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VOL. 107, NO. 4, APRIL 2006 OBSTETRICS & GYNECOLOGY 9 5 7
ACOG
PRACTICE
BULLETINCLINICALMANAGEMENTGUIDELINES FOR
OBSTETRICIANGYNECOLOGISTS
NUMBER71, APRIL2006
This Practice Bulletin was
developed by the ACOG Com-
mittee on Practice Bulletins
Obstetrics with the assistance
of John T. Repke, MD. The in-
formation is designed to aid
practitioners in making deci-
sions about appropriate obstet-
ric and gynecologic care. These
guidelines should not be con-
strued as dictating an exclusivecourse of treatment or proce-
dure. Variations in practice may
be warranted based on the
needs of the individual patient,
resources, and limitations
unique to the institution or type
of practice.
EpisiotomyEpisiotomy is one of the most commonly performed procedures in obstetrics. In2000, approximately 33% of women giving birth vaginally had an episiotomy
(1). Historically, the purpose of this procedure was to facilitate completion of
the second stage of labor to improve both maternal and neonatal outcomes.
Maternal benefits were thought to include a reduced risk of perineal trauma,
subsequent pelvic floor dysfunction and prolapse, urinary incontinence, fecal
incontinence, and sexual dysfunction. Potential benefits to the fetus were
thought to include a shortened second stage of labor resulting from more rapid
spontaneous delivery or from instrumented vaginal delivery. Despite limited
data, this procedure became virtually routine resulting in an underestimation of
the potential adverse consequences of episiotomy, including extension to athird- or fourth-degree tear, anal sphincter dysfunction, and dyspareunia. The
purpose of this document is to examine the risks and benefits of episiotomy
and to make recommendations regarding the use of this procedure in current
obstetric practice.
Background
History
Episiotomy has been described in the medical literature for more than 300
years, but it was not until the 1920s, with the publication of papers by DeLee
(2) and Pomeroy (3), that more routine use of episiotomy became accepted.
However, there was certainly not unanimity about the utility of this approach at
that time (4). The shift to in-hospital deliveries in the 20th century was associ-
ated with decreased morbidity and an increase in the use of episiotomy and pro-
liferation of many other obstetric practices (eg, use of forceps, use of cesarean
delivery, use of anesthesia). More recently, in 1992 more than 1.6 million epi-
siotomies were performed in the United States, with a background cesarean
delivery rate of 22.3%. In 2003, 716,000 episiotomies were performed with a
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9 5 8 ACOG Practice Bulletin Episiotomy OBSTETRICS & GYNECOLOGY
background cesarean delivery rate of 27.5%, suggesting
that use of this procedure in obstetrics is decreasing (5, 6).
Techniques of Episiotomy
In general, two types of episiotomy have been described:
the median (or midline or medial) episiotomy and the
mediolateral episiotomy. In the United States, the more
commonly used technique is the median episiotomy. Itgained popularity because it is easy to perform and to
repair. Postpartum pain is reported to be reduced with
this technique, as is postpartum dyspareunia (4). Median
episiotomy, however, is associated with a greater risk of
extension to include the anal sphincter (third-degree
extension) or rectum (fourth-degree extension) (710).
Mediolateral episiotomy, an incision at least 45
degrees from the midline, is more commonly performed
outside the United States and is favored by some because
it maximizes perineal space for delivery while reducing
the likelihood of third- or fourth-degree extension (8, 11).
Reported disadvantages of the mediolateral procedureinclude difficulty of repair, greater blood loss, and, pos-
sibly, more early postpartum discomfort (4).
Technique of Repair
The median episiotomy tends to be a simpler incision to
repair, even if it requires repair of the rectal mucosa and
anal sphincter. For either technique, a two-layered clo-
sure has been shown to decrease postpartum pain and
healing complications compared with a three-layer clo-
sure (1214). Compared with interrupted, transcutaneous
suturing, one study reported less postpartum pain at
3 months with continuous subcutaneous suturing (15).Although a second study reported no difference (16),
both studies found a lower need for suture removal with
the continuous method (15, 16).
