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Blunt expansion of the low transverse
uterine incision at cesarean delivery:
a randomized comparison of 2 techniques
Antonella Cromi, MD, PhD; Fabio Ghezzi, MD; Edoardo Di Naro, MD;
Gabriele Siesto, MD; Giuseppe Loverro, MD; Pierfrancesco Bolis, MD
OBJECTIVE: The purpose of this study was to compare 2 methods of
expansion of the uterine incision at the time of cesarean delivery.
STUDY DESIGN: Women who underwent a low-segment transverse ce-
sarean delivery were assigned randomly to have the blunt expansion of
the uterine incision by the physician separating the fingers either in a
transversal direction or in a cephalad-caudad direction. The primary
outcome measure was the incidence of unintended extensions.
RESULTS: The transversal (n ⫽ 406) and cephalad-caudad (n ⫽ 405)
expansion groups were similar with regard to patient characteristics,
indication to surgery, type of anesthesia, and proportion of emergency
procedures. No difference in the need for transfusions (0.7% vs 0.7%;
P ⫽ 1.0) or estimated blood loss (440 ⫾ 341 vs 398 ⫾ 242 mL; P ⫽
.09) was noted. The incidence of unintended extension (7.4% vs 3.7%;
P ⫽ .03) and blood loss of ⬎1500 mL (2.0% vs 0.2%; P ⫽ .04) was
significantly higher in the transversal expansion group, compared with
the cephalad-caudad group. Transversal expansion was an independent contributor to unintended extension and blood loss of ⬎1500
mL.
CONCLUSION: Because it is associated with less risk of unintended
extension and excessive blood loss, expansion of the uterine incision
with a cephalad-caudad traction should be preferred to transversal expansion when a cesarean delivery is performed.
Key words: bleeding, cesarean delivery, expansion of uterine
incision, extension, surgical technique
Cite this article as: Cromi A, Ghezzi F, Di Naro E, Siesto G, Loverro G, Bolis P. Blunt expansion of the low transverse uterine incision at cesarean delivery: a
randomized comparison of 2 techniques. Am J Obstet Gynecol 2008;199:292.e1-292.e6.
C
esarean delivery is the major surgical procedure most commonly performed in the western world, and the cesarean delivery rate continues to
increase, despite efforts to constrain the
From the Department of Obstetrics and
Gynecology, University of Insubria, Varese
(Drs Cromi, Ghezzi, Siesto, and Bolis), and
the Third Department of Obstetrics and
Gynecology, University of Bari, Bari (Drs Di
Naro and Loverro), Italy.
This research was presented at the 28th
annual meeting of the Society for Maternal–
Fetal Medicine, Dallas, TX, Jan. 28-Feb. 2,
2008.
Received Feb. 29, 2008; revised June 1, 2008;
accepted July 8, 2008.
Reprints: Antonella Cromi, MD, Department of
Obstetrics and Gynecology, University of
Insubria, Piazza Biroldi 1, 21100 Varese, Italy.
[email protected].
0002-9378/$34.00
© 2008 Mosby, Inc. All rights reserved.
doi: 10.1016/j.ajog.2008.07.013
For Editors’ Commentary,
see Table of Contents
292.e1
trend for more and more operative abdominal deliveries. The procedure is
performed so frequently that even modest differences in outcome, which result
from an improved technique, are likely
to have relevant cost and community
effects.
The main aspects of the surgical approach to low-transverse cesarean delivery have not changed much since it was
first described by Kerr1 in 1926. However, over the years minor variations of
each surgical step have been introduced,
and national surveys report that a wide
range of techniques are used in current
practice.2 Many technical steps are routinely used because they have been accepted for years and simply handed on
from trainer to trainee, without questioning the legitimacy of such approaches, which often are based on clinically sound recommendations but are
not truly evidence based.3
Extension of the uterine incision at cesarean delivery usually is performed either sharply by cutting laterally and then
American Journal of Obstetrics & Gynecology SEPTEMBER 2008
slightly upward with bandage scissors or
bluntly by tearing the myometrium with
the fingers.4,5 Blunt expansion is derived
commonly by when the surgeon pulls the
index fingers apart from medial to lateral
and cephalad at the same time.
