Would You Rather...

DISCLAIMER: there are graphic pictures in this post.

This is the post that makes women squirm, clamp their knees together, and raise their blood pressure in angst. We are going to talk about tears and episiotomies. I know, I know - it makes my stomach flip and my PC clench.

I think the most 'catch 22' question of pregnancy is the infamous, 'would you rather tear or have an episiotomy?'. Now, any woman in her right mind would say NEITHER! And wisely so.

Don't worry, we are going to talk about how to minimize the risk of tearing altogether. But, in the spirit of informed decision making, we will be talking about what both tears and episiotomies are, the risks and benefits of each, and how to minimize the risk of either occurring. 

TEARS
Let's start with tears. Tears occur for a number of reasons. Some of these include:

• The position mom is pushing in
• If baby has a nuchal hand or arm
• The speed at which crowning occurs
• How aggressive or hands-on the care provider is
• If instrumental delivery is being employed
• How relaxed and elastic mom's perineum is
• How toned and sinewy mom's pubococcygeous muscle is 
• Mom's Ethnicity 

Tearing is a natural separation of the tissue at the outlet of the vaginal opening, usually through the perineal tissue toward the anus. Some times, it occurs anteriorly, or toward the urethra/clitoris. Most tears that occur spontaneously occur at crowning and are less than 1st degree and up to 2nd degree lacerations. Although 3rd and 4th degree tears do occur naturally, it does not occur very often.

Vaginal lacerations, both naturally occurring (tears) and surgically performed (episiotomies) are measured in degrees. The degrees of lacerations are explained below:

• Skid Marks -The most common naturally occurring laceration. These are usually less deep than a split lip and do not require any stitches. They heal within a matter of days after birth.
• First Degree (1st) - The smallest laceration, extending only through the vaginal mucosa. It does not involve the underlying tissues. Many midwives do not recommend even stitching these as they heal easily when naturally occurring.
• Second Degree (2nd) - The most common type of episiotomy. It extends through the vaginal mucosa and into the submucosal tissues.
• Third Degree (3rd) - this involves the vaginal mucosa, submucosal tissues, and some or all of the anal sphincter muscle.
• Fourth Degree (4th) - The most severe laceration. This includes the vaginal mucosa, submucosal tissues, anal sphincter muscle, and the lining of the rectum. This can lead to recto-vaginal fistula and a high rate of incontinence.

EPISIOTOMIES
The episiotomy, on the other hand, is performed for a different set of reasons.

• to prevent tearing
• suspected large baby
• suspected shoulder dystocia
• longer 2nd stage
• precipitous birth
• to prevent later incontinence
• fetal distress
• routine (doctor always does it)

Reports state that the US has anywhere from a 9% to over a 40% episiotomy rate.

Stephanie Soderblom LM CPM: www.azhomebirth.com

Simply put, an episiotomy is when a care provider cuts the vaginal opening down through the nerve-filled perineal tissue toward the anus with a pair of surgical scissors. Yep, scissors. For added benefit, though, I have included the more professional definition:

Episiotomy - an incision created in the vaginal opening and tissue surrounding it in order to enlarge the opening. From the root Episio, meaning vulva and tomy, meaning incision or sectioning.

Episiotomies are an automatic 2nd degree laceration, or more. There are two main types of episiotomies: the midline and the medio-lateral. The most common in the US is midline, while the medio-lateral episiotomy is more common in other parts of the world.

Types

A midline episiotomy is when the care provider incises the vaginal opening straight down toward the anus. This type of episiotomy is reported to have less pain and less incidence of long-term tenderness or pain during intercourse than the medio-lateral episiotomy. There is often less blood loss with a midline episiotomy as well. The biggest disadvantage of this episitiomy over the mediolateral is that this type of incision is very likely to continue tearing beyond the incision, causing a larger laceration.

A medio-lateral episiotomy begins at the vaginal opening and is cut at a 45-degree angle toward either the right or left buttocks. The main advantage of the medio-lateral episiotomy is that is has less chance of tearing beyond the incision. The risks include there is a significant increase in blood loss, increased pain, more difficult repair than a midline episiotomy, and the increased risk of long-term discomfort, especially during intercourse.
How Is an Episiotomy Performed?

