Published research
In this section of the website we report on selected studies from published research on vulval pain and make our own comments on what is reported. For more information on the studies published see the PubMed database of studies at www.ncbi.nlm.nih.gov/pubmed. We felt that it would be important for women to learn about current research as a means of opening up treatment options. At the moment there is a big gap between research that is reported and options that filter down to the patient.
TREATMENT OF VULVODYNIA
I Studies examining the use of anticonvulsants, antidepressants or other drugs for vulvodynia
II Studies examining the use of physiotherapy for vestibulodynia
III Studies examining the use of psychosexual interventions for vulval pain
IV Studies examining the use of stress management and psychological therapies for vulval pain
I Studies examining the use of anticonvulsants, antidepressants or other drugs for vulvodynia
Self-management, amitriptyline, and amitriptyline plus triamcinolone in the management of vulvodynia.
J Womens Health (Larchmt). 2009 Feb;18(2):163-9.
Brown CS, Wan J, Bachmann G, Rosen R.
Departments of Pharmacy, Obstetrics and Gynecology, and Psychiatry, University of Tennessee Health Science Center, Memphis, Tennessee, USA. csbrown@utmem.edu
Summary
OBJECTIVE: To conduct a prospective study to determine the efficacy of self-management interventions, amitriptyline, and amitriptyline plus topical triamcinolone in reducing vulval pain in women with vulvodynia.
METHODS: This was a randomized, prospective study of 53 women between the ages of 18 and 72 with vulvodynia. Participants undertook one of three treatment interventions for a period of 12 weeks: self-management, oral amitriptyline (10-20 mg/day), or topical triamcinolone plus oral amitriptyline (10-20 mg/day). The McGill Pain questionnaire (MPQ) was used to measure changes in qualitative pain using the pain rating index (PRI) and in quantitative pain using the present pain intensity (PPI) scale.
RESULTS: Of the 53 randomized subjects, 43 completed the trial. There were no statistically significant differences in PRI or PPI scores among the three treatment groups. Significant within-group differences were observed in the self-management group on the PRI and in the amitriptyline group on the PPI.
CONCLUSIONS: This first randomized, prospective trial suggests that self-management has a modest effect and that low-dose amitriptyline (with and without topical triamcinolone) is not effective in reducing pain in women with vulvodynia.
VPS comments
Comments on study
This is the best type of research to be carried out in medicine – a randomised trial when a coin is tossed and the individual gets treatment A or B (or in this case A, B or C). It eliminates bias on the part of the doctor and the patient. This type of research is sadly lacking in vulval disease, although randomised trials can be difficult to set up e.g. researching the benefit of the low oxalate diet would be difficult because how can you control for a diet? The McGill pain questionnaire is a method of objectively assessing pain in patients and is useful to compare groups as it gives a score.
Outcome of study
This study suggests that there is no difference in outcome between self-management, amitriptyline tablets and amitryptyline and triamcinolnone (which is a steroid ointment applied to the vulva). Negative studies are worth reporting in the medical literature but are less frequently reported than positive studies, so it is interesting to note no difference with the treatments the authors have suggested. General clinical practice in the UK is to try a drug such as amitriptyline as an initial treatment in those women with unprovoked vulvodynia and there is much literature to suggest it does work. This study suggests that the benefits might not be as great as we can expect. For further information on the drug treatment of vulvodynia see our page Antidepressants and anticonvulsants. Topical steroids do not seem to benefit patients with unprovoked vulvodynia and in general these patients are not prescribed such drugs as the pain is neuropathic (from the nerve endings) and there is a risk of skin irritancy from the use of creams on the skin that can make symptoms worse.
Conclusions
For unprovoked vulvodynia self-management (i.e. education, good skin care, and painkillers) is recommended. Drugs such as the tricyclic antidepressants e.g. amitriptyline or nortriptyline (the latter has fewer side-effects) can be discussed with your doctor; however, we feel that the best way to tackle the chronic pain is to combine all the treatments and remain holistic!