Anatomic studies indicate that the
oblique interlacing muscular fibers of
the middle layer of the myometrium in
the body of the uterus assume an horizontal course inferiorly towards the istmus.6 Thus, because circular and transversely running muscular bundles
dominate the lower uterine segment,
uterine incision can be widened transversally by separation of the index fingers
of the surgeon in the midline in a cephalad-caudad direction as well.7 We speculated that expansion of uterine incision
with a vertical traction might have 2 potential advantages. The first is to avoid
greater forward extension of the distal
incision because of lack of control of the
force magnitude that is applied by the
surgeon’s fingers at the lateral edges of
the incision. The second is to minimize
tissue trauma by allowing myometrium
dissection along natural tissue planes.
SMFM Papers
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FIGURE 1
Methods of expansion of the uterine incision
A, Women in the transversal expansion group had the uterine incision extended by the insertion of
both index fingers of the operator into the opening who then pulled the finger apart laterally and
slightly cephalad. B, In the cephalad-caudad expansion group, a transverse opening of the lower
uterine segment was created by separation of the fingers of the surgeon in a cephalad-caudad
direction along the midline.
Cromi. Blunt expansion of the low transverse uterine incision at cesarean delivery. Am J Obstet Gynecol 2008.
We therefore designed a study to compare 2 methods of expanding the uterine
incision (blunt extension by separating the
fingers in a transversal vs cephalad-caudad
direction) at the time of cesarean delivery.
M ATERIALS AND M ETHODS
Between November 2005 and July 2007, all
women who underwent a low-segment
transverse cesarean delivery after 30 weeks
of gestation were offered the opportunity
to participate in this trial. The study was
conducted at a university referral center
that manages approximately 1800 deliveries annually. The cesarean delivery rate in
our unit approaches 30%. The population
that is served by the hospital roughly corresponds to the national Italian population
in terms of social class distribution and
ethnicity. The study was approved by the
Institutional Review Board of University
of Insubria.
All patients who were scheduled for an
elective procedure were enrolled on admission on the morning of the procedure, after providing written informed
consent. To overcome the problem of in-
sufficient time to counsel the patient
properly in case of emergency procedure, written and verbal information
about the trial were provided to all
women who were admitted to hospital in
labor or for induction of labor or for obstetrics complication intervention after
30 weeks of gestation. In case of cesarean
delivery performed for emergency indications, participants were enrolled at the
time that the decision to perform the
procedure was made.
Volunteers were assigned randomly to
have the blunt expansion of the uterine incision using either a transversal traction
(transversal group) or a cephalad-caudad
traction (cephalad-caudad group). Allocation was on 1:1 basis with a block-randomized computer-generated list. The
surgical steps up to the point of uterine
incision extension were accomplished in
a standard fashion. Briefly, skin incision
was made with a Pfannenstiel incision;
subcutaneous incision and opening were
performed with the scalpel as little as
possible, with dissection of tissue layers
bluntly from medial to lateral; a small
transversal opening of the fascia was
made with the scalpel and extended laterally with scissors; the fascial sheath was
dissected off the recti muscles either
sharply or bluntly; the peritoneum was
opened bluntly; a bladder flap was not
created routinely; uterine incision was
initiated with the scalpel to incise the
lower uterine segment transversely for
1-2 cm in the midline; and the cavity was
entered bluntly with a fingertip. At this
time point, women who were assigned to
the transversal expansion technique had
the initial uterine incision extended
when the operator’s index fingers were
pulled apart from medial to lateral and
slightly cephalad. In the cephaladcaudad group, uterine incision was widened by separation of the operator’s
forefingers in a cephalad-caudad direction along the midline (Figure 1).
The remainder of the procedure was
then completed in a standard fashion.
Surgical steps included manual delivery
of the fetus, spontaneous delivery of the
placenta, and uterine exteriorization.
Both techniques for opening the lower
uterine segment ultimately resulted in a
low-transverse uterine incision that was
closed with a continuous nonlocking
single layer technique. This was followed
by continuous nonlocking closure of the
fascia with delayed-absorbable suture,
suture closure of subcutaneous fat in
women with ⱖ2 cm subcutaneous thickness, and skin closure by either staples or
absorbable subcuticular suture.
Maternal demographics, indication
for surgery, stage of labor, type of anesthesia, and intraoperative details were
recorded in a computerized database
that was maintained by trained residents.