How It's Performed
Ideally, an episiotomy would be done when 3-4cm of the baby's head is visible at the vaginal opening, and during a contraction. Although it is rather routine to inject a local anesthetic in the perineum when an episiotomy is anticipated, this injection actually makes the perineum LESS pliant, more likely to tear in the first place, and more likely to tear if beyond the incision if the episiotomy is performed. Instead, waiting until the woman is having a contraction and until the babies head is well applied to the perineum ensures that the woman's perineum will be numb from lack of blood flow to the perineum and minimize/eradicate discomfort during the incision.

The doctor or midwife would then insert two fingers into the vaginal opening to protect the baby's head and the incision, between 2-3cm in length, is made.

RISKS (aka WEIGHING THE OPTIONS)

• Risks of episiotomies over naturally occurring tears include:
• higher risk of muscle damage
• can cause tearing beyond the episiotomy (some reports cite 30% tear beyond the incision)
• can lead to urinary incontinence
• local anesthetics can cause more tearing by swelling tissues
• take longer to heal than a naturally occurring tear
• episiotomies always requires stitching
• women report more pain from episiotomies than from tearing
• episiotomies cause more extensive scar tissue than tearing
• higher rates of infection
• swelling
• higher rates of defects in wound closure
• higher rates of sexual dysfunction
• higher rates of recto-vaginal fistula
• higher rates of fecal incontinence

Women who do tear only tear as far as their body needs to to allow baby to pass by. Episiotomies are an automatic 2nd degree laceration, whether or not her body needs that space. And, many times, a woman will tear beyond the episiotomy that is performed.

I liken it to the phone-book tear test. Try tearing a phone book down the side, it is very difficult. Now, make an incision on that side. Now, try to tear it along that incision... the book is much easier to tear. This concept extends (no pun intended) to episiotomies and tearing beyond them.

 

In addition, tears heal faster, with less pain, and less scar tissue. This is because tissue cells look like little bricks. When a woman's perineum does tear, it tears through the 'cement' holding those bricks (cells) together - there is little to no cellular damage.

On the other hand, episiotomies are an unnatural laceration that tear right through healthy cells and the 'cement' around them, resulting in not only tissue damage, but also cellular damage. This increases infection rates, healing time, discomfort in healing, scar tissue, and long term pain and sexual dysfunction.

A final risk is this: there is absolutely no way for a provider to know beyond a shadow of a doubt that a woman will tear until she does. This means that episiotomies for 'might tear's sake is moot. Most episiotomies are unnecessary.

CONSIDERATIONS (aka WTH)

Let's deconstruct both the natural reasons a woman tears and the medical reasons a provider might cut.  

First, the natural reasons a woman might tear:

The position mom is pushing in - lithotomy/supine and semi-sitting (classic) positions have the highest incidence of tearing. Other positions that require mom to bring her legs back as far as possible toward her ears also have higher incidences of tearing. It is no surprise, then that women who have homebirths and birth center births have less incidences of tearing - they are able to choose whatever position feels best (which is usually not these positions) to push in and follow their bodies cues.

Many midwives who serve the Amish and Mennonite community also report that they have a nearly non-existent tearing rate. These communities often birth on their sides or in a squat with their knees together and their buttocks pressed backward. This makes physiological sense, as it decreases the pressure/tension on the perineal tissues, allowing more stretching to occur.

A woman's best bet is to get in a better position for birthing than lithotomy or supine.

Nuchal hands or arms - nuchal hands or arms mean that there is a hand or arm up near the neck/head. This means that there is something in addition to the babies head to fill that space, increasing the chance of tearing. Obviously, one cannot anticipate or correct this, but they can minimize the chances of tearing from occurring by allowing a slow and steady crowning and resolution to occur. They can also request perineal support and counterpressure to slow the process further. 

The speed at which crowning/shoulder birth occurs - the more time the perineum has to stretch, the less chance of tearing will occur. Likewise, the more precipitous the birth, the higher the chance of tearing. This risk increases, again, with coached pushing or purple pushing.

As a baby begins to crown, the skin stretches. This stretching can sometimes feel like tingling or burning, which is natures way of having mom slow down the pushing. Instinctually, women will let up on pushing and make some noise, blow air out, or 'horse-lip' for awhile, until the burning goes away.

The slower the stretching is allowed to occur, the less chance that tearing will occur. A woman can simply 'blow' through crowning, or even do 'horse lips' to allow her body to birth the baby's head and shoulders, slowing the process down and allowing for optimal stretching.

