ORIGINAL RESEARCH
The Effect of Childbirth on Pelvic Organ Mobility
H. P. Dietz, MD (Heidelberg), FRANZCOG, and M. J. Bennett, MD (UCT), FRANZCOG
OBJECTIVE: To study the effect of child birth on pelvic organ
mobility in a prospective observational study.
METHODS: A total of 200 women were recruited early in
their first ongoing pregnancy and examined by translabial
ultrasound in the first/early second trimester, the late third
trimester, and 2–5 months postpartum. Peripartal changes
in the mobility of urethra, bladder, cervix, and rectal ampulla were correlated with labor and delivery data.
RESULTS: A total of 169 women returned postpartum
(84.5%). Highly significant increases in organ mobility on
Valsalva were found after vaginal delivery (P < .001), with
forceps causing the most marked changes. Length of second stage, especially active second stage, correlated with an
increase in pelvic organ descent (P ⴝ .03 to P < .001). The
influence of gestational age, length of first stage, and birth
weight did not reach significance.
CONCLUSION: Vaginal birth, in particular operative delivery, negatively affects pelvic organ support. This appears to
be true for all three vaginal compartments. All forms of
cesarean delivery were associated with relatively less pelvic
organ descent. These findings may partly explain the protective effect of elective cesarean delivery for future symptoms of pelvic floor disorders. (Obstet Gynecol 2003;102:
223– 8. © 2003 by The American College of Obstetricians
and Gynecologists.)
The etiology of genuine stress incontinence and female
pelvic organ prolapse is thought to be multifactorial.1
Traumatic damage to fascial and/or muscular support
structures during vaginal childbirth may be an important
contributor to the development of stress incontinence
and prolapse, with congenital, hormonal, and other factors also contributing.2
There is increasing evidence to support the concept of
permanent pelvic floor damage after childbirth. So far,
this evidence is mainly based on neurophysiologic studies implying pudendal nerve damage.3 However, the
value of pudendal nerve neurophysiology is by no
From the School of Women’s and Childrens’ Health, University of New South
Wales, Randwick; and Royal Hospital for Women, Sydney, Australia.
HPD was supported by a Research Fellowship of the Royal Australian and New
Zealand College of Obstetricians and Gynecologists funded by Mayne Nickless Ltd
for the duration of this study.
means undisputed,4 and reinnervation is the rule rather
than the exception. More convincing evidence is available for anal sphincter trauma.5
As regards damage to fascial structures, it has frequently been assumed that at least some of the distinct
fascial defects seen in later life, such as paravaginal
defects,6 can be attributed to delivery-related trauma.
With the more widespread use of translabial ultrasound,
it has recently become possible to investigate the effects
of vaginal delivery on the supports of the anterior vaginal wall and bladder neck.7–10 Results to date have been
inconclusive and conflicting, probably because of methodologic difficulties and a lack of numbers. In this prospective observational study, the authors attempted to
define the extent of trauma to pelvic support structures
by measuring pelvic organ descent on maximal Valsalva
maneuver before and after delivery in a cohort of nulliparous women.
MATERIALS AND METHODS
A total of 200 nulliparous women were recruited in the
antenatal clinic of a large tertiary hospital. They were
seen three times—at 6 –18 weeks’ gestation, at 32–37
weeks’ gestation, and for the third and last visit at 2–5
months postpartum. Appointments consisted of an interview, paper towel test, flowmetry, and translabial ultrasound. For the purposes of this study, third-trimester
and postpartal ultrasound data as well as labor and
delivery data were analyzed to determine the influence of
childbirth on pelvic organ mobility.
An assessment of the mobility of urethra, bladder,
cervix, and rectal ampulla was performed by translabial
ultrasound, with the patient supine and after voiding.
Detailed descriptions of the methodology11,12 have recently been published. Both rotation of the proximal
urethra and bladder neck descent have been shown to be
strongly associated with genuine stress incontinence in
urogynecologic patients.13 The following ultrasound
systems were used for B-mode imaging with 3.5–7-MHz
curved array transducers: Toshiba EccoCee (Toshiba
Australia, North Ryde, NSW, Australia), ATL HDI
3000 (Philips Medical Systems Australasia, Sydney,
NSW, Australia), Hitachi EUB 240 (Hitachi Australia,
VOL. 102, NO. 2, AUGUST 2003
© 2003 by The American College of Obstetricians and Gynecologists. Published by Elsevier.
