VERY HIGH, HIGH, etc. to understand difference in level of risk between care options.

On the rest of this page, you will find details about:


What are some concerns about physical effects of cesareans on mothers around the time of birth?

Having a cesarean section rather than a vaginal birth increases risk for the following problems:

  • maternal death: some studies found that cesarean surgery itself, not any problems that led to surgery, appeared to cause additional maternal deaths compared with vaginal birth.
    Added likelihood for a woman with a cesarean: LOW to VERY LOW for maternal death
  • emergency hysterectomy: a woman with a cesarean is more likely than a woman with vaginal birth to have emergency surgery to remove her uterus (hysterectomy) in the early weeks after birth.
    Added likelihood for a woman with a cesarean: MODERATE for emergency hysterectomy
  • blood clots and stroke: a woman with a cesarean appears to be more likely than a woman with vaginal birth to have blood clots, including clots blocking blood vessels in the lungs (pulmonary embolism) and blocking blood flow to the brain (stroke).
    Added likelihood for a woman with a cesarean: LOW for blood clots and stroke
  • injuries from surgery: all women who have a cesarean have a wound; a woman with a cesarean may also be injured from accidental cuts to nearby organs such as the bladder or bowel or ureter (the tube that carries urine from the kidney to the bladder), especially if the surgery is done in haste.
    Added likelihood for a woman with a cesarean: VERY HIGH for abdominal wound
    Added likelihood of accidental cuts from surgery cannot be determined from studies examined
  • longer time in hospital: a woman who has a cesarean usually stays in the hospital a day or two longer than a woman who has a vaginal birth for post-operative monitoring and care, and this stay may be extended if she has complications.
    Added likelihood for a woman with a cesarean: VERY HIGH for a longer time in the hospital
  • going back into the hospital: a woman who has a cesarean is more likely than a woman with vaginal birth to be readmitted to the hospital in the weeks after birth.
    Added likelihood for a woman with a cesarean: MODERATE for going back to the hospital
  • infection: a woman with a cesarean is at risk for wound infection and may be much more likely than a woman with vaginal birth to have an infected uterus; women with a cesarean generally receive routine antibiotics to try to prevent infection.
    Added likelihood for a woman with a cesarean: HIGH for infection
  • pain: in the first days and weeks after birth, a woman who has had a cesarean is likely to have more intense and longer-lasting pain than a woman with vaginal birth; most women with a cesarean use pain medication after birth and consider pain at the cesarean wound to be a problem.
    Added likelihood for a woman with a cesarean: VERY HIGH for more severe and longer-lasting pain

What are some concerns about psychological effects of cesareans on mothers around the time of birth?

Having a cesarean section rather than a vaginal birth increases risk for the following problems:

  • poor birth experience: a woman with a cesarean tends to give lower ratings to her birth experience than a woman with a vaginal birth, both early on and over time; she may be less likely to have her partner or other support people present; and to feel that she had control.
    Added likelihood for a woman with a cesarean: VERY HIGH to HIGH for poor birth experience (unplanned cesarean is worse than planned cesarean, vaginal birth with vacuum extraction or forceps is worse than vaginal birth without these procedures)
  • less early contact with her baby: a woman with a cesarean is less likely to see and hold her baby soon after birth than a woman with vaginal birth.
    Added likelihood for a woman with a cesarean: VERY HIGH for seeing and holding the baby later
  • unfavorable early reaction to her baby: early on, a woman with a cesarean is more likely to have negative feelings about her baby and to evaluate her baby less favorably than a woman with vaginal birth.
    Added likelihood for unfavorable early reaction to babies cannot be determined from studies examined
  • depression: a woman who has had a cesarean may be at higher risk for depression than a woman with vaginal birth.
    Current evidence is mixed on whether cesarean increases likelihood of depression
  • psychological trauma: a woman who has an unplanned cesarean during labor is at higher risk than other mothers for having traumatic symptoms (such as fear and anxiety) and for meeting criteria of Post-Traumatic Stress Disorder (PTSD).
    Added likelihood for a woman with an unplanned cesarean: HIGHfor having traumatic symptoms and for meeting criteria of PTSD (unplanned cesarean or vaginal birth with vacuum extraction or forceps pose HIGH extra risk in comparison with planned cesarean or vaginal birth with no vacuum/forceps)
  • poor overall mental health and self-esteem: a woman who has a cesarean section may be at greater risk for poorer overall mental health and lower self-esteem than a woman with vaginal birth.
    Added likelihood for poor overall mental health and self-esteem cannot be determined from studies examined
  • poor overall functioning: a woman who has a cesarean section may face greater challenges than a woman with vaginal birth for physical and social functioning and carrying out daily activities in the early weeks after birth.
    Added likelihood for poor overall functioning cannot be determined from studies examined

What are some concerns about ongoing effects of cesareans on mothers?