Another tip is to request gentle counterpressure or warm compresses on the perineum, to support the perineum during crowning and minimize the chances tearing.


Ways to minimize these risks are to request no coached pushing, employing blowing/horse lips through crowning or simply letting your body do the pushing, and warm compresses or counterpressure on the perineum.

How aggressive or hands-on the care provider is - the more the provider pulls on vaginal tissue during crowning, the more swollen the tissue will become, and less elastic. Also, the more the provider pulls on and manipulates baby's head, the greater the chance of tearing.

Likewise, it is common practice in the US to pull on baby's head after it is out to hasten the birth of the shoulders. This can create unnecessary tension on the perineum, causing iatrogenic tearing.

The best odds for a woman to eradicate this as a reason for her body to tear is to make sure she has a provider that she trusts to not to act aggressively with her perineum or her baby's body.

If instrumental delivery is being employed - if a vacuum extractor or forceps are used, the incidence of tearing does increase but is not guaranteed to occur. Because instrumental delivery means a more precipitous birth will most likely occur, as well as because there is the addition of a foreign object filling the vaginal opening along with the baby's head, the chances of tearing do increase, but again, is not a guarantee.

One way to minimize this possibility is, first and foremost, reduce your chances of needing instrumental assistance by considering an unmedicated birth, an upright position for birthing in, and patience to bring baby down, especially for first time babies, which, on average, take 2 hours of pushing. Another way to minimize the chance of tearing, if, after employing the above, you still require instrumental assistance, request gentle traction, when crowning begins, 'blow' through the contractions or don't push, and allow the shoulders to be born without the assistance of a vacuum or forceps.
 
How relaxed and elastic mom's perineum is - the more relaxed mom is, the more hydrated and well nourished mom is, the stretchier her perineum is.

When a mom can breath easily, without tensing up her pelvic floor, her perineum is able to stretch gently and optimally. Coached pushing should be avoided, and a mom should listen to her body's cues on when and how to push. Studies show that a woman's vocal folds/jaw/throat is directly related to how relaxed her bottom is.

In addition, good hydration and nutrition are vital for tissue health and elasticity. Drinking water during pregnancy and throughout labor and birth will ensure that your tissues are nice and supple and well hydrated. Likewise,

"Good nutrition is vital to your body's work in preparing the perineum for stretching during birth. Hormonal changes during pregnancy cause the tissues of your cervix and perineum to become extremely thick and elastic. Crucial to this process is an adequate intake of protein, vitamin E, and short-chain fatty acids, which consist of two types of 'good' fat, Omega-3 and Omega-6. Short-chain fatty acids are found in nuts and seeds, cold-pressed oils, all types of beans, and fish such as salmon and tuna" "Avoiding an Episiotomy", Nancy Griffin, Mothering Magazine, # 75, summer 1995, (p 60).

Vitamin C is also very beneficial for cellular elasticity and regeneration. It can be found in citrus foods, most readily, but also in dark green vegetables.

Finally, squats and intercourse encourage good circulation and elasticity of the perineal tissues. Squatting is natures way of keeping our bottoms healthy and sex encourages relaxed perineal tissue with good tone.


So, a mom can help ensure that her perineum is well prepped for birth through relaxation/vocalization/breathing, prenatal nutrition, prenatal and labor hydration, and prenatal exercise.

How toned and sinewy mom's pubococcygeous muscle is - how healthy a lifestyle mom lives and how well she has treated her PC muscle (sex, squats and Kegels) has great bearing on her ability to have a more controlled pushing stage, a well flexed baby's head, and less chance of tearing.

Women who have sex throughout pregnancy have well oxygenated, more toned and conditioned PC muscles, as well as have good control of this muscle. A toned and controllable PC muscle means that babies head is more likely to be well flexed, allowing the smallest part of the baby's head to emerge from the vaginal opening first, gently stretching mom's perineum for less chances of tearing.

In addition, squats will ensure that the PC muscle remains a long, sinewy muscle, keeping it elastic and not bulky and rigid. A woman should, during pregnancy, make sure that she is taking care of her PC muscle, making sure it is not only toned, but also stretchy.

Ethnicity - women of Caucasian or Asian ancestry tend to have a higher risk of tearing. Some theorize it is because of cultural or social upbringing. Others, genetics. 