0029-7844/03/$30.00
doi:10.1016/S0029-7844(03)00476-9
223
Table 1. Explanation of the Parameters Used to Describe
Pelvic Organ Position and Descent on Transperineal Ultrasound
Rotation
Rotation of proximal urethra on Valsalva
(in degrees)
BND
BND (vertical) on Valsalva (in mm)
Cystocele descent Maximal caudal displacement of the
posterior bladder wall on Valsalva (in
mm), relative to inferior margin of
symphysis pubis
Cervical descent Maximal caudal displacement of the
cervix uteri on Valsalva (in mm),
relative to inferior margin of symphysis
pubis
Rectal descent
Maximal caudal displacement of the
rectal ampulla on Valsalva (in mm),
relative to inferior margin of symphysis
pubis
BND ⫽ bladder neck descent.
Figure 1. Field of view of translabial ultrasound (midsagittal orientation).
Dietz. The Effect of Childbirth. Obstet Gynecol 2003.
North Ryde, NSW, Australia), and Dornier AI 5200
(Meditron, Ringwood, Vic., Australia). Because electronic calipers are standardized for reproducibility according to industry-wide standards, measurements are
generally regarded as comparable between transducers
and systems.14 Translabial imaging was performed by
covering the transducer with a glove and placing it in a
midsagittal orientation on the perineum. The resulting
view is shown in Figure 1, with Figure 2 illustrating a
case of markedly increased pelvic organ mobility after
vaginal delivery. Measurements were performed on
screen or on printouts. The inferoposterior margin of the
symphysis pubis was used as a fixed point of reference.
Differences between measurements at rest and on Valsalva was recorded as proximal urethral rotation in
degrees and bladder neck descent in millimeters. The
maximal descent (⫽ degree of prolapse) reached by
bladder (ie, a cystocele if one is present), cervix, and
rectal ampulla (or, if present, a rectocele) on Valsalva
was recorded as a positive figure (in millimeters) if the
leading edge of the organ remained above the inferoposterior margin of the symphysis, and as negative if below.
For a description of the ultrasound parameters used, see
Table 1.
At least three Valsalva maneuvers were performed,
with the one producing the most marked descent used
for numerical evaluation. This assessment was repeated
in the same fashion at the postpartum appointment at
which time the assessor was blinded to all delivery data,
Figure 2. Antepartum (left) and postpartum (right) maximal Valsalva maneuvers as imaged by translabial ultrasound. There
is a marked increase in pelvic organ mobility in this primiparous woman. The clinical equivalent of postpartum findings are
a first-degree cystourethrocele and a first-degree rectocele with significant perineal relaxation.
Dietz. The Effect of Childbirth. Obstet Gynecol 2003.
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Table 2. Descriptive Statistics for Ultrasound Parameters Used to Define Pelvic Organ Mobility at 32–38 Weeks’ Gestation
(n ⫽ 173)
Mean
Maximum
Minimum
SD
Urethral rotation
(degrees)
BND
(mm)
Cystocele descent
(mm above SP)
Cervical descent
(mm above SP)
Rectal descent
(mm above SP)
44
100
10
25.6
22.2
43.8
1
10.3
7
43
⫺22.5
11.5
36.8
72
⫺10.7
14.5
16.5
60
⫺35.6
20.9
BND ⫽ bladder neck descent; SP ⫽ symphysis pubis; SD ⫽ standard deviation.
Negative values infer descent below the symphysis pubis on Valsalva. The cervix could be seen in 172 cases, the rectal ampulla in 164.
with the patient’s abdomen covered by a sheet. Women
were asked not to divulge any information regarding
their delivery until after the scan.
Interobserver variability for the main outcome parameter bladder neck descent (in millimeters) was recently
determined by the authors as a coefficient of variation of
0.08 and an intraclass correlation coefficient (2,1) of .98
for evaluation of the same Valsalva maneuver by different examiners. A coefficient of variation of 0.20 or an
intraclass correlation coefficient (2,1) of .79 were determined for evaluation of different Valsalva maneuvers by
two blinded examiners (unpublished data). Labor and
delivery details were gathered through data collection
sheets attached to the patient’s antenatal record and
checked or completed through access to hospital notes
and the institutional obstetric database. Total duration of
the second stage of labor was defined as the interval
between confirmation of full cervical dilatation and delivery of the infant. Active second stage was taken as the
time between commencement of active pushing and
delivery. Passive second stage was defined as the difference between total and active second stage. Ethics Committee approval had been obtained from the local Ethics
Committee (SESAHS EC approval 99/184).