Various suture materials have been used for episiot-
omy repair, with limited data to suggest the superiority of
one type of material over another. A minimally reactive,
absorbable polyglycolic acid suture may be preferable to
chromic catgut because there may be less perineal pain and
dyspareunia (13, 16, 17). The drawback of using less reac-
tive materials is a slower resorption profile that rarely may
result in the need for suture removal (18, 19). For this rea-
son, many clinicians now use monofilament absorbable
sutures or more rapidly absorbable polyglactin derivatives.
Complications
Bleeding from the episiotomy site is one of the most fre-
quent complications. Such bleeding often is easily con-
trolled with conservative measures and compression, but
substantial hematoma formation may occur. Infection
also may complicate episiotomy healing. In most cases,
such infections are localized and may resolve with per-
ineal wound care. In rare cases, an abscess may form,
which will result in either the need for disruption of the
repair to allow for evacuation of the abscess or sponta-
neous breakdown of the repair. In extreme cases, infec-
tions such as necrotizing fasciitis can cause maternal
death if not effectively evaluated and treated. In cases of
less severe infection with wound breakdown, severalapproaches can be used. For superficial breakdowns not
involving the rectum or anal sphincter, expectant man-
agement with perineal care may allow for spontaneous
healing to occur over a period of several weeks. For more
extensive breakdowns, or when the logistics of many fol-
low-up visits may be prohibitive, primary closure of the
defect may be attempted. Data suggest that early closure
of episiotomy dehiscence in properly selected cases may
be appropriate (20). In rare cases, inadequately repaired
episiotomies may lead to rectovaginal fistula formation
(21). Repair of such defects can be challenging, depend-
ing on size and location, and should be repaired by some-
one familiar with fistula repair techniques.
Clinical Considerations andRecommendations
What are the indications for episiotomy?
The indications for episiotomy are varied and based large-
ly on clinical opinion. It has been suggested that episiot-
omy is indicated in cases where expediting delivery in the
second stage of labor is warranted or where the likelihood
of spontaneous laceration seems high. Such clinical cir-
cumstances would include a nonreassuring fetal heart rate
pattern, operative vaginal delivery, shoulder dystocia, and
cases where the perineal body is thought to be unusually
short. The data supporting these claims are largely
descriptive or anecdotal. Several trials suggest the lack of
evidence supporting use of episiotomy in these circum-
stances. Two recent trials also failed to show that epi-
siotomy improved neonatal outcome, provided better
protection of the perineum, or facilitated operative vaginal
delivery (22, 23). Current data and clinical opinion sug-
gest that there are insufficient objective evidence-based
criteria to recommend episiotomy, and especially routineuse of episiotomy, and that clinical judgment remains the
best guide for use of this procedure (24).
How does episiotomy affect the rate and
severity of perineal lacerations?
A systematic review of seven trials comparing routine
episiotomy with restrictive use of the procedure found
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VOL. 107, NO. 4, APRIL 2006 ACOG Practice Bulletin Episiotomy 9 5 9
that an intact perineum was more common in the restrict-
ed group, but anterior labial lacerations also were more
common. There were no differences in rectal injuries
(24). Another systematic review suggests that routine
mediolateral episiotomy compared with restricted use
does not protect against anal sphincter trauma, and medi-
an episiotomy caused more anal sphincter tears (25).
Nonetheless, anterior lacerations are not associated withan increased need for suturing, suggesting that these
tears are less severe than posterior tears. Thus, restrictive
use of episiotomy appears to reduce the likelihood of
perineal lacerations.
Can episiotomy prevent pelvic muscle relax-
ation leading to incontinence?
