To compare the clinical efficacies of inferior hypogastric
plexus blockade and acupuncture in the management of
idiopathic chronic pelvic pain (CPP).
The study included 117 patients with CPP. Group 1 in
cluded 62 patients who underwent inferior hypogastric
plexus blockade and group 2 included 55 patients who
underwent acupuncture. Pain level was assessed using a
visual analogue scale (VAS) immediately and at 2, 6, and
12 weeks after treatment.
The preprocedure VAS score was 7.6 ± 0.15 in group 1
and 7.7 ± 0.24 in group 2 (p > 0.05). Pelvic pain de
creased significantly in both groups after treatment,
with pretreatment and posttreatment scores of 7.6 ± 0.15
and 2.2 ± 0.88, respectively, in group 1 (p < 0.0001)
and 7.7 ± 0.24 and 4.7 ± 0.11, respectively, in
group 2 (p < 0.0001). However, the decrease in pain
scores throughout the clinical follow.up was significantly
more in group 1 than in group 2 (p< 0.0001). Complete
disappearance of symptoms was achieved in 72.6% of
patients in group 1 compared to 54.5% of patients in
group 2 (p = 0.3737). Patients who did not benefit from the treatment were significantly more in
group 2 than in group 1 (25.5% vs. 6.5%, p = 0.0294). No complications were reported in both
The study results showed that inferior hypogastric blockade had a 72.6% success rate and showed
a significantly higher effect on reducing pain intensity in a short period of time in the management
of CPP, compared to acupuncture.

Biomed J 2015;38:317-322)

Pelvic pain is a common gynecological complaint among
females of reproductive age. The intensity of pain may
vary from mildly irritating to incapacitating.[1] Chronic pelvic
pain (CPP) is commonly defined as noncyclic pain of at
least 6 months duration, localized to the pelvis or anterior
abdominal wall, or at or below the umbilicus and at lower back and buttocks.[2] CPP is the second most common gynecological
presenting complaint, accounting for 13–20% of
gynecological consultations and up to 25% of the indications
for diagnostic laparoscopy.[3] Many etiological factors can
contribute to CPP. More than one etiological factor may be
found in one patient, and both organic and non‑organic causes
may be present.[4] CPP is a problem requiring careful gynecological
evaluation to exclude gastrointestinal, orthopedic,
urological, neurological, and psychological involvement.[5]
CPP with no specific pathological finding is suggested to
be due to unrecognized dysfunction of the nervous system,
which is often difficult to treat. Medication and surgical intervention
may only provide temporary relief.[4] Nonsteroidal
anti‑inflammatory drugs are used as initial therapy for the
treatment of mild pain. They can also be used in combination
with opioids and adjuvant analgesics if the intensity of pain
worsens.[6] In most cases, good results from acupuncture
are achieved by adjunct treatments such as hypnosis, exercise,
and transcutaneous electrical stimulation; biofeedback
treatment with intensive psychotherapy has been shown to
achieve 71% pain reduction.[7,8] Visceral pain is transmitted
via the sympathetic nervous system, regardless of its etiology.
Sympathetic nerve blockade was reported to be an effective
method for the treatment of pelvic pain. While successful
results have been reported with superior hypogastric plexus
blockade through an anterior approach, the technique is associated
with injury to structures overlying the plexus, such
as the bowel, bladder, and common iliac artery. Studies have
revealed that acupuncture clinical trials have many problems,
including the use of unscientific research protocols and repeated
trials of acupuncture, but still papers related to this
procedure are increasingly being published in the literature.[9]
Meanwhile, inferior hypogastric plexus blockade was proved
to be safe and effective if properly performed, but clinical
trials of this procedure are scant.[10] The aim of the present
study was to compare the efficacy and safety of inferior
hypogastric plexus blockade with those of acupuncture for
the treatment of idiopathic CPP.
This study was conducted in the Department of Obstetrics
and Gynecology and the Pain Clinic of the Department
of Anesthesiology and Algesiology, Sohag University Hospital
during the period from February 2008 to January 2012.
The study protocol was approved by the faculty of
the ethical committee, and informed written consent was
obtained from each participating woman.
Women who met the inclusion criteria for CPP underwent
thorough history, general and pelvic examinations,
and abdominal and transvaginal ultrasonography. Routine
investigations were performed. Laparoscopy was performed
to exclude organic lesion. Patients were selected according roscopic guidance through the dorsal sacral foramen toward
the medial interior edge of the ventral sacral foramen until
contact was made with the medial bony edge of the ventral
sacral foramen. If sacral paresthesia was encountered, the
needle was retracted and rotated slightly to move past the
sacral nerve root. Small, incremental doses (0.1–0.3 ml) of
1% lidocaine during needle advancement improved patient
comfort without creating blockade of sacral nerve roots.