Topical gabapentin in the treatment of localized and generalized vulvodynia.
Obstet Gynecol. 2008 Sep;112(3):579-85.
Boardman LA, Cooper AS, Blais LR, Raker CA.
Department of Obstetrics and Gynecology, Women and Infants’ Hospital of Rhode Island, Providence, Rhode Island, USA. lboardman@ihti.org
OBJECTIVE: To evaluate the clinical efficacy and tolerability of topical gabapentin in the treatment of women with vulvodynia.
METHODS: A retrospective study was designed to ascertain clinical responses to topical gabapentin. Patient demographic and medical characteristics, including present and prior treatment for vulvodynia, were routinely collected. The final outcome was defined by a comparison between pretreatment and posttreatment mean pain scores based on a discrete visual analog scale of 0 to 10. Categorical data were compared by Fisher exact test, continuous variables between groups by the Wilcoxon rank sum test, and mean change in pain score between pretreatment and posttreatment by paired Student t test.
RESULTS: Between January 2001 and December 2006, 51 women with vulvodynia (19 or 37% with generalized vulvodynia, 32 or 63% with localized) were treated with 2% to 6% gabapentin. After a minimum of 8 weeks of therapy, the mean pain score among the 35 evaluable women was significantly reduced from 7.26 to 2.49 (mean change -4.77, 95% confidence interval -5.47 to -4.07). Overall, 28 of 35 (80%) demonstrated at least a 50% improvement in pain scores. Among patients with localized vulvodynia, sexual function improved in 17 of 20 with evaluable results (6 of 9 reinstituted vaginal intercourse, whereas all 11 patients experiencing decreased frequency of intercourse reported increased frequency after treatment). Discontinuations occurred in 7 of 50 (14%) treated.
CONCLUSION: Topical gabapentin seems to be well-tolerated and associated with significant pain relief in women with vulvodynia.
LEVEL OF EVIDENCE: III.
VPS comments
Comments on study
This study was retrospective, i.e. the data was collected some time after the treatment had finished. This does make the data slightly weaker than if the data was collected prospectively (the recall of the pros and cons of treatment is better this way). The benefits of treatment were measured using a visual analogue score which is a well-tested method of assessing pain objectively (0/10 is no pain and 10/10 is the worse pain ever). Many pain clinics use this technique to objectively assess pain levels as well as asking the patient ‘how much pain do you have?’ which is more subjective. The treatment is novel. Gabapentin is a second line drug treatment for chronic unprovoked pain (not just vulval pain). Is it usually tried when patients do not respond to drugs such as the tricyclic antidepressants. It is usually given in tablet form and this study is a first as it is used as a cream which might potentially avoid the side-effects of a tablet preparation.
Outcome of study
80% of the women at follow-up had reported an improvement of greater than 50% which is very encouraging. Many women also resumed sexual intercourse. It is not clear what the side-effects of treatment were, however, as cream can irritate vulval skin and 14% of patients discontinued treatment.
Conclusions
This was an American study and it is worthy of a similar trial in the UK to see if such good results can be reproduced. Gabapentin cream is not routinely available in the UK and it is not clear to us at the VPS if the drug can be made up. It is also not clear also whether it is worth trying if you have failed on the tablet form of gabapentin. You might need to discuss this with your doctor (who will then need to discuss it with a pharmacist).
II Studies examining the use of physiotherapy for vestibulodynia
The use of Amielle vaginal trainers as adjuvant in the treatment of vestibulodynia: an observational multicentre study.
Medscape J Med. 2008 Jan 30;10(1):23.
Murina F, Bernorio R, Palmiotto R.
V. Buzzi Hospital, Milan, Italy. filippomurina@tin.it
OBJECTIVE: To assess the effectiveness of a specific set of vaginal dilators (Amielle Comfort) as a part of vestibulodynia therapy.
STUDY DESIGN: Fifteen women referred for vestibulodynia, localized vulvodynia, were advised to use vaginal dilators (Amielle Comfort) accompanied by standardized instructions, after previously receiving 1 or more therapies for the vestibulodynia.