There is consensus that the risk of incontinence increas-
es with increasing degrees of pelvic trauma. One study
of extended episiotomies demonstrated that the occur-
rence of a fourth-degree extension was more highly asso-
ciated with anal incontinence (26). The single greatest
risk factor for third- or fourth-degree lacerations seems
to be the performance of a median episiotomy, suggest-
ing that avoiding episiotomy itself may be the best way
to minimize the risk of subsequent extensive damage to
the perineum (27). In four cohort studies, investigators
asked women about anal incontinence episodes; one
study also included physical examinations (25, 2830).
Episiotomy was not found to be associated with reduced
risk of incontinence of stool or flatus (24). Similarly, in
another study of perineal muscle function, women who
had an episiotomy had less recovery of postpartum per-
ineal muscle function than did women who did notundergo episiotomy, leading the investigators to con-
clude that use of episiotomy for preservation of perineal
muscle function is not warranted (31). A prospective
study of 519 primiparous women compared those who
had a mediolateral episiotomy with those who had an
intact perineum or first- or second-degree lacerations
(28). No differences in urinary or anal incontinence or
genital prolapse were reported. A systematic review of
routine versus restrictive episiotomy found no evidence
to support episiotomy in preventing pelvic floor damage
(24).
How does episiotomy affect postpartum pain
and sexual functioning?
Postpartum recovery is an area of obstetrics that lacks
systematic study and analysis. Recovery depends on
many factors, and a number of investigators have
attempted to determine what factors, if any, lead to more
expeditious recovery and return of normal function.
Whether episiotomy contributes to immediate postpar-
tum pain is debated. One study suggests that duration of
the second stage of labor correlated most closely with
acute postpartum pain (32), whereas other studies sug-
gest that immediate postpartum pain is well correlated
with degree of perineal trauma and, therefore, with epi-
siotomy use (27, 33, 34). The most studied measure of
postpartum sexual function is the time from deliveryuntil resumption of sexual intercourse. Most data sug-
gest that 90% of women in the postpartum period have
resumed intercourse within 34 months of delivery (34).
In at least two studies, episiotomy was not identified as
an independent risk factor for dyspareunia or delayed
return to sexual activity when compared with equally
severe perineal trauma in women who did not have an
episiotomy (34, 35). Prospective cohort studies did not
find differences in dyspareunia or resumption of inter-
course at 3 months (24).
Another aspect of postpartum discomfort relates to
method of episiotomy closure or repair of a spontaneous
laceration. A number of trials have reported on different
techniques of perineal closure aimed at reducing post-
partum pain and facilitating expeditious healing (12, 13,
36). Newer approaches using more rapidly absorbing
synthetic sutures, either braided or monofilament, have
been reported. Larger trials are needed before a conclu-
sion can be reached about their efficacy (13, 15, 37, 38).
What are the fetal benefits of episiotomy?
Proposed fetal benefits of episiotomy include cranial
protection, especially for premature infants, reduced
perinatal asphyxia, less fetal distress, better Apgar
scores, less fetal acidosis, and reduced complications
from shoulder dystocia. Despite these claims, few data
are available to support any of them. Even the presump-
tion that episiotomy shortens the second stage of labor
has not been conclusively shown.
Although increasing perineal space would seem
intuitively beneficial with respect to the prevention and
management of shoulder dystocia, few data other than
anecdotes support this notion. A systematic review of the
literature (13) found only one study that addressed this
issue and concluded that the use of episiotomy had no
influence on the risk of shoulder dystocia (39). However,
if shoulder dystocia occurs, episiotomy may be useful tofacilitate its management. No data support or refute the
benefits of episiotomy with operative vaginal delivery.
Which type of episiotomy (median or medio-
lateral) is favored?
Median episiotomies are associated with a greater risk of
extension into the rectum and compromise of the exter-
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9 6 0 ACOG Practice Bulletin Episiotomy OBSTETRICS & GYNECOLOGY
Summary ofRecommendations andConclusions
The following recommendation and conclusion
are based on good and consistent scientific evi-
dence (Level A):
Restricted use of episiotomy is preferable to routine
use of episiotomy.