The needle was maneuvered along the medial edge of the
ventral sacral foramen to exit the ventral foramen as medial
as possible and anteromedially advanced for another
millimeter toward the midline presacral plane. Then, the
contrast medium was injected. If the needle is in the optimal
position, the contrast should spread cephalad and caudal
along the presacral plane conforming to the midline ventral
surface of the sacrum. A mixture of 10 ml of 2% lidocaine
and 10 mg of triamcinolone was injected only when proper
needle tip position was assured. If the injected contrast
medium and medication spread across the midline from the
side of the needle placement, then a unilateral block may
be adequate. However, contrast spread is more commonly
primarily unilateral, necessitating a bilateral needle placement
for complete blockade of the right and left inferior
hypogastric plexuses.
Description of the acupuncture technique
An ES‑130 Electro‑Acupuncture Device (Murakami,
Japan) was used for the acupuncture technique. Acupuncture
was performed using disposable stainless steel
needles (0.3 mm diameter, 60 mm length; Seirin Kasei,
Shimizu, Japan) by trained doctors.[8] The acupuncture protocol
consisted of a standardized set of acupuncture points
applied for 30 min twice weekly for 6 weeks with electrical
stimulation, based on zàng organs stipulated by Traditional
Chinese Medicine and meridian theory, as were described by
previous researchers.[6,11] First, needling was performed in the
auricular points, followed by the full‑body points. The body
acupuncture points selected at each visit included SJ5‑wai
guan, GB41‑zulin qi, LR3‑tai chang, LI 4‑he gu, SP 8‑di ji,
and SP 6‑san yin jiao. Needling was performed at a depth of
1.5–2.5 inch at each selected point, followed by the full‑body
points, until a deqi sensation was obtained.[12] Deqi is defined
as a feeling of soreness, numbness, distension, or heaviness
around the point after the needle was inserted; meanwhile,
the practitioner may feel tension around the needle.[13] The
needle remained in situ for 25–30 min; during this time,
the needle was stimulated with electrical stimulation using
low‑intensity pulsed currents administered at high frequencies
[between 10 and 200 pulses per second (pps)] at the
site of pain, and at high intensity and low frequency (lower
than 10 pps, usually 2 pps) in the trigger points.[14] The body
acupuncture points selected at each visit included SJ5‑wai guan, GB41‑zulin qi, LR3‑tai chang, LI 4‑he gu, SP 8‑di ji,
and SP 6‑san yin jiao. VAS scores (1 = no pain, 2–3 = mild
pain, 4–7 = moderate pain, 8–10 = severe disabling pain)
were used to assess the severity of pain before the start of
treatment and at 2, 4, and 12 weeks after treatment.[14] The
pain was also assessed 4 and 12 weeks after discontinuation
of treatment in both groups.
Sample size and statistical analysis
Using an online open epidemiological calculator (http://
for sample size estimation for the difference in the
mean,[15] the sample sizing assumed the expected difference
in the two mean values of VAS after the procedure in the
two arms of the study. The expected mean (SD) of the VAS
was presumed to be 5.0 (0.8) and 4.6 (0.7) following the
inferior plexus group and acupuncture procedure, respectively.
To achieve 80% power to detect this difference with a
significance level of 5%, it was estimated that 57 subjects per
group would be required. With a withdrawal/non‑evaluable
subject rate of 10%, a total of 64 subjects per group should be
recruited for the required total sample size of 128 subjects.
The Statistical Package for Social Sciences (SPSS
15 for Windows) was used for data recording and statistical
analysis. A Chi‑square test was used to compare the
qualitative data, and the Student t‑test was used to compare
the means of quantitative data. The Fisher’s exact test was
used when the cell count was less than 5. A p < 0.05 was
considered statistically significant.
The socio‑demographic characteristics of the two
groups are shown in Table 1. No significant differences
were found between the two groups with regard to their
age, parities, occupations, and body mass indices (p > 0.05).
Both groups had a similar duration of CPP (10.3 ± 6.3 vs.
11.6 ± 3.4 months, p > 0.05).
CPP commonly presented as a dull ache (58.06% in
group 1 vs. 61.8% in group 2) and involved the whole pelvis (50% in group 1 and 50.9% in group 2), with
no statistically significant differences between the two
groups (p = 0.9555 and p = 0.9551, respectively).
The pain was localized in most of the cases (69.35%
in group 1 and 61.8% in group 2) and confined to the lower
back in 25.8% of the subjects in group 1 and 25.4% of the
subjects in group 2. However, no statistically significant
difference in pain characteristics was observed between the
two groups [Table 2].
The VAS score before intervention was 7.6 ± 0.15
in group 1 compared to 7.7 ± 0.24 in group 2, with no
statistically significant difference (p > 0.05). Although
both groups had statistically significant reduction in pain
levels throughout the follow‑up period, group 1 reported a
more significant reduction in pain level when compared to
group 2 (p < 0.05) [Table 3].