RESULTS: The post-treatment Marinoff scale for dyspareunia significantly improved in patients after vaginal dilator treatment compared with baseline values (2.2 +/- 0.4 vs 1.1 +/- 0.9; P < .01), and the Female Sexual Function Index scores were significantly improved compared with the prestudy values (16.3 +/- 5.5 vs 25.3 +/- 7.5; P < .01).
CONCLUSION: Among women with previous therapy for vestibulodynia, vaginal dilator use was associated with improvement in symptoms. Vaginal dilators can play an important role in overcoming pelvic floor muscular responses that remain and sometimes increase after pain perception has decreased.
VPS comments
Comments on study
Women with vestibulodynia have touch-sensitive areas on the vulva (see our page Vestibulodynia). This phenomenon is called allodynia when the sensation of touch/pressure is felt as pain. We are not quite sure why this happens, but it can produce sexual pain and pain with the use of tampons. For some women understandably, there is a fear of touching the vulval area – a phobia, which can lead to sexual avoidance, so when sex is finally attempted there can be vaginismus (or involuntary contraction of the vaginal muscles) which leads to more pain. There has been a change in focus on vestibulodynia treatment to encourage women to touch and massage the vulval area. This is called desensitisation and it can help reduce the allodynia problem and increase confidence in having penetrative sex. The use of the vaginal trainers, or dilators (of which Amielle is one make) can also help (see the paragraph on dilators on our Physiotherapy page for more info on vaginal trainers). These pieces of plastic can be introduced into the vagina to help relax the pelvic floor muscles and allow the woman to feel more comfortable with an object in the vagina other than a penis. Relaxation is the key!
Outcome of study
The trial simply uses these trainers and assesses their benefit with standardised questionnaires before and after treatment. They do seem to help some of the women.
Conclusions
This is a simple trial and something that women with vestibulodynia can try themselves as the trainers can be bought over the counter (a simple vibrator might be tried in its place). See our page Physiotherapy, which gives information on densitisation and also includes instructions on pelvic floor exercises which can help. It is worth noting that this treatment can take time to work and needs investment and perseverance – it may take several months for the benefit to become apparent.
III Studies examining the use of psychosexual interventions for vulval pain
For discussion of several studies relating to sexual therapy, including psychosexual therapy, please see Gundi Kiemle’s article ‘Psychosexual therapy’.
IV Studies examining the use of stress management and psychological therapies for vulval pain
This section is currently under construction – watch this space for updates!
V Studies examining the use of holistic treatments such as acupuncture, diet and exercise for vulvodynia
Influence of dietary oxalates on the risk of adult-onset vulvodynia.
J Reprod Med. 2008 Mar;53(3):171-8.
Harlow BL, Abenhaim HA, Vitonis AF, Harnack L.
Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis 55454, USA. harlow@epi.umn.edu
OBJECTIVE: To examine the relationship between dietary oxalates and the development of vulvodynia.
STUDY DESIGN: We conducted a population-based, case-control study of women with and without vulvodynia from nine ethnically diverse Boston-area communities. Conditional logistic regression analyses were used to estimate the odds of developing vulvodynia as a consequence of self-reported consumption patterns of high-oxalate foods and total weekly dietary oxalate. Oxalate consumption was referenced prior to the onset of symptoms in cases and to a matched reference date among controls.
RESULTS: Baseline clinical characteristics were similar among the 242 cases and 242 controls except for a higher reported incidence of pain/difficulty with first tampon insertion among cases (46.3% vs. 32.2%, p < 0.01). After adjusting for potential confounders, no differences were observed in consumption patterns of different high-oxalate foods between cases and controls, and there was no increase in risk of developing vulvodynia with increasing tertiles of estimated oxalate intake. In addition, we saw no association between increasing consumption of various food items high in oxalate content and the risk of vulvodynia.
CONCLUSION: Dietary oxalate consumption does not appear to be associated with an elevated risk of vulvodynia.