Median episiotomy is associated with higher rates of
injury to the anal sphincter and rectum than is medio-
lateral episiotomy.
The following recommendation and conclusion
are based on limited or inconsistent scientific evi-
dence (Level B):
Mediolateral episiotomy may be preferable to medi-
an episiotomy in selected cases.
Routine episiotomy does not prevent pelvic floor
damage leading to incontinence.
Proposed PerformanceMeasureFor patients with episiotomy, the percentage for whom the
indication for episiotomy is included in the delivery notes
References1. Martin JA, Hamilton BE, Ventura SJ, Menacker F, Park
MM. Births: final data for 2000. Natl Vital Stat Rep2002;50(5):1101. (Level II-3)
2. DeLee JB. The prophylactic forceps operation. Am JObstet Gynecol 1920;1:3444. (Level III)
3. Pomeroy RH. Shall we cut and reconstruct the perineumfor every primipara? Am J Obstet Dis Women Child1918;78:21120. (Level III)
4. Thacker SB, Banta HD. Benefits and risks of episiotomy:an interpretive review of the English language literature,1860-1980. Obstet Gynecol Surv 1983;38:32238. (Level
III)
5. DeFrances CJ, Hall MJ, Podgornik MN. 2003 NationalHospital Discharge Survey. Advance data; No. 359.Hyattsville (MD): National Center for Health Statistics;2005. Available at: http://www.cdc.gov/nchs/data/ad/ad359.pdf. Retrieved December 29, 2005. (Level II-3)
6. Martin JA, Hamilton BE, Sutton PD, Ventura SJ,Menacker F, Munson ML. Births: final data for 2003. NatlVital Stat Rep 2005;54(2):1116. (Level II-3)
nal anal sphincter muscle (7). Mediolateral episiotomies
have been linked to greater postpartum pain, more blood
loss, more difficulty in effecting proper repair, and more
dyspareunia (4), especially when compared with sponta-
neous tears (28, 40). Also, because of the potential for
greater expansion of the pelvic floor with mediolateral
episiotomy, it has been suggested that use of this proce-
dure may provide more protection against the develop-ment of incontinence (41). Multiple studies using an
endpoint of avoiding anal sphincter or rectal injury have
demonstrated that mediolateral episiotomy is superior to
median episiotomy (9, 42, 43). However, there may be
other drawbacks to the use of mediolateral episiotomy,
including increased perineal trauma not involving the
sphincter (44). There does not appear to be evidence to
support a protective effect of mediolateral episiotomy
with respect to subsequent development of genital pro-
lapse (28). In addition, although the data are insufficient
to determine the superiority of either approach, data do
suggest that both median and mediolateral episiotomieshave similar outcomes, including pain from the incision
and time to resumption of intercourse (7).
The timing of episiotomy has long been the subject
of debate (2, 3). There are no data to show that early epi-
siotomy results in decreased pelvic floor trauma. It has
been demonstrated that episiotomy, whether median or
mediolateral, is associated with increased maternal blood
loss at the time of delivery (45).
Should episiotomy be routine or restricted in
clinical practice?
The best available data do not support liberal or routine
use of episiotomy. Nonetheless, there is a place for epi-
siotomy for maternal or fetal indications, such as avoid-
ing severe maternal lacerations or facilitating or
expediting difficult deliveries. According to a recent sys-
tematic evidence review (24), although episiotomy is per-
formed in approximately 3035% of vaginal births in the
United States, prophylactic use of episiotomy does not
appear to result in maternal or fetal benefit. Another sys-
tematic review comparing routine episiotomy with
restrictive use reported that the group routinely using epi-
siotomy had an overall incidence of 72.7%, versus 27.6%
in the restricted-use group (46). The restricted-use group
had significantly lower risks of posterior perineal trauma,
suturing, and healing complications, but a significant
increase in anterior perineal trauma. No statistically sig-
nificant differences were reported for severe vaginal or
perineal trauma, dyspareunia, or urinary incontinence,
leading the reviewers to conclude that restrictive-use pro-
tocols are preferable to routine use of this procedure.