Sample size calculations were based on a pilot study
performed under the supervision of the first author
(unpublished data). In this pilot data, the group-specific
means and standard deviations (SD) were 15.5 mm (SD
10.3) for normal vaginal delivery, 13.5 mm (SD 10.6) for
cesarean delivery, and 25 mm (SD 9.6) for vaginal
operative delivery. Assuming a dropout rate of 33% and
proportions of 21% cesarean delivery, 15% vaginal operative deliveries, and 64% normal vaginal deliveries
(data for Royal Hospital for Women, 1998), a sample
size of 200 recruits was estimated to provide over 95%
power to detect a statistically significant difference between normal vaginal delivery versus forceps/vacuum as
well as cesarean delivery versus forceps/vacuum as regards bladder neck descent (␣ ⫽ .05). All data except
length of second stage were normally distributed as
assessed by Kolmogorov–Smirnov testing. The t test
statistics were used for continuous, normally distributed
parameters. Spearman correlation coefficient statistics
were used to correlate length of second stage with ultrasound data. Analysis of variance followed by Tukey
multiple comparisons were employed to test the outcome of delivery mode against explanatory parameters.
A P ⬍ .05 was taken as indicating significance.
RESULTS
Of the originally recruited 200 women, 173 were seen for
an assessment at 32–38 weeks’ gestation. Table 2 shows
descriptive statistics for the ultrasound parameters used.
Cervix and rectum were not clearly seen in one and nine
cases, respectively. Delivery information was available
for all 173 women. Ninety-nine were delivered by normal vaginal delivery (57%), nine underwent elective or
prelabor cesarean delivery (5%), and 36 had an intrapartum cesarean delivery (21%). Indications for cesarean
delivery were failure to progress in first stage (n ⫽ 18),
failure to progress in second stage (n ⫽ 8), fetal distress (n
⫽ 7), breech presentation (n ⫽ 5), failed induction (n ⫽
4), brow presentation, placenta previa, and back pain (n
⫽ 1 each).
Twenty-nine women (17%) underwent vaginal operative deliveries, of which ten were forceps deliveries
(6%), and the remainder vacuum extractions. Gesta-
Table 3. Demographic Data for Attenders and Women Who Did Not Attend All Three Visits
Age (y) [mean (SD)]
Gestation at recruitment (wk) [mean (SD)]
BMI (kg/m2) [mean (SD)]
Previous pregnancies (⬍20 wk) median (range)
Attenders (n ⫽ 169)
Nonattenders (n ⫽ 31)
P
29.6 (5.3)
12.7 (1.8)
23.6 (3.9)
1 (1–6)
26.8 (4.6)
12.8 (2.2)
24.1 (4.7)
2 (1–7)
.002
NS
NS
NS
SD ⫽ standard deviation; BMI ⫽ body mass index; NS ⫽ not significant.
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Table 4. Descriptive Statistics for Ultrasound Parameters Used to Define Pelvic Organ Mobility at Approximately 3 Months
Postpartum (n ⫽ 169)
Urethral rotation
(degrees)
BND
(mm)
Cystocele descent
(mm above SP)
Cervical descent
(mm above SP)
Rectal descent
(mm above SP)
61.3
120
0
34.4
28.5
50
5.8
10.6
0.1
29
⫺23.1
12.3
20.8
51
⫺15
15.9
2.9
43
⫺33.1
19
Mean
Maximum
Minimum
SD
Abbreviations as in Table 2.
Negative values infer descent below the symphysis pubis on Valsalva. Cervix and rectum could only be seen in 163 cases each.
tional age at delivery was a mean of 278 (198 –301) days,
the length of first stage was a mean of 492 (0 –1263)
minutes, passive second stage 26 (0 –270) minutes, and
active second stage 53 (0 –255) minutes. The birth
weight was 3471 (930 –5160) g on average.
One hundred sixty-nine women attended a visit 2–5
months postpartum at which time an identical assessment was performed. Eight of those 169 had missed the
previous appointment. Table 3 lists demographic data
for attenders and nonattenders. Of 31 nonattenders, 12
had moved, ten were unwilling to continue, four had
miscarried, two had had a termination of pregnancy, and
three were lost to follow-up. Nonattenders were significantly younger but did not differ for other demographic
parameters. The average enrollment period (time interval between first and last appointment) was on average
282 days (209 – 417) days. On ultrasound imaging, cervix and/or rectum were not reliably imaged in six cases
each. Table 4 shows descriptive statistics for pelvic organ
mobility at the postpartum visit.