The adherence to treatment assignment
was ascertained systematically from intraoperative records. An extension was
defined as any uterine wall defect, either
laterally into the uterine vasculature or
vertically into the cervix or contractile
uterus, that required additional surgical
steps to repair. Operators were asked not
to consider as an extension any irregularity in the wound edge that required anything more than the standard uterine
closure. Both the surgeon and assistant
should have been in agreement on the
presence of unintended extension; in
SEPTEMBER 2008 American Journal of Obstetrics & Gynecology
292.e2
SMFM Papers
cases of disagreement, a third team
member was consulted to come to agreement. Location and number of unintended extension were recorded, and notation was made if the tear involved the
bladder, the cervix, the broad ligaments,
or the uterine arteries. Uterine artery injury was defined as disruption of the vessels that required placement of a suture
to achieve adequate hemostasis. Blood
loss was estimated from the blood that
had been collected in the suction device,
in the plastic pouches of sterile drapes,
and in the saturation of pads and
sponges. Excessive bleeding during the
procedure was defined as estimated
blood loss of ⬎1500 mL. The need for
additional stitches to achieve adequate
hemostasis after the repair of the uterine
incision with a continuous suture was recorded. After delivery of the infant, oxytocin solution that had been prepared
with 20 IU/500 mL of saline solution was
infused over 30 minutes to prevent uterine atony. The need for additional uterotonic agents for the management of intraoperative uterine atony was recorded
systematically. On the first postoperative
day, the hemoglobin value was determined and compared with the admission
value. Less experienced operator was defined arbitrarily as an operator who had
performed ⬍100 cesarean deliveries.
The primary outcome measure was
the incidence of unintended extension.
Power calculation was based on a previous study in which the unintended extension rate was 12.4%.5 With ␣ ⫽ .05
and ␤ ⫽ 80%, data for 403 patients in
each arm were required to demonstrate a
difference of 6% between groups. Other
outcomes of interest included estimated
blood loss, blood loss of ⬎1500 mL,
change in hemoglobin value, rate of
uterine artery injuries, blood transfusion, and the need for additional suture
during or after closure of uterine
incision.
Statistical analysis was performed with
GraphPad Prism software (version 4.00;
(GraphPad Software, San Diego, CA)
and SPSS software (version 12.0; SPSS
Inc, Chicago, IL). The t-test and the
Mann Whitney U test were used to compare continuous parametric and nonparametric variables, respectively. Pro292.e3
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FIGURE 2
Flow of participants through each stage
of the randomized clinical trial
Assessed for eligibility
(n=818)
Excluded (n=7)
Enrollment
811 randomized
Allocated to transversal expansion
(n= 406)
Received allocated intervention
(n= 406)
Analyzed
(n=406)
•
•
Refused to participate (n= 4)
Emergency procedures on
admission (n=3)
Allocated to cephalad-caudad expansion
(n= 405)
Allocation
Analysis
Received allocated intervention
(n= 405)
Analyzed
(n= 405)
Cromi. Blunt expansion of the low transverse uterine incision at cesarean delivery. Am J Obstet Gynecol 2008.
portions were compared with the use of
the Fisher exact test. Parameters that
presented significant correlation or a
tendency towards association (P ⬍ .10)
with the outcomes of interest were entered into a logistic regression model to
select independent predictors. A probability value of ⬍.05 was considered to be
statistically significant.
R ESULTS
Of the 818 eligible women who underwent cesarean delivery during the study
interval, 4 women declined participation
in the study, and 3 women had emergency indications for cesarean delivery
on arrival at the triage unit (placenta abruptio, 2 women; hemorrhage from placenta previa, 1 woman) that prevented
adequate informed consent because of
time limitation. Of the 811 women who
agreed to participate, 406 women were
assigned to the transversal expansion
group, and 405 women were assigned to
the cephalad-caudad expansion group
(Figure 2). The women in the trial
groups were similar for baseline obstetric
and demographic characteristics (Table
American Journal of Obstetrics & Gynecology SEPTEMBER 2008
1). All patients underwent the allocated
technique for uterine incision expansion. No patient required either T or J
vertical extension of the incision into the
upper uterine segment or intended sharp
extension to further widen the uterine
opening that had been obtained by blunt
technique to allow delivery of the fetus.