Now, for the medical reasons a provider might give to perform an episiotomy:

Routine (doctor always does it) - This argument is usually given in conjunction with any of the below reasons for performing an episiotomy.

Many practitioners who believe in routine episiotomy state that a first time mom will 'nearly always tear'. I can tell you, from my experience, I have seen only 2 first-time moms naturally tear, and only one required/asked for stitches.

Other practitioners will tell you that it is easier to repair. Truth is, an episiotomy is easier for the one stitching to line up the seams... in other words, it takes less time to sew up... what they don't mention is that, although it is faster and easier for them to stitch up an episiotomy, an episiotomy is NOT easier on your body to repair. Naturally occurring tears heal faster, with less pain, less blood loss, less rates of infection, less emotional trauma, and less incidence of long term complications, such as fecal or sexual incontinence.

Best odds, talk with your care provider before birth to find out what their policies/beliefs are.

To prevent tearing - as previously discussed, there is no way for a provider to know, beyond a doubt, that a woman is going to tear until she does. And, even so, if a woman is to tear, a tear heals faster, with less pain, statistically with less degree of damage, and with less scar tissue and long term side-effects than an episiotomy does. In addition to all of this, an episiotomy has a high risk of tearing beyond the initial incision.

Truly, the only time that a woman can really benefit from the 'to prevent a tear' argument is when there is good reason to believe mom might tear anteriorly (toward the urethra or clitoris). 

Suspected large baby - If a large baby is the only reason given, it is a sad one. Many providers who perform routine episiotomies state that large babies need more room to maneuver the birth canal. Truth be told, the perineum will not hold back the birth of a large baby, only bone or mom's relaxation might. So, an episiotomy might shorten pushing by a contraction or two, but it is not going to 'rescue a large baby' from not being able to be born.

On the other hand, any care provider who has done perineal massage can tell you, a woman who is tensing against the birthing waves meant to bring baby down can hold her baby in. This is especially true for large babies or 2nd stages that are very intense.

The best a mom can do when she is told her baby may be large is to visualize her body opening gently for babies exit, remember to breath when waves come and only push when her body tells her to. Likewise, a provider skilled in deep perineal massage can be helpful in finding and releasing tense vaginal muscles during baby's descent.

This will allow for baby to have, not only room to navigate the birth canal, releasing tense vaginal muscles, but will also give the perineum time to stretch, the baby to rotate his shoulders under the pubic bone, and tissue to be soft and supple - able to stretch around any baby.

Suspected shoulder dystocia - again, all of the above same applies.

Fetal distress - This is one of only two good reasons to perform an episiotomy (the other is when an anterior tear is likely/occurring). When a baby has been showing true distress during 2nd stage and is showing further distress at crowning, an episiotomy can reduce the length of 2nd stage by a few contractions. In an emergency situation, this can be a lifesaving tool.

When a baby is truly in distress, an episiotomy can buy the provider precious moments by getting a finger hooked on babies shoulder, or mom the ability to push baby out with the next contraction/without a contraction, and without needing to wait for the perineum to stretch.

This occurrence does not happen very often, but, when it does, those few contractions can make a world of difference in baby's health.

Longer 2nd stage - Although, as stated above, episiotomies can shorten 2nd stage by a few contractions, that is all it shortens it by. If a long second stage is the only reason given, an episiotomy is only going to shorten a birth by a few moments, but postpartum recovery will be a lot more intense/extensive.

Rather than use this time to hasten birth by a few moments, this time could be better used to let mom get ready to receive her baby into her arms, encourage mom verbally, give her a drink and provide warm compresses to her bottom, and allow her to listen to her bodies cues.

Precipitous birth - If a woman is birthing very quickly, some providers will want to perform an episiotomy. Again, it is because fast births can (not will) mean a tear might occur. The funny thing is, medical texts say that, after creating the incision, a doctor or midwife should give gentle pressure against the perineum and baby's emerging head to prevent rapid or abrupt delivery, to minimize the chances of tearing beyond the incision... this is laughable as that is one of the ways to minimize the chances of a naturally occurring tear. It makes me think, 'why didn't you do that in the first place?!?!?'.  

As stated in the natural reasons, the best bet is to provide gentle counterpressure to slow a fast birth, guide mom in an easeful crowning and gentle resolution, and help mom to breath her babies head out instead of actively pushing. 