Having a cesarean section rather than a vaginal birth increases risk for the following problems:

  • ongoing pelvic pain: a woman who has had a cesarean may have ongoing pelvic pain, possibly due to scarring and the growth of adhesion tissue.
    Added likelihood for ongoing pelvic pain cannot be determined from studies examined
  • bowel obstruction: a woman who has had a cesarean may develop twisted and blocked intestines in the years after surgery as a result of scarring and adhesion tissue in the abdomen.
    Added likelihood for a woman with a cesarean: MODERATE for bowel obstruction

What are some concerns about effects of cesareans on babies?

When mothers experience physical or emotional problems as a result of a cesarean birth (see above), it may interfere with their ability to take care of their babies. In addition, having a cesarean section rather than a vaginal birth increases risk for the following problems in babies:

  • surgical cuts: a baby born by cesarean section may be accidentally cut (usually minor) during the surgery.
    Added likelihood for a baby born by cesarean: HIGH for accidental surgical cuts
  • respiratory problems: a baby born by a planned cesarean before the 39th week of pregnancy is at higher risk for mild to serious lung and breathing problems than other babies born at the same time.
    Added likelihood for a baby born by cesarean: HIGH to MODERATE for respiratory problems with a planned cesarean before 39 weeks
  • not breastfeeding: a mother who has had a cesarean faces extra challenges in getting breastfeeding under way, and her baby is less likely to be breastfed than a baby born vaginally.
    Added likelihood for a baby born by cesarean: VERY HIGH to HIGH for not breastfeeding
  • asthma: a person who is born by cesarean section appears to be at higher risk than a person born vaginally for asthma, both in childhood and in adulthood.
    Added likelihood for a person born by cesarean: HIGH for greater risk for asthma

What are some concerns about effects of cesareans on mothers in future pregnancies and births?

All pregnant women should be aware of these risks. Many women who do not expect to have more children change their mind or decide to continue with an unplanned pregnancy.

In future pregnancies, the placenta, embryo and fetus that grow in a uterus with a cesarean scar may not function as well as those that develop in an unscarred uterus. The likelihood of the following problems may increase as the number of previous cesareans increases. Having a cesarean section rather than a vaginal birth increases risk for the following problems for in future childbearing:

  • infertility: a woman who has had a cesarean is more likely than a woman with a previous vaginal birth to have difficulty conceiving another baby and is less likely to ever have another baby.
    Added likelihood for a woman with a previous cesarean: VERY HIGH to HIGH for infertility (not by choice)
  • reduced fertility: a woman who has had a cesarean is more likely than a woman with a previous vaginal birth to have negative feelings and attitudes about childbirth, to decide not to have additional children, and to point to these feelings and attitudes as the reason for this decision.
    Added likelihood for a woman with a previous cesarean: HIGH for reduced fertility by choice
  • maternal death: in future pregnancies and births, a woman whose uterus has a cesarean scar is more likely than a woman with a previous vaginal birth to have life-threatening problems with the placenta and the scar (see next points).
    Added likelihood for a woman with a previous cesarean: has not been measured well, may be VERY LOW for maternal death related to scar
  • ectopic pregnancy: a woman whose uterus has a cesarean scar is more likely than a woman with an unscarred uterus to have an embryo grow outside her uterus, including a cesarean scar pregnancy; in such cases, the pregnancy must be ended to save her life, and she may have severe bleeding, emergency surgery, which may include emergency removal of her uterus (hysterectomy), and other complications.
    Added likelihood for a woman with a previous cesarean: MODERATE for ectopic pregnancy
  • placenta previa: a woman whose uterus has a cesarean scar is more likely than a woman with an unscarred uterus to have a future placenta attach near or over the opening to her cervix; this increases her risk for serious bleeding, shock, blood transfusion, blood clots, planned or emergency delivery, emergency removal of her uterus (hysterectomy), placenta accreta (see next), and other complications.
    Added likelihood for a woman with a previous cesarean: MODERATE for placenta previa in a future pregnancy after having one cesarean; HIGH for placenta previa in a future pregnancy after having more than one cesarean
  • placenta accreta: a woman whose uterus has a cesarean scar is more likely than a woman with an unscarred uterus to have a future placenta grow through the uterine lining and into or through the muscle of the uterus; this increases her risk for a ruptured uterus (see below), serious bleeding, shock, blood transfusion, emergency surgery, emergency removal of her uterus (hysterectomy), and other complications.
    Added likelihood for a woman with at least one previous cesarean: MODERATE for placenta accreta in a future pregnancy
  • placental abruption: a woman whose uterus has a cesarean scar is more likely than a woman with an unscarred uterus to have a future placenta detach from her uterus before the baby is born; this increases her risk for severe bleeding, shock, blood transfusion, blood clots, planned or emergency cesarean delivery, and other complications, and it may reduce oxygen and nutrients to her baby
    Added likelihood for a woman with a previous cesarean: MODERATE for placental abruption
  • rupture of the uterus: a woman whose uterus has a cesarean scar is more likely than a woman with an unscarred uterus to have the wall of the uterus give way in a future pregnancy or labor, especially at the site of the scar; this increases her risk for severe bleeding, shock, blood transfusion, blood clots, planned or emergency cesarean delivery, emergency removal of the uterus (hysterectomy), and other complications; whether a woman plans a repeat cesarean or a VBAC (vaginal birth after cesarean), she is at greater risk for a ruptured uterus than a woman with no previous cesarean.
    Added likelihood for a woman with a previous cesarean: MODERATE for rupture of the uterus