Between the second and third visit, all parameters
underwent significant change when tested by two-sample t test (Table 5). In all cases, this shift was towards
increasing mobility. These peripartum changes were correlated with all labor/delivery-related factors that could
be assumed to contribute. There were no significant
correlations between length of gestation and length of
first stage on the one hand and indices of pelvic organ
mobility or the increase in the values of those indices
peripartum on the other hand. Birth weight showed
consistent trends towards higher increases in mobility
with higher weights although these did not reach signif-
icance. No significant differences were detected beween
spontaneous and nonspontaneous onset of labor.
All tested parameters of pelvic organ mobility change
correlated weakly but positively with the length of the
second stage of labor. Table 6 gives the significance of
correlations between total length of second stage and
passive/active second stage on the one hand, and ultrasound parameters on the other hand.
Analysis of variance was carried out after stratification
for delivery mode. A total of 161 datasets were available
for direct comparison. As regards the main outcome
parameter used to define anterior vaginal wall support
(ie, bladder neck descent on Valsalva maneuver), delivery mode proved to be a strong determinant of peripartum change. Elective or prelabor cesarean delivery led to
an average reduction in bladder neck descent of 2.27
mm. Bladder neck descent increased postpartum for
every other delivery mode, in the order of cesarean
delivery during first stage, cesarean delivery in second
stage, normal vaginal delivery, and ventouse and forceps
deliveries (Table 7) (P ⫽ .003 for analysis of variance).
The same pattern was observed for all other parameters
of pelvic organ descent (analysis of variance for urethral
rotation, n ⫽ 161, P ⫽ .001; analysis of variance for
cystocele descent, n ⫽ 161, P ⫽ .001; analysis of variance
for cervical descent, n ⫽ 157, P ⫽ .019; and analysis of
variance for rectal descent, n ⫽ 153, P ⫽ .002).
Using Tukey multiple comparison after analysis of
variance for bladder neck descent, significant differences
remained regarding the pairwise comparisons of prelabor cesarean delivery versus normal vaginal delivery,
prelabor cesarean delivery versus forceps, and cesarean
Table 5. Comparison of Ultrasound Data Ante- and Postpartum
Parameter
Urethral rotation
(degrees)
BND
(mm)
Cystocele descent
(mm above SP)
Cervical descent
(mm above SP)
Rectal descent
(mm above SP)
Antepartum
Postpartum
P
44
61.3
⬍.001
22.2
28.5
⬍.001
7
0.1
⬍.001
36.8
20.8
⬍.001
16.5
2.9
⬍.001
Abbreviations as in Table 2.
For sample numbers, standard deviation, and ranges, see Tables 2 and 4. In all instances significant associations show increased pelvic organ
descent postpartum (higher numbers for the first three parameters, lower numbers for the last two). Two-sample t test.
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OBSTETRICS & GYNECOLOGY
Table 6. P Values for Correlations Between Parameters of Pelvic Organ Descent and Total, Passive, and Active Second
Stage (n ⫽ 161 for First Three Parameters, n ⫽ 157 for Cervical, and n ⫽ 153 for Rectal Descent)
Change in
parameters
Urethral
rotation
BND
Cystocele
descent
Cervical
descent
Rectal
descent
Total second stage
r (P )
Passive second stage
r (P )
Active second stage
r (P )
0.192
(.016)
0.131
(.10)
0.180
(.024)
0.171
(.031)
0.121
(.128)
0.170
(.032)
⫺0.232
(.003)
⫺0.18
(.024)
⫺0.231
(.003)
⫺0.211
(.009)
⫺0.144
(.077)
⫺0.176
(.029)
⫺0.288
(⬍.001)
⫺0.19
(.019)
⫺0.223
(.005)
BND ⫽ bladder neck descent.
All relationships are positive in the sense that increased length of second stage was associated with increasing pelvic organ hypermobility/descent
on Valsalva. Spearman’s correlation statistics.
delivery in first stage versus forceps delivery. No significant associations were documented between symptoms
of bladder dysfunction such as stress and urge incontinence, frequency, nocturia and symptoms of voiding
difficulty, and ultrasound parameters of bladder neck
mobility.