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VOL. 107, NO. 4, APRIL 2006 ACOG Practice Bulletin Episiotomy 9 6 1
7. Coats PM, Chan KK, Wilkins M, Beard RJ. A comparisonbetween midline and mediolateral episiotomies. Br J
Obstet Gynaecol 1980;87:40812. (Level II-1)
8. Bodner-Adler B, Bodner K, Kaider A, Wagenbichler P,Leodolter S, Husslein P, et al. Risk factors for third-degreeperineal tears in vaginal delivery, with an analysis of epi-siotomy types. J Reprod Med 2001;46:7526. (Level II-3)
9. Riskin-Mashiah S, OBrian Smith E, Wilkins IA. Risk fac-
tors for severe perineal tear: can we do better? Am JPerinatol 2002;19:22534. (Level II-2)
10. Helwig JT, Thorp JM Jr, Bowes WA Jr. Does midline epi-siotomy increase the risk of third- and fourth-degree lac-erations in operative vaginal deliveries? Obstet Gynecol1993;82:2769. (Level II-2)
11. Shiono P, Klebanoff MA, Carey JC. Midline episiotomies:more harm than good? Obstet Gynecol 1990;75:76570.(Level II-2)
12. Oboro VO, Tabowei TO, Loto OM, Bosah JO. A multi-centre evaluation of the two-layered repair of postpartumperineal trauma. J Obstet Gynaecol 2003;23:58. (Level I)
13. Grant A, Gordon B, Mackrodt C, Fern E, Truesdale A,
Ayers S. The Ipswich childbirth study: one year followupof alternative methods used in perineal repair. BJOG2001;108:3440. (Level II-2)
14. Gordon B, Mackrodt C, Fern E, Truesdale A, Ayers S,Grant A. The Ipswich Childbirth Study: I. A randomisedevaluation of two stage postpartum perineal repair leavingthe skin unsutured. Br J Obstet Gynaecol 1998;105:43540. (Level I)
15. Kettle C, Hills RK, Jones P, Darby L, Gray R, Johanson R.Continuous versus interrupted perineal repair with stan-dard or rapidly absorbed sutures after spontaneous vaginalbirth: a randomised controlled trial. Lancet 2002;359:221723. (Level I)
16. Mahomed K, Grant A, Ashurst H, James D. TheSouthmead perineal suture study. A randomized compari-son of suture materials and suturing techniques for repairof perineal trauma. Br J Obstet Gynaecol 1989;96:127280. (Level I)
17. Mackrodt C, Gordon B, Fern E, Ayers S, Truesdale A,Grant A. The Ipswich Childbirth Study: 2. A randomisedcomparison of polyglactin 910 with chromic catgut forpostpartum perineal repair. Br J Obstet Gynaecol 1998;105:4415. (Level I)
18. Grant A. The choice of suture materials and techniques forrepair of perineal trauma: an overview of the evidencefrom controlled trials. Br J Obstet Gynaecol 1989;96:12819. (Level III)
19. Ketcham KR, Pastorek JG 2nd, Letellier RL. Episiotomyrepair: chromic versus polyglycolic acid suture. SouthMed J 1994;87:5147. (Level III)
20. Hankins GD, Hauth JC, Gilstrap LC 3rd, Hammond TL,Yeomans ER, Snyder RR. Early repair of episiotomydehiscence. Obstet Gynecol 1990;75:4851. (Level III)
21. Barranger E, Haddad B, Paniel BJ. Fistula in ano as a rarecomplication of mediolateral episiotomy: report of threecases. Am J Obstet Gynecol 2000;182:7334. (Level III)
22. Myles TD, Santolaya J. Maternal and neonatal outcomesin patients with prolonged second stage of labor. ObstetGynecol 2003;102:528. (Level II-3)
23. Bodner-Adler B, Bodner K, Kimberger O, WagenbichlerP, Mayerhofer K. Management of the perineum duringforceps delivery. Association of episiotomy with the fre-quency and severity of perineal trauma in women under-going forceps delivery. J Reprod Med 2003;48:23942.