To prevent later incontinence - Studies have shown that episiotomies do more to contribute to later incontinence issues than a naturally occurring tear or an intact perineum because of the substantial risk that the episiotomy will either automatically go through muscle as well as skin, or will tear through the same.


BEST ODDS FOR 'NEITHER'
To ensure your best bet for not tearing or having an episiotomy, consider the information above. Mom's benefit from an intact perineum by eliminating the risks associated with perineal lacerations. In addition, babies benefit from an intact perineum by having their chest pressed over the intact perineum, which breaks up the mucosa in the lungs and encourages baby to expel it from their throat, mouth, and nose, before the first breath. When this occurs, many times a baby does not require suctioning and start their first breaths with a clear airway.

I consider the above information to be best consolidated in the 4 P's:


Prenatal Health - Eating a well rounded diet full of fresh fruits and veggies, especially citrus fruits and dark green and bright colored veggies, good oils and fats/omegas, and water hydration will give your tissue elasticity and healthy suppleness. Remembering to not only be attuned to your PC muscle, but also to perform regular squats will give your bottom elasticity and control for the 2nd stage.

Perineal Massage - I am not a huge proponent of clinical perineal massage during pregnancy. By clinical perineal massage, I mean the type where a woman or her partner hooks their finger into the vaginal opening and pulls/rubs at 8 and 4 o'clock positions until the perineum burns. This is not natural and can be psychologically damaging.

http://beautyandthebump.blogspot.com/

I believe that it sends the wrong message. It tells women that their body's are not capable of stretching well enough unless the woman does something unnatural to encourage it. It also sets a woman up for fear: fear if she didn't remember/know to do it prenatally that she will tear orfear that she will feel the burning that she experienced prenatally if she did perform clinical perineal massage.

What I do encourage is for women to have a healthy and active sex life during pregnancy and for she and her partner to be comfortable and familiar with her perineum and vagina through personal/pleasureable perineal massage.

If a woman is familiar with how stretchy her perineum is, if she is comfortable and knowledgeable of her vaginal muscular bands, if she is familiar with how to touch those tense bands or tendons, feel the tension, and release it or massage it away, she is more apt to do that in labor. If a woman's partner is used to the same, the woman is more apt to respond in same to similar touch/sensations during labor and birth.

Likewise, if she is familiar with what PC contraction is, she is more apt to be able to release that common tension during pushing if she can feel it with her own fingers, or feel her partner's touch and recognize the resistance and relaxation of this muscle.

Pushing - Women who push in positions that feel 'right', and are not coerced or led into certain positions, tend to have better chances of keeping their perineum intact. Likewise, when a woman can push to her body's cues, and not to the providers count, tend to stretch more readily. Women who are encouraged to be vocal if they need to, breath through those contractions that they feel the need to, and otherwise open their vocal chords for relaxation tend also to stretch more readily.

Choosing to birth in water, or at least a darkened, quiet room, encourages mom to be relaxed, and thus, her vagina and perineum is relaxed.  The warm water of a water birth helps the perineum to stretch as well, and a darkened room allows a woman to feel uninhibited, private, and safe - all of the ingredients mom needs to be relaxed.

As baby begins to crown, when a woman can reach down and touch her babies emerging head, women will often give themselves vulvar or urethral/clitoral support, pant or blow through contractions, and otherwise ease/massage their babies out.

When a woman is not able to or willing to feel her baby's emergence, often times, reminding a mom to breath or vocalize through the crowning stage will help her to stretch more easily.

I have that, women who place their fingers inside their vagina during pushing can bring their babies down more efficiently, slow crowning more readily, avoid any perineal trauma more naturally, and spontaneously catch their babies more easily. I believe that the more 'in tune' a woman is with this intense time and her body's cues, the better the outcomes we have.

Patty Ramos: http://www.doulapattiramos.com/2008/11/birth-up-close.html

Practioner's Help - a care provider who trusts in a woman's ability to birth her baby will be more patient in the absence of distress, allowing mom more time to stretch naturally. This provider will also be more apt to listen to mom's body and her own rhythm for pushing, rather than a count of 10 or purple pushing.

This care provider will also encourage mom to be in whatever position she wants to be in, and will provide/promote a safe haven for a woman to open up to the power of birthing without coercion or demands. Likewise, a practitioner can help by encouraging a relaxed vagina and perineum by providing perineal massage, warm compresses, lubrication at crowning, and perineal/anterior support during crowning and birth, if the woman would like him/her to.