VPS comments
Comments on study
Can dietary factors influence vulval pain levels? Possibly. Our own survey of women with vulval pain from 1998 suggested that in around one third of women with vulval pain, the pain can be aggravated by certain foods (commonly yeast products, sugary products and alcohol); however, this was a questionnaire survey and was limited in its conclusions. It is not clear what in the diet can cause or aggravate vulval pain but there is certainly a link. The oxalate theory for pain is covered in The low-oxalate diet. Initial medical reports were very promising with some women reporting relief of symptoms with a low-oxalate diet and calcium citrate supplements (the latter to help clear the oxalates from the body); however, subsequent studies (including this one) fail to make the link.
Outcome of study
This study reports no difference between the dietary habits of women with vulvodynia and those of controls, suggesting that oxalates might not be responsible for the development of symptoms. This was a population-based study, however, and it does not take into account the benefits to the individual women.
Conclusions
More research is needed in this area. Dietary factors might not be responsible for the development of symptoms, but we can draw no conclusions from this study for women with vulvodynia on how diet can influence the level of day-to-day pain. We would not discount the diet – vulvodynia connection, but would encourage you to explore this area for yourself.
Is modified vestibulectomy for localized provoked vulvodynia an effective long-term treatment? A follow-up study.
J Reprod Med. 2008 Jun;53(6):435-40.
Eva LJ, Narain S, Orakwue CO, Luesley DM.
Department of Gynaecological Oncology, Pan Birmingham Cancer Centre, Birmingham, England. loiseva@supanet.com
OBJECTIVE: To determine whether vestibulectomy is an effective long-term treatment and investigate the levels of patient satisfaction in women with localized provoked vulvodynia, and to provide long-term follow-up data from a cohort of women whose short-term success rates have been published previously.
STUDY DESIGN: A retrospective case note review of 110 women with localized provoked vulvodynia and follow-up patient questionnaire. Patients were asked to quantify their pain scores before surgery, at 2 months after surgery and 1 year after surgery and score their satisfaction levels.
RESULTS: Mean pain scores continued to improve throughout the first postoperative year. The mean score was 9.17 preoperatively, 5.24 at 2 months after surgery and 2.48 at 1 year after surgery. Eighty-three per cent of patients would recommend the procedure as effective treatment of localized provoked vulvodynia. The overall mean satisfaction score was 7.96, and long-term success appears to be reflected by short-term results.
CONCLUSION: Vestibulectomy is an effective long-term treatment for women with provoked localised vulvodynia; the procedure is associated with high levels of patient satisfaction and low complication rates. Short-term success appears to be a good indicator of long-term improvement, and improvement continues throughout the first postoperative year.
VPS comments
Comments on study
Vestibulectomy is the surgical removal of skin from the vestibule (inner labia) for women with sexual pain (vestibulodynia). We have covered the procedure in more detail on our page Surgery for vulval pain. It has always been a controversial treatment as to many doctors and patients it seems a drastic step. Anecdotally there were concerns over the long-term benefits of the procedure and whether the procedure made patients worse. This study aims to address the benefit to patients up to one year after the procedure which is a good length of time to assess success of treatment. It is not a prospective study in that it is depending on patients’ recall of their symptoms.
Outcome of study
The results are encouraging with many women satisfied up to one year post surgery.
Conclusions
It is difficult to suggest that surgery is of benefit to all women with vestibulodynia as this was a well-selected group of women with vulval pain. Some women might have refused surgery and we have no comment on those women. Did they get better with physical treatment e.g. massage and trainers? If surgery has been offered to you by your doctors then the paper does suggest that it has some long-term benefits. Surgery should not be offered to women with unprovoked pain as this is unlikely to benefit. Can a vaginal TENS machine (transcutaneous nerve stimulator) help for women with vestibulodynia (sex related pain)?
Transcutaneous electrical nerve stimulation to treat vestibulodynia: a randomised controlled trial.
Brit J Obstet Gynaecol. 2008 Aug;115(9):1165-70.