(Level II-3)24. Hartmann K, Viswanathan M, Palmieri R, Gartlehner G,
Thorp J, Lohr KN. Outcomes of routine episiotomy: a sys-tematic review. JAMA 2005;293:21418. (Level III)
25. Eason E, Labrecque M, Wells G, Feldman P. Preventingperineal trauma during childbirth: a systematic review.Obstet Gynecol 2000;95:46471. (Meta-Analysis)
26. Fenner DE, Genberg B, Brahma P, Marek L, DeLanceyJO. Fecal and urinary incontinence after vaginal deliverywith anal sphincter disruption in an obstetrics unit in theUnited States. Am J Obstet Gynecol 2003;189:154350.(Level II-3)
27. Robinson JN, Norwitz ER, Cohen AP, McElrath TF,Lieberman ES. Epidural analgesia and third- and fourth-degree lacerations in nulliparas. Obstet Gynecol 1999;94:25962. (Level II-3)
28. Sartore A, De Seta F, Maso G, Pregazzi R, Grimaldi E,Guaschino S. The effects of mediolateral episiotomy onpelvic floor function after vaginal delivery. ObstetGynecol 2004;103:66973. (Level II-2)
29. MacArthur C, Bick DE, Keighley MR. Faecal inconti-nence after childbirth. Br J Obstet Gynaecol 1997;104:4650.
30. Walsh CJ, Mooney EF, Upton GJ, Motson RW. Incidenceof third-degree perineal tears in labour and outcome afterprimary repair. Br J Surg 1996;83:21821. (Level II-2)
31. Fleming N, Newton ER, Roberts J. Changes in postpartum
perineal muscle function in women with and without epi-siotomies. J Midwifery Womens Health 2003;48:539.(Level II-2)
32. Thranov I, Kringelbach AM, Melchior E, Olsen O,Damsgaard MT. Postpartum symptoms. Episiotomy ortear at vaginal delivery. Acta Obstet Gynecol Scand 1990;69:115. (Level II-3)
33. Macarthur AJ, Macarthur C. Incidence, severity, and deter-minants of perineal pain after vaginal delivery: a prospec-tive cohort study. Am J Obstet Gynecol 2004;191:1199204. (Level II-2)
34. Signorello LB, Harlow BL, Chekos AK, Repke JT.Postpartum sexual functioning and its relationship to per-ineal trauma: a retrospective cohort study of primiparouswomen. Am J Obstet Gynecol 2001;184:8817; discussion88890. (Level II-2)
35. Abraham S, Child A, Ferry J, Vizzard J, Mira M. Recoveryafter childbirth: a preliminary prospective study. Med JAust 1990;152:912. (Level II-2)
36. Isager-Sally L, Legarth J, Jacobsen B, Bostofte E.Episiotomy repairimmediate and long-term sequelae. Aprospective randomized study of three different methodsof repair. Br J Obstet Gynaecol 1986;93:4205. (Level I)
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9 6 2 ACOG Practice Bulletin Episiotomy OBSTETRICS & GYNECOLOGY
The MEDLINE database, the Cochrane Library, and theAmerican College of Obstetricians and Gynecologists owninternal resources and documents were used to conduct aliterature search to locate relevant articles published be-tween January 1985 and May 2005. The search was re-stricted to articles published in the English language.Priority was given to articles reporting results of originalresearch, although review articles and commentaries also
were consulted. Abstracts of research presented at sympo-sia and scientific conferences were not considered adequatefor inclusion in this document. Guidelines published by or-ganizations or institutions such as the National Institutes ofHealth and ACOG were reviewed, and additional studieswere located by reviewing bibliographies of identified arti-cles. When reliable research was not available, expert opin-ions from obstetriciangynecologists were used.