None of the women in either group underwent cesarean hysterectomy. Table 2
displays the comparison of surgical outcomes between groups. Unintended extension occurred in 30 of 406 women
(7.3%) in the transverse group and in 15
of 405 women (3.7%) in the cephaladcaudad group. In consequence, more
women in the transverse group required
additional suture placement (33.2% vs
22.9%). Location of unintended extension was lateral in 28 of 30 women
(93.3%) in the transversal group and in
14 of 15 women (93.3%) in the cephaladcaudad group. Of the unintended lateral
extensions 16 of 28 women (57.1%) in
the transversal group and 9 of 14 women
(64.3%) in the cephalad-caudad group
were on the right side. Cervical lacerations
occurred in 2 (0.5%) and 1 (0.25%)
SMFM Papers
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TABLE 1
TABLE 3
Clinical characteristics of the study groups
32.7 ⫾ 4.8
32.6 ⫾ 4.9
.81
Univariate analysis of specific
risk factors for unintended
extension of the uterine incision
at caesarean delivery
351 (86.4%)
344 (84.9%)
.55
Variable
OR (95%CI)
Previous cesarean
delivery
0.7 (0.3, 1.5)
Transversal group
(n ⴝ 406)
Characteristic
a
Maternal age (y)
Cephalad-caudad group
(n ⴝ 405)
P value
..............................................................................................................................................................................................................................................
Nulliparous (n)
..............................................................................................................................................................................................................................................
2a
Body mass index (kg/m )
27.3 ⫾ 4.2
26.7 ⫾ 4.0
.06
Gestational age (wk)
38.5 ⫾ 2.6
38.3 ⫾ 2.4
.13
...........................................................................................................
Previous cesarean delivery (n)
90 (22.2%)
104 (25.7%)
.25
..................................................................................................
..............................................................................................................................................................................................................................................
a
..............................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Labor stage
Not in labor
1.3 (0.6, 2.6)
First stage
0.6 (0.2, 1.6)
Second stage
1.1 (0.5, 2.4)
..................................................................................................
Labor stage (n)
.....................................................................................................................................................................................................................................
Not in labor
296 (72.9%)
274 (67.6%)
.11
..................................................................................................
First stage
46 (11.3%)
64 (15.8%)
.06
...........................................................................................................
Second stage
64 (15.8%)
67 (16.5%)
.77
.....................................................................................................................................................................................................................................
.....................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Indication (n)
.....................................................................................................................................................................................................................................
Malpresentation
62 (15.3%)
57 (14.1%)
.69
Fetal distress
91 (22.4%)
87 (21.5%)
.80
Previous cesarean delivery
89 (21.9%)
101 (24.9%)
.32
Dystocia
87 (21.4%)
88 (21.7%)
.93
Other
77 (19.0%)
72 (17.8%)
.72
357 (87.9%)
365 (90.1%)
.37
.....................................................................................................................................................................................................................................
.....................................................................................................................................................................................................................................
.....................................................................................................................................................................................................................................
.....................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Regional anesthesia (n)
..............................................................................................................................................................................................................................................
a
Operating time (min)
38.9 ⫾ 11.9
40.4 ⫾ 11.8
.15
..............................................................................................................................................................................................................................................
Less experienced operator (n)
53 (13.0%)
48 (11.8%)
.67
Nonvertex fetal
presentation
0.7 (0.3, 1.8)
Transversal
expansion
2.0 (1.1, 3.8)
Emergency
procedure
1.1 (0.6, 1.9)
Less experienced
operator
0.9 (0.3, 1.9)
Macrosomic fetus
(⬎4000 g)
9.9 (4.7, 22.6)
...........................................................................................................
...........................................................................................................
...........................................................................................................
...........................................................................................................
Cromi. Blunt expansion of the low transverse uterine
incision at cesarean delivery. Am J Obstet Gynecol
2008.
..............................................................................................................................................................................................................................................
a
Birthweight (g)
3150 ⫾ 554
3112 ⫾ 588
.34
15 (3.7%)
17 (4.2%)
.72
..............................................................................................................................................................................................................................................
Macrosomia ⬎4000 g (n)
..............................................................................................................................................................................................................................................
a
Values are reported as mean ⫾ SD.
Cromi. Blunt expansion of the low transverse uterine incision at cesarean delivery. Am J Obstet Gynecol 2008.
women in the transversal group and in the
cephalad-caudad group, respectively.