DISCUSSION
There is increasing evidence for the concept of permanent pelvic floor damage after childbirth.15 Epidemiologic studies consistently show associations between parity on the one hand and stress incontinence or female
pelvic organ prolapse on the other hand.16,17 Direct
clinical evidence to date is mainly based on neurophysiologic studies implying pudendal nerve damage3 and
imaging data on anal sphincter trauma.5 Several papers
have been published investigating the effect of childbirth
on bladder neck mobility relative to the symphysis pubis,
assumed to be a measure of integrity of anterior compartment fascial structures. However, results to date have
been inconclusive.
Meyer et al,9 in a prospective study on approximately
150 nulliparous women, showed that bladder neck mobility was significantly increased after all vaginal deliveries with no differences between forceps and normal
vaginal delivery. However, low measurements for bladder neck descent (means of 10 –13 mm) raise doubts
regarding the methodology of this study. Bader et al7
found significant differences both between cesarean delivery and vaginal delivery and between normal and
operative vaginal delivery with regard to mobility of the
bladder neck, although this paper only reported postpartum imaging. Another small study also confirmed the
finding of increased mobility of the bladder neck after
vaginal childbirth.8
King and Freeman10 found no association between
delivery mode and changes in ultrasound measurements. An explanation for this may be found in the
methodology of this study: Patients were examined with
a full bladder, upright and in stirrups, with a Valsalva
force standardized at 30 mm Hg or 40 cm H2O with the
help of a spirometric device. All these factors would
minimize hypermobility18,19 and therefore the ability of
the study to detect the effect of delivery-related variables.
None of the mentioned studies investigated the central
or posterior compartments, which is straightforward and
requires no methodologic modifications.12 Central compartment prolapse is measured by demonstrating descent of the leading edge of the cervix on Valsalva. This
is easier in pregnancy because the cervix is enlarged and
more structured, showing a layered appearance. The
posterior compartment can be assessed sonographically
by demonstrating descent of the rectal ampulla. A rectocele results in ampullary contents developing in a ven-
Table 7. Change in Bladder Neck Descent (in mm) After Different Modes of Delivery (n ⫽ 161)
Delivery mode
n
Mean
SD
Prelabor cesarean
Cesarean delivery in stage I
Cesarean delivery in stage II
Normal vaginal delivery
Vacuum delivery
Forceps delivery
11
23
7
95
16
9
⫺2.27
2.63
4.00
7.24
9.22
14.49
8.75
9.50
4.58
10.17
14.72
6.53
–⫹– – – – – – – – –⫹– – – – – – – – –⫹– – – – –
(– – – – – – ⴱ– – – – – – – )
(– – – – ⴱ– – – – – )
(– – – – – – – – – ⴱ– – – – – – – – – )
(– – ⴱ– – )
(– – – – – – ⴱ– – – – – )
(– – – – – – – ⴱ– – – – – – – – )
– ⫹– – – – – – – – – ⫹– – – – – – – – – ⫹– – – – – – – – – ⫹– – – – –
⫺8.0
0.0
8.0
16.0
SD ⫽ standard deviation.
Most marked increase in descent is reflected in the most positive means. One-way ANOVA (analysis of variance) is significant at P ⫽ .003.
Asterisks represent means, dashed lines and brackets the 95% confidence intervals.
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Dietz and Bennett
The Effect of Childbirth
227
trocaudal direction. The correlation between clinical assessment, the recently developed prolapse quantification
system of the International Continence Society, and
ultrasound quantification is not as close as for the other
two compartments.12 Nevertheless, imaging is likely to
provide better quantitative information than either the
prolapse quantification system of the International Continence Society or clinical staging because the actual
position of organs rather than the surface topography of
the vagina is assessed.20
The authors believe that the study presented here goes
a long way towards furnishing proof for the hypothesis
that vaginal childbirth negatively affects the support
tissues of pelvic organs. Vaginal delivery resulted in
highly significant changes to the mobility of urethra,
bladder neck, posterior bladder wall, cervix, and rectal
ampulla/anterior rectal wall. These changes correlated
with length of second stage and with delivery mode.
All forms of cesarean delivery, but especially prelabor
cesarean, were associated with relatively less pelvic organ descent, with postpartum measurements in women
after prelabor cesarean delivery practically returning to
early pregnancy values. These findings may partly explain the protective effect of elective cesarean delivery
for future symptoms of pelvic floor disorders. However,
only randomized controlled intervention trials will provide definite proof of any such effect.