Studies were reviewed and evaluated for quality accordingto the method outlined by the U.S. Preventive Services TaskForce:
I Evidence obtained from at least one properly de-signed randomized controlled trial.
II-1 Evidence obtained from well-designed controlled
trials without randomization.II-2 Evidence obtained from well-designed cohort orcasecontrol analytic studies, preferably from morethan one center or research group.
II-3 Evidence obtained from multiple time series with orwithout the intervention. Dramatic results in uncon-trolled experiments also could be regarded as thistype of evidence.
III Opinions of respected authorities, based on clinicalexperience, descriptive studies, or reports of expertcommittees.
Based on the highest level of evidence found in the data,recommendations are provided and graded according to thefollowing categories:
Level ARecommendations are based on good and consis-
tent scientific evidence.Level BRecommendations are based on limited or incon-sistent scientific evidence.
Level CRecommendations are based primarily on con-sensus and expert opinion.
Copyright April 2006 by the American College of Obstetricians and
Gynecologists. All rights reserved. No part of this publication may be
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from the publisher.
Requests for authorization to make photocopies should be directed to
Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA
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The American College of Obstetricians and Gynecologists
409 12th Street, SW, PO Box 96920, Washington, DC 20090-6920
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Episiotomy. ACOG Practice Bulletin No. 71. American College ofObstetricians and Gynecologists. Obstet Gynecol 2006;107:95762.
37. Upton A, Roberts CL, Ryan M, Faulkner M, Reynolds M,Raynes-Greenow C. A randomised trial, conducted bymidwives, of perineal repairs comparing a polyglycolicsuture material and chromic catgut. Midwifery 2002;18:2239. (Level I)
38. Bowen ML, Selinger M. Episiotomy closure comparingenbucrilate tissue adhesive with conventional sutures. Int JGynaecol Obstet 2002;78:2015. (Level II-1)
39. Nocon JJ, McKenzie DK, Thomas LJ, Hansell RS.Shoulder dystocia: an analysis of risks and obstetricmaneuvers. Am J Obstet Gynecol 1993;168:17327; dis-cussion 17379. (Level II-3)
40. Rockner G, Wahlberg V, Olund A. Episiotomy and per-ineal trauma during childbirth. J Adv Nurs 1989;14:2648.(Level II-2)
41. Poen AC, Felt-Bersma RJ, Dekker GA, Deville W, CuestaMA, Meuwissen SG. Third degree obstetric perineal tears:risk factors and the preventive role of mediolateral episiot-omy. Br J Obstet Gynaecol 1997;104:5636. (Level II-2)
42. Signorello LB, Harlow BL, Chekos AK, Repke JT.Midline episiotomy and anal incontinence: a retrospectivecohort study. BMJ 2000;320:8690. (Level II-2)
43. De Leeuw JW, Vierhout ME, Struijk PC, Hop WC,Wallenburg HC. Anal sphincter damage after vaginaldelivery: functional outcome and risk factors for fecalincontinence. Acta Obstet Gynecol Scand 2001;80:8304.(Level II-2)
44. Anthony S, Buitendijk SE, Zondervan KT, van Rijssel EJ,Verkerk PH. Episiotomies and the occurrence of severeperineal lacerations. Br J Obstet Gynaecol 1994;101:10647. (Level II-3)
45. Combs CA, Murphy EL, Laros RK Jr. Factors associatedwith postpartum hemorrhage with vaginal birth. ObstetGynecol 1991;77:6976. (Level II-2)
46. Carroli G, Belizan J. Episiotomy for vaginal birth. The
Cochrane Database of Systematic Reviews 1999, Issue 3.Art. No.: CD000081. DOI: 10.1002/14651858.CD000081.(Meta-Analysis)