What are some concerns about effects of cesareans on future babies (when a baby grows in a uterus with a cesarean scar)?

A placenta that grows in a uterus with one or more scars from a previous cesarean section may not do as well at providing oxygen and nutrients to the developing fetus compared with a placenta growing in an unscarred uterus. This may cause life-threatening problems. The likelihood of the following problems may increase as the number of previous cesareans increases.

In comparison with a baby that develops in a uterus with no cesarean scar, a baby that develops in a uterus with a cesarean scar is at increased risk for the following problems:

  • death: a baby who develops in a uterus with a cesarean scar appears to have an increased risk of dying before (stillbirth) or shortly after birth compared with a baby who develops in an unscarred uterus.
    Added likelihood for a baby who grows in a uterus with a cesarean scar: MODERATE for death of the baby
  • low birthweight and preterm birth: a baby who develops in a uterus with a cesarean scar may be at higher risk for being born too small (low birthweight) and for being born too soon (preterm birth) than a baby who develops in an unscarred uterus.
    Added likelihood for low birthweight and preterm birth cannot be determined from studies examined
  • malformation: a baby who develops in a uterus with a cesarean scar may be at higher risk for having a physical malformation that develops before birth than a baby who develops in an unscarred uterus.
    Added likelihood for malformation cannot be determined from studies examined
  • central nervous system injury: a baby who develops in a uterus with a cesarean scar may be at higher risk for having a brain or spinal cord injury than a baby who develops in an unscarred uterus.
    Added likelihood for central nervous system injury cannot be determined from studies examined

What is a concern about effects of vaginal birth on mothers?

Having a vaginal birth rather than a cesarean section increases risk for the following problems:

  • painful vaginal area: a woman who has a vaginal birth is more likely than a woman who has a cesarean to have a painful vaginal area in the weeks and months after birth.
    Added likelihood for a woman with vaginal birth: VERY HIGH for a painful perineum in the weeks and months after birth
  • urinary incontinence: a woman who has a vaginal birth is more likely than a woman who has a cesarean to leak urine.
    Added likelihood for a woman with vaginal birth: depends on how this is defined, time elapsed since the birth, and procedures and practices used during vaginal birth. (How can I prevent pelvic floor problems when giving birth? is a full Maternity Topic on this website.)
  • bowel incontinence: a woman who has a vaginal birth is more likely than a woman who has a cesarean to have leakage of gas or, more rarely, of feces.
    Added likelihood for a woman with vaginal birth: depends on how this is defined, time elapsed since the birth, and procedures and practices used during vaginal birth. (How can I prevent pelvic floor problems when giving birth? is a full Maternity Topic on this website.)

What is a concern about effects of vaginal birth on babies?

Vaginal birth poses the following risk for babies:

  • birth injury: in comparison with cesarean birth, a baby born by vaginal birth may be at higher risk for nerve injury affecting the shoulder, arm or hand (brachial plexus injury); although most of these injuries are temporary, some are permanent. Added likelihood for a baby born with vaginal birth: LOW for brachial plexus injury.