Multiple logistic regression was used
to model the relationship between group
assignment and unintended extension of
uterine incision, after we controlled for
possible confounders. Table 3 shows the
results of univariate analysis of risk factors for unintended extensions. Both
transversal technique for uterine incision expansion and fetal macrosomia retained statistical significance when en-
TABLE 2
Comparison of surgical outcomes between groups
Outcome
Transversal group
(n ⴝ 406)
Unintended extension (n)
30 (7.4%)
Uterine vessels injury (n)
2 (0.5%)
Cephalad-caudad group
(n ⴝ 405)
P value
15 (3.7%)
.03
..............................................................................................................................................................................................................................................
0
.50
..............................................................................................................................................................................................................................................
Need for additional stitches (n)
135 (33.2%)
93 (22.9%)
.001
Estimated blood loss (mL)
440 ⫾ 341
398 ⫾ 242
.09
Blood loss ⬎1500 mL (n)
8 (2.0%)
1 (0.2%)
.04
Hemoglobin decrease (g/dL)
1.2 ⫾ 1.0
1.0 ⫾ 0.8
.05
Blood transfusion (n)
3 (0.7%)
3 (0.7%)
..............................................................................................................................................................................................................................................
a
..............................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
a
..............................................................................................................................................................................................................................................
1.0
..............................................................................................................................................................................................................................................
a
Values are reported as mean ⫾ SD.
Cromi. Blunt expansion of the low transverse uterine incision at cesarean delivery. Am J Obstet Gynecol 2008.
tered into the multivariable regression
model (odds ratio [OR], 2.2 [95% CI,
1.1, 4.2] and 10.6 [95% CI, 4.6, 24.5],
respectively).
We further analyzed the relationship
between blood loss of ⬎1500 mL at cesarean delivery and group assignment by
controlling for contributors to blood
loss at cesarean delivery. The results of
univariate analysis of potential risk factors for excessive blood loss (⬎1500 mL)
at caesarean delivery are displayed in Table 4. Transversal technique to expand
uterine incision and placenta previa as
indication to surgery remained predictors of blood loss of ⬎1500 mL when entered simultaneously into a logistic regression model (OR, 8.4 [95% CI, 1.03,
68.6] and 18.5 [95% CI, 4.2, 82.1], respectively). No difference was found
between groups in the proportion of patients who required additional uterotonic agents (17/406 vs 13/405; P ⫽ .58).
C OMMENT
Our results indicate that blunt expansion
of uterine incision by exerting a cephalad-caudad traction is associated with
SEPTEMBER 2008 American Journal of Obstetrics & Gynecology
292.e4
SMFM Papers
lower risks of unintended extension and
blood loss of ⬎1500 mL at cesarean delivery, compared with the transversal
technique.
Options to expand the uterine incision
at cesarean delivery have been evaluated
in 2 randomized trials that compared
sharp vs blunt extension.4,5 The first trial
involved 147 sharp vs 139 blunt uterine
incision expansions and found no difference in the rate of unintended extension
and postpartum hemoglobin levels.4
However, this study was underpowered
to find significant differences in this outcomes. A further study, which was published more recently and involved a total
of 945 women (470 women who underwent sharp uterine incision expansion
and 475 women who underwent blunt
expansion), demonstrated that sharp
technique was associated with increased
estimated blood loss, change in hematocrit level, incidence of postpartum hemorrhage, and risk of inadvertent extensions of the uterine incision, compared
with the blunt tecnique.5 Additional
postulated advantages of blunt expansion include both speed and less risk of
causing injury to the fetus.
When the uterine incision is widened,
extreme caution should be taken to make
the opening wide enough to allow delivery of the fetus, without tearing into the
uterine arteries and veins that course
through the lateral margins of the uterus.
A reported disadvantage of the conventional expansion from medial to lateral
by blunt technique is a higher likelihood
of extension of the uterine incision onto
the uterine vessels if the fingers of the operator are swept too far laterally.8,9 Indeed, by pulling apart the lateral ends of
the incision, the index fingers apply the
maximum traction force at each lateral
edge. Conversely, when pulling forces
are exerted vertically, the peak force
magnitude is applied along the midline.