The results evaluated after 4 and 12 weeks of the interventions
are presented in Table 4. After 1 month of treatment,
group 1 reported a higher frequency of complete pain relief
than that reported by group 2 (61.2% vs. 40.09%), although
the difference between the groups was not significant
(p = 0.2487). After 3 months, complete disappearance of
symptoms was reported by 72.5% of the patients in group 1
and 54.5% of the patients in group 2 (p = 0.420). The number
of patients who reported that there was no change in the level
of pain after 1 and 3 months of intervention was significantly
higher in group 2 than in group 1 (9.6% vs. 30.9%, p = 0.033
and 25.5% vs. 6.5%, p = 0.0294, respectively). The number
of patients who did not benefit from the treatment was
significantly higher in group 2 than in group 1 (25.5% vs.
6.5%, p = 0.0294). No complications were reported in both
groups during the intervention and the follow‑up period.
CPP is a common complaint among women and is a
major public health concern worldwide.[16] It causes frustration
among patients, which often has a major impact on
quality of life.[13] Despite the high prevalence of CPP, its
management remains a major challenge to clinicians mainly
because of the lack of understanding of its natural history,
etiology, and pathogenesis.
In the present study, we compared the efficacy and
safety between inferior hypogastric plexus blockade and
acupuncture as a nonconventional therapeutic modality
for the management of chronic idiopathic pelvic pain. We
found that the pain scores were significantly reduced in both
groups. However, a more significant reduction of pain score
was achieved by inferior hypogastric plexus blockade than
acupuncture (p < 0.0001). The post‑intervention pain score
in the women who underwent inferior hypogastric plexus
blockade was 2.2 ± 0.88, as compared to 4.7 ± 0.11 found
among the women in the acupuncture group (p < 0.0001),demonstrating a 72.6% success rate in the inferior hypogastric
plexus blockade group (evident by the disappearance
of all symptoms) compared to 54.5% in the acupuncture
group (p = 0.3737). Moreover, 25.5% of the women in the
acupuncture group compared to 6.5% of the women in the
inferior hypogastric plexus blockade group (p = 0.0294)
reported that they did benefit from the treatment, indicating
that acupuncture when used for CPP was associated with a
high failure rate, although some studies demonstrated a high
success rate with acupuncture but not for CPP.
These results indicate that inferior hypogastric plexus
blockade was superior to acupuncture in producing fast pain
relief and significant reduction of pain intensity throughout
the study period, which reflect the patients’ satisfaction. The high failure rate in the acupuncture group after discontinuation
of treatment may be attributed to the fact that CPP is
primarily a reflexive pain of nociceptive origin. Therefore,
it may respond well to inferior hypogastric plexus blockade.
The inferior hypogastric plexus blockade technique
requires familiarity with the sacral anatomy and expertise
in fluoroscopy and refined needle technique. The procedure
was proved to effective and safe for diagnosis and treatment
of CPP.[10] By contrast, reports on the safety and efficacy
of acupuncture are diverse and inconclusive, and its use is
associated with some adverse reactions.
One series that used acupuncture for 1 year in 43 patients
with primary dysmenorrhea showed a 91% improvement
in symptoms and 41% decrease in analgesic use.[17]
Furthermore, a meta‑analysis performed to determine the
effectiveness and safety of acupuncture for pain in endometriosis
concluded that evidence to support the effectiveness
of acupuncture for pain in endometriosis is limited.[18]
This clinical improvement in pain with acupuncture can
be enhanced when infrared laser acupuncture is used.[19,20]
Compared with acupuncture, hypogastric plexus blockade
for pain relief in endometriosis was shown in one study to
significantly relieve pain immediately after establishing
the block, which is in good agreement with our findings.[21]
This high success rate obtained in acupuncture therapy for
dysmenorrhea might hold good for the treatment of pain due
to conditions other than CPP, as the nature of pain differs
according to etiology.
The success rate in our study is similar to that reported
by Schultz,[10] who introduced the transsacral approach to
blockade of the inferior hypogastric plexus. In his series,
which involved 11 patients who were treated with inferior
hypogastric plexus blockade for CPP, he reported a success
rate of 73%, with immediate satisfactory results and
no complications. In a case of CPP treated with inferior
hypogastric plexus blockade, clinical follow‑up showed
total pain reduction.[22]
Previous studies have shown that inferior hypogastric
plexus blockade plays a diagnostic role in the management
of chronic pelvic and perineal pains by providing information
that serves as guide for more specific global pain
management procedures, particularly when the pain is of
neoplastic origin.[23,24]
The minor differences in the success rate of this technique
between different studies may be due to technical
variation and operator experience, as the procedure requires
knowledge of the pelvic anatomy.
Transsacral approach has a similar success rate, with
no complications, as that of anterior superior hypogastric
plexus blockade, but the latter is associated with the risks
of injury to the overlying nerve, bowel, bladder, and common
iliac artery.[10] Thus, transsacral approach for inferior
hypogastric plexus blockade should be considered as an
alternative procedure for the management of CPP.
We conclude based on the findings of the study that
inferior hypogastric blockade had 72.6% success rate and
a significant effect on pain intensity reduction in a short period
in the management of CPP in women, when compared
with acupuncture. However, further study is warranted to
support this finding.