Reference

Childbirth Connection. Comparing risks of cesarean and vaginal birth to mothers, babies, and future reproductive capacity: a systematic review. New York: Childbirth Connection, April 2004. [The following study documents are available as PDF files from the Childbirth Connection website: description of methods and sources (including full bibiliography), list of main questions and outcomes (a table of contents for evidence tables), first file of evidence tables, and second file of evidence tables.]

Most recent page update: 9/3/2009


© 2010 Childbirth Connection. All rights reserved.

Childbirth Connection is a national not-for-profit organization founded in 1918 as Maternity Center Association. Our mission is to improve the quality of maternity care through research, education, advocacy and policy. Childbirth Connection promotes safe, effective and satisfying evidence-based maternity care and is a voice for the needs and interests of childbearing families.
News and Features

"2020 Vision" and "Blueprint for Action" Reports Available
Leaders from across the U.S. health care system have prepared several reports for improving the maternity care system.
Learn about Transforming Maternity Care project
Read the "2020 Vision"
Read the "Blueprint for Action"
Read the Consumer Workgroup report
Help implement Blueprint recommendations

Rising Maternal Mortality
Analysis of maternal mortality data for the state of California, with 14% of the nation's births, strongly suggests that maternal mortality is increasing in tandem with rising rates of cesarean section and obesity.
Read article about maternal mortality in California 
Read companion Q&A 

Maternity Care Fact Sheet Available
A new fact sheet (12/09) summarizes U.S. maternity care trends and figures from the latest federal reports. The fact sheet updates background information in the 2008 Milbank Report on Evidence-Based Maternity Care.
Get the fact sheet 
Read Evidence-Based Maternity Care 

US Cochrane Center (USCC)/Consumers United for Evidence-based Healthcare (CUE)
Visit the USCC/CUE website for the latest pregnancy and childbirth systematic reviews.

Maternity Care, a Major Segment of Health Industry, Must Be Overhauled for Health Care Reform to Succeed
As competing interests work out the particulars of health care reform, Childbirth Connection reminds the nation that rapid gains in the quality, cost, and value of maternity care are achievable.
Read the press release (PDF)

National Policy Symposium Honors Childbirth Connection's 90th Anniversary

Nearly 250 leaders deliberated about Transforming Maternity Care in Washington DC in April 2009.
Learn about symposium, next steps
See 90 years of milestones for women and families (PDF)

Seton Family of Hospitals Receives First Maternity Quality Matters Award
Childbirth Connection presented its inaugural Maternity Quality Matters Award to an organization that is achieving significant gains for women and newborns.
Learn more about award winner

Maternity Care Priorities in Health Care Reform

Childbirth Connection has issued a statement about health care reform priorities for a high quality, high value maternity care system.
Read the statement (PDF) 

Evidence-Based Maternity Care Report Released
A major new report takes stock of the U.S. maternity care system and finds great opportunities for improvement. Childbirth Connection collaborated with the Reforming States Group and the Milbank Memorial Fund to develop the report.
Learn more, get the report 
Read companion USA Today article
Read the USA Today article
Read the Consumer Reports story
Take the Consumer Reports quiz
Read Our Bodies Our Blog entry

eNews Sign Up
Occasional news on maternity care research and other useful info.
*

Our Privacy Policy
 Find us on Facebook logo  Tweet with us on Twitter
@childbirth

Help Transform Maternity Care!
Help Transform Maternity Care! Please join our efforts to make quality maternity care a top national priority. Your support will help make the transformation possible.
View 2009 Supporter Roster 

New Mothers Speak Out
National Report Released

The latest report in Childbirth Connection's Listening to Mothers series is now available. Get an eye-opening look at the reality of life as a mother of young children in the United States, based on national surveys conducted by Harris Interactive.
Learn more, get the report
Read the Wall Street Journal story and listen to the podcast
Download Quick Facts (PDF)
New Content!
journey to parenthood
Journey to Parenthood
Full Book Available Online!

A family-friendly book covering the trimesters, pregnancy resources, and the latest information on baby's first year of development. Available online (free) and for purchase in the Bookstore.
Browse through Journey to Parenthood childbirth connection journey to parenthood
Buy this book and learn more journey to parenthood in bookstore
"I love being a mother. My children add to so many aspects of my life"
-Listening to Mothers® survey participant
Every woman has the right to full and clear information about benefits, risks, and costs of the procedures, drugs, tests and treatments offered to her, and of all other reasonable options, including no intervention. She should receive this information about all interventions that are likely to be offered during labor and birth well before the onset of labor.