Under these circumstances, the mechanical resistance to tissue dissection at the
lateral margins of the uterus provides a
force feed-back that constrains the operator’s fingers to make further movement
that can generate tissue damage. We believe that this force feed-back allowed a
widening of the uterine incision in a controlled fashion, even in the presence of a
292.e5
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very thin lower uterine segment. On the
other hand, when the lower uterine segment was not well-developed, additional
force to overcome excessive tissue resistance at the lateral ends could be
achieved by sequentially inserting the
third and sometimes fourth fingers of
each hand on the midline, while pulling
in a cephalad-caudad direction, to obtain an adequate opening.
Uterine incision extension with a
cephalad-caudad traction can decrease
the risk of excessive blood loss, both by
offering some degree of protection
against uncontrolled lateral extension
and by minimizing tissue damage, because expansion follows the path of least
tissue resistance. The lower proportion
of cases that require additional stitches
to achieve adequate hemostasis of the
uterine scar after closure of the uterus in
the cephalad-caudad expansion group
seems to support a less traumatic dissection of tissue planes. Moreover, transversal expansion by pulling in a vertical
direction can prevent the accumulation
of myometrium fibers at the ends of the
incision as a consequence of a conventional blunt extension that has been considered to increase the risk of sacculation-type defects in the uterine wall.10
We acknowledge the potential for bias in
determination of the presence or absence
of extension, given the subjective nature of
this assessment. We sought to use strict criteria to define unintended extension to
limit the possibility of biases that influence
the evaluation of treatment efficacy. An
additional potential drawback of this trial
was the use of unintended extension as primary outcome measure, assuming a correlation between this surrogate outcome and
maternal morbidity. Clinical judgment
and data from previously published studies suggest an association between unintended extension of uterine incision and
increased bleeding at cesarean delivery.
The higher proportion of women with a
blood loss of ⬎1500 mL in the transversal
expansion group and the difference between groups in hemoglobin drop after the
procedure approaches statistical significance, which suggests that unintended extension of uterine incision can translate ultimately in higher maternal morbidity.
The standardized surgical steps other than
American Journal of Obstetrics & Gynecology SEPTEMBER 2008
TABLE 4
Univariate analysis of risk factors
for excessive blood loss (>1500
mL) at caesarean delivery
Variable
Body mass index ⬎
30 kg/m2
OR (95%CI)
1.3 (0.3, 6.3)
...........................................................................................................
Twin gestation
1.3 (0.7, 22.2)
Previous cesarean
delivery
2.0 (0.5, 7.4)
...........................................................................................................
...........................................................................................................
Emergency procedure
1.2 (0.3, 4.4)
Cesarean delivery
during labor
8.2 (0.5, 141.1)
...........................................................................................................
...........................................................................................................
Placental abruption
4.9 (0.3, 91.6)
Pregnancy-induced
hypertension/
preeclampsia
3.3 (0.4, 27.5)
...........................................................................................................
...........................................................................................................
Placenta previa
17.7 (4.2, 75.4)
...........................................................................................................
Transversal expansion
8.1 (1.01, 65.2)
Macrosomic fetus
(⬎4000 g)
3.1 (0.4, 25.6)
...........................................................................................................
Cromi. Blunt expansion of the low transverse uterine
incision at cesarean delivery. Am J Obstet Gynecol
2008.
the technique of uterine incision extension
and the strict control for variables that are
associated potentially with increased blood
loss at cesarean delivery confer strength to
our results. Our study design did not allow
for the collection of information on postoperative complications but for intraoperative outcomes. We acknowledge that having information on postpartum febrile
morbidity and/or endometritis and pain
medication requirements would have
added to the completeness of this randomized comparison.
Cesarean delivery is 1 of the oldest surgical procedures in obstetrics and gynecology. Each practitioner develops several refinements of the technique that are
based mainly on individual experience
and expertise. However, it is important
to recognize that repetition and habit
should not prevent alteration of a technique after one has ascertained the best
approach systematically by integrating
clinical expertise with the available evidence from well-designed investigational trials. Our findings demonstrate
that blunt expansion of the uterine incision with a cephalad-caudad traction is
associated with less risk of unintended
SMFM Papers
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extension and blood loss of ⬎1500 mL
and should be preferred to the conventional expansion in a transversal fashion
when lower segment cesarean delivery is
performed. These data can serve as the basis for a larger study to confirm whether
this refinement of cesarean delivery technique confers tangible and worthwhile
benefits to the patients.
f
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