Murina F, Bianco V, Radici G, Felice R, Di Martino M, Nicolini U.
Outpatient Department of Vulvar Disease, V. Buzzi Hospital, Milan, Italy. filippomurina@tin.it
OBJECTIVE: To assess the benefits of transcutaneous electrical nerve stimulation (TENS) in the treatment of vestibulodynia.
DESIGN: Double-arm randomised placebo-controlled trial.
SETTING: An outpatient department for vulval disease.
POPULATION: Forty women with vestibulodynia, a vestibular discomfort mostly reported as a burning pain, occurring in the absence of relevant visible findings or a specific, clinically identifiable, neurological disorder.
METHODS: Twice a week active TENS or sham treatment were delivered through a vaginal probe via a calibrated dual channel YSY-EST device. Women of both groups underwent 20 treatment sessions.
MAIN OUTCOME MEASURES: Visual analogue scale (VAS), the short form of the McGill-Melzack Pain Questionnaire (SF-MPQ), the Marinoff Scale for dyspareunia and the Female Sexual Function Index questionnaire (FSFI) were assessed at baseline, at the end of treatment and at follow up 3 months after the end of treatment.
RESULTS: The VAS and SF-MPQ scores (6.2 +/- 1.9 and 19.5 +/- 11.9 before treatment, respectively) improved significantly in the active TENS group (2.1 +/- 2.7, P= 0.004 and 8.5 +/- 10.7, P= 0.001, respectively), but not in the placebo group. The Marinoff dyspareunia scale and the FSFI also showed a significant improvement.
CONCLUSIONS: TENS is a simple, effective and safe short-term (3 months) treatment for the management of vestibulodynia.
VPS comments
Comments on study
A TENS machine is a well established, safe means of alleviating chronic pain. Many systems are available to buy over the counter and are they are commonly used for back pain. The system usually involves a series of pads that are attached by wires to a machine which provides a source of electrical stimulation. The exact mechanism of how the TENS machine works is not known. In the skin there are many different types of nerve fibres which are used for specific functions. Motor nerves come from the central nervous system (brain and spinal cord) and have an action to perform, e.g. contracting muscles, whereas sensory nerves report information to the brain such as sensations, sight, smell etc. In the skin there are several different types of nerves – C fibre activation sends the sensation of pain to the brain whereas A fibre activation sends the sensation of touch, pressure, our temperature etc. Electrical stimulation from a TENS machine at a certain setting would activate the A fibres and for reasons not clear would inactivate the C fibres giving pain relief. This electrical stimulation might simply ‘switch off’ the nerve fibres. (See below for the details of the machine.)
Outcome of study
The researchers measured the outcomes of their study using patient filled questionnaires. These give a scoring system to compare before and after. There was a significant benefit from the treatment compared to the placebo arm. Patients who had the treatment noticed better sexual functioning and reduced pain levels. One limitation of the study was that patients were only followed up for 3 months.
Conclusions
Women with sexually-related pain from vestibulodynia may benefit from treatment from TENS using a vaginal probe. The authors conclude that the system can be used at home after a period of supervision rather than in the clinic. It is worth exploring as a treatment. Its value in women with unprovoked pain remained unclear – some women with unprovoked vulvodynia might experience an increase in pain but further research is needed.
The TENS group of patients received an electrical stimulation through a calibrated dual-channel TENS unit called a YSY-EST device delivered through a plastic vaginal probe containing sensors. This probe (PERIPROBE or VAG2ST) is 20mm in diameter and 110mm in length and held in the vagina for 15 minutes of 10Hz frequency and pulse duration of 50 microseconds followed by 15 minutes of 50Hz frequency and pulse duration of 100 microseconds (i.e. each session was 30 minutes in total). 20 sessions were given twice a week. Most TENS machines allow the user to choose between continuous, burst and modulated outputs. A modulated output is better to the patient in terms of comfort as it fluctuates from a pre-set limit to zero and back again. We are currently looking into where this system can be purchased in the UK. If you are interested please email us at info@vulvalpainsociety.org.