CONCLUSIONS
As you can probably tell, I am very much against routine episiotomy and highly encourage women to make an educated decision regarding this procedure before the option presents itself. I always encourage the mom's I work with to talk with their care providers before birth to find out what their provider's stance is and to talk about any inconsistencies with them ahead of time.

Treating women like mothers during their labors and births, giving their bodies the benefit of the doubt when they take a few moments longer, in the absence of fetal or maternal distress, can allow a woman to claim her birth and baby as a positively transforming act, rather than a traumatic experience.

As a woman who has had both an episiotomy (1st birth) and skid marks (last birth, and having been told that my scar tissue was so extensive that I 'would definitely' tear with any subsequent births (which I never did), I am an avid supporter and believer in all of the practices herein to minimize the possibility of a naturally occuring tear occurring. Would I rather tear or have an episiotomy? Neither. But, if push comes to shove (or, more accurately, if push comes to the risk of tearing), I would rather tear.

Remember, if you have done all that you can to ensure that you will have an intact perineum and you still tear, remember to trust that your body did only what it needed to to birth your baby. 

Take a moment to read this woman's beautiful birth story of a large baby with not even a skid mark. She talks about how she believes she was able to ease Laslo's birth and even shares a birth montage. Enjoy. 

RESOURCES/FURTHER READING

• Evidence Report/Technology Assessment No. 112, The Use of Episiotomy in Obstetrical Care: A Systematic Review (AHRQ Publication No. 05-E009-2).
• Lemay, Gloria "Midwife's Guide to an Intact Perineum," Midwifery
  Today Issue 59
• Obstetric Myths Versus Research Realities, Chapter 14: Episiotomy
  
• Murray W. Enkin MD, FRCS(C), D.J. Hunter MD, FRCOG, FRCS(C), Laura Snell RN, SCM (1984)
• EPISIOTOMY: EFFECTS OF A RESEARCH PROTOCOL ON CLINICAL PRACTICE
• Birth 11 (3), 145–146. doi:10.1111/j.1523-536X.1984.tb00768.x
• Hartmann K, Viswanathan M, Palmieri R, Gertlehner G, Thorp J, Lohr KN. Outcomes of routine episiotomy: a systematic review.JAMA 2005;293:2141-8.
• Saying No to Episiotomy : Getting through Labor and Delivery in One Piece By Elizabeth Bruce, Mothering Magazine, Issue 104, January/February 2001
• University of North Carolina, Center for Women's Health Research. Routine episiotomy does not provide benefits: the importance of asking questions about common things.
• The Second Stage of Labor
  
• Viswanathan M, Hartmann K, Palmieri R., Lux L, Swinson T, Lohr KN, Gartlehner G, Thorp J. The use of episiotomy in obstetrical care: a systematic review; summary. Agency for Healthcare Research and Quality (Evidence Report/Technology Assessment: Number 112.)
• Carroli G, Belizan J. Episiotomy for vaginal birth. Cochrane Database of Systematic Reviews 1997, Issue 2. Art. No.: CD000081. DOI: 10.1002/14651858.CD000081
  
• Roberts CL, Tracy S, Peat B. Rates for obstetric intervention among private and public patients in Australia: a population based descriptive study. BMJ. 2000;321:137–141.
• Senate Community Affairs Reference Committee. Rocking the cradle: a report of childbirth procedures. Canberra: Commonwealth of Australia; 1999. www.aph.gov.au/senate_ca.
• Roberts JM. Recent advances: Obstetrics. BMJ. 2000;321:33–35.
• Albers, L. L.; Sedler, K. D.; Bedrick, E. J.; et al., D; Peralta, P (2005). "Midwifery care measures in the second stage of labor and reduction of genital tract trauma at birth: a randomized trial". Journal of Midwifery & Women's Health 50 (5): 365–372. doi:10.1016/j.jmwh.2005.05.012. PMID 16154062
• 10% Primipara Sutured Tear rate in the absence of episiotomy. Birth 2008;35(2):167.
• Woolley RJ. Benefits and risks of episiotomy: A review of the English-language literature since 1980. Part I. Obstet Gynecol Survey 1995; 50:806-820
• Woolley RJ. Benefits and risks of episiotomy: A review of the English-language literature since 1980. Part II. Obstet Gynecol Survey 1995; 50:821-835