Changes in organ mobility imply alterations in the
biomechanical properties of support structures. These
may be attributed to stretching or disruption of fascial
and/or muscular tissues, and the study presented here
does not allow conclusions regarding the exact nature of
these changes. It is also unclear as to whether such
alterations are associated with symptoms in the long
term, and whether pregnancy itself causes (permanent or
transitory) biomechanical changes predating the delivery. Further work will be necessary to elucidate these
issues.
REFERENCES
1. Wilson PD, Herbison RM, Herbison GP. Obstetric practice and the prevalence of urinary incontinence three
months after delivery. Br J Obstet Gynaecol 1996;103:
154–61.
2. Swift SE, Pound T, Dias JK. Case-control study of etiologic factors in the development of severe pelvic organ
prolapse. Int Urogynecol J 2001;12:187–92.
3. Jozwik M, Jozwik M. Partial denervation of the pelvic floor
during term vaginal delivery. Int Urogynecol J 2001;12:
81–2.
4. Vodusek DB. Clinical neurophysiological tests in urogynecology. Int Urogynecol J 2000;11:333–5.
228
Dietz and Bennett
The Effect of Childbirth
5. Sultan AH, Monga AK, Stanton SL. The pelvic floor
sequelae of childbirth. Br J Hosp Med 1996;55:575–9.
6. Richardson AC, Lyon JB, Williams NL. A new look at
pelvic relaxation. Am J Obstet Gynecol 1976;126:568–73.
7. Bader W, Kauffels W, Degenhardt F, Schneider J. Postpartum ultrasound morphology of the pelvic floor [in German]. Geburtshilfe Frauenheilkd 1995;55:716–20.
8. Peschers U, Schaer G, Anthuber C, DeLancey JO,
Schuessler B. Changes in vesical neck mobility following
vaginal delivery. Obstet Gynecol 1996;88:1001–6.
9. Meyer S, Schreyer A, De Grandi P, Hohlfeld P. The effects
of birth on urinary continence mechanisms and other
pelvic-floor characteristics. Obstet Gynecol 1998;92:
613–8.
10. King JK, Freeman RM. Is antenatal bladder neck mobility
a risk factor for postpartum stress incontinence? Br J
Obstet Gynaecol 1998;105:1300–7.
11. Dietz HP, Wilson PD. Anatomical assessment of the bladder outlet and proximal urethra using ultrasound and
videocystourethrography. Int Urogynecol J 1998;9:365–9.
12. Dietz HP, Broome J, Haylen BT. Ultrasound quantification of uterovaginal prolapse. Ultrasound Obstet Gynecol
2001;18:511–4.
13. Dietz HP, Clarke B, Herbison P. Bladder neck mobility
and urethral closure pressure as predictors of genuine
stress incontinence. Int Urogynecol J 2002;13:289–93.
14. Kremkau FW. Diagnostic ultrasound: Principles and
instruments. Philadelphia: Saunders, 1998.
15. Davila GW. Informed consent for obstetrics management:
A urogynecologic perspective. Int Urogynecol J 2001;2:
289.
16. Mant J, Painter R, Vessey M. Epidemiology of genital
prolapse: Observations from the Oxford Family Planning
Association Study. Br J Obstet Gynaecol 1997;104:579–5.
17. Olsen AL, Smith VJ, Bergstrom JO, Colling JC, Clark AL.
Epidemiology of surgically managed pelvic organ prolapse
and urinary incontinence. Obstet Gynecol 1997;89:501–6.
18. Dietz HP, Wilson PD. The influence of bladder volume on
the position and mobility of the urethrovesical junction. Int
Urogynecol J 1999;10:3–6.
19. Dietz HP, Clarke B. The influence of posture on perineal
ultrasound imaging parameters. Int Urogynecol J 2001;12:
104–6.
20. Kenton K, Shott S, Brubaker L. Vaginal topography does
not correlate well with visceral position in women with
pelvic organ prolapse. Int Urogynecol J 1997;8:336–9.
Address reprint requests to: H. P. Dietz, MD, FRANZCOG,
DDU, 1/68 Brook Street, Coogee 2034 NSW, Australia; Email: [email protected].
Received October 22, 2002. Received in revised form February 12,
2003. Accepted March 13, 2003.
OBSTETRICS & GYNECOLOGY