The Effect of Vielle on Sexual Response Induced by Masturbation in Female Volunteers

Alan Riley,
M.Sc, MB, BS, MRCS, FFPM Professor of Sexual Medicine Lancashire Postgraduate School of Medicine and Health University of Central Lancashire Preston PR1 2HE.

Elizabeth Riley
B.Sc (Hons)Research Sex Therapist & Director, Sagacity Associates Ltd. Kings Park, Cwmann, Carmarthenshire, SA48 8HQ

Abstract
Vielle is a finger-cot shaped device that has been designed to increase digital clitoral stimulation when worn on a finger. Effects on the sexual response of 16 female volunteers of Vielle-use and non-use (control) were compared in a randomised within subject study in which each subject reported on 4 episodes of Vielle-use and 4 control episodes of masturbation. Orgasm latency was timed using a stop clock.

Vielle-use, compared to non-use, was associated with a shorter orgasm latency (5.57 vs 13.05 minutes, p = 0.005), an increased orgasm attainment rate (95.3% vs 82.8%, p = 0.044) and enhanced ease of attaining orgasm (4.25 va 3.0, p = 0.005). Vielle-use was also associated with increased orgasmic satisfaction (4.0 vs 3.0, p = 0.001).

On the basis of these results, Vielle may be helpful in the treatment of women who experience difficulty or delay in attaining orgasm. The improvement in orgasm consistency with Vielle-use may be useful in the management of other forms of female sexual dysfunction.

Introduction
A large general practice-based population, anonymous questionnaire study conducted in England revealed 41% of the female respondents reported having an ongoing sexual problem, and 68% of women reported having a sexual problem at sometime in their lives (Dunn, Croft & Hackett, 1998).

The most frequent ongoing complaint was vaginal dryness reported by 28% of the respondents. Orgasmic dysfunction (climax never or rarely experienced) was the second most frequent symptom reported by 27% of the female study subjects. The results from this study are comparable to those from other studies.

For example, an epidemiological study undertaken in America revealed that 43% of female participants aged 18 to 59 years experienced sexual dysfunction during the past year (Laumann, Paik & Rosen, 1999). Inability to achieve orgasm was reported by 24.1% of the women in this study.

Similarly, in a representative sample of Swedish women, aged 18 to 74 years, 48% had a sexual dysfunction (Fugle-Meyer, 2001). The most common symptom was hypoactive sexual desire followed by orgasmic and arousal disorders.

Although some women present for treatment with a single sexual dysfunction, the majority (70%) have a combination of impairment of sexual desire, arousal and orgasm (Talakoub, Munarriz, Hoag, et al, 2002).

Whilst there is increasing interest in looking for organic aetiologies for such sexual symptoms (Talakoub, Munarriz, Hoag, et al, 2002) and pharmacological approaches to their alleviation, the mainstay of management of female sexual dysfunction continues to be sex therapy.

Directed masturbation is a component of most sex therapy programmes for women. This has been shown to be effective in overcoming anorgasmia (Lobitz & LoPiccolo, 1972; LoPiccollo & Lobitz, 1972; Riley & Riley 1978; ) and is claimed to be useful in the management of hypoactive sexual desire (Hurlbert, 1993; Hurlbert, White & Powell, 1993).

This is probably because sexual activity that results in orgasm has a higher re-inforcement effect, leading the woman to engage in more sexual activity (Arafat & Cotton, 1974).

The use of vibrators is often advocated in directed masturbation programmes for women (Riley & Riley, 1978). Although modern vibrators are less noisy and obtrusive than earlier versions, their acceptance is not universal, especially in women seeking help for sexual difficulties. With this in mind, Vielle (Vielle TM CST Medical Ltd), was designed as a means to enhance clitoral stimulation.

It resembles a finger cot with specially positioned nodules on the palmar aspect. It is made from PVC and is worn on a finger during digital stimulation of the clitoris or other genital structures. This study was undertaken to investigate Vielle-use on the sexual response of female volunteers.

Method
Potential subjects were recruited from the investigator’s volunteer panel. The nature of the study was explained and they took away a Subject Information Sheet to read at home and, where appropriate, discuss it with their sexual partner.

They returned to the research clinic where any questions they had about the study were answered. Subjects who were willing to take part in the study, then provided written informed consent.

Each subject was given 4 Vielle devices, a tube of lubricant (Clinijel ®) and a pack of Event Record Forms (ERFs) to complete after each study session. The subject was also given an electronic stop clock (MG07H, Maplin) and a randomisation schedule.

Each subject reported on 8 episodes of self-masturbation comprising 4 using Vielle and 4 without using Vielle or any other device. The order of Vielle-use/non-use was determined from the randomisation schedule. The subject was asked to start the stop clock when she started to masturbate and to stop it at the onset of orgasm. She recorded the time taken to attain orgasm in the ERF.

After each experimental session, the subject completed an ERF, Subjects were asked to undertake the experimental sessions within the time frame 12 to 24 hours after a previous sexual experience (experimental or otherwise) and to keep each session as similar as possible.

Throughout the study, subjects recorded any adverse effects they experienced during the study sessions. At the end of the study, each subject completed a global outcome questionnaire comprising two questions.

Subjects:
Sixteen healthy female subjects, aged 18 to 58 (mean 36.6) years were studied. The subjects were known, from self-reporting, to be orgasmic in response to masturbation. Subjects were excluded from the study if they had known allergy to PVC or lubricant (Clinijel®), if they were pregnant, three months or less post partum or reported an ongoing painful condition of the genitalia.

Women taking medication likely to impair sexual arousal and/or orgasm attainment and women who had started or changed hormonal treatment (eg HRT or oral contraception) within the past 3 months were also excluded.

Ethical approval
The study was approved by the Psychology Department Research Ethics Committee of the University of Central Lancashire, Preston.

Data, collection, management and analyses
All study data were collected on the study report forms and questionnaires. Subjects were identified on all study-related documentation only by a study number. The ERF comprised ten items. The items directly relating to the subjective elements of the sexual response were derived from the Arizona Sexual Experiences Scale (McGahuey, Gelenberg, Laukes et al, 2000).

The ten items on the ERF were:

1.Did you experience orgasm?
(Response: Yes / No)

2.How long did it take you to reach orgasm or if you did not have an orgasm, how long did stimulation last?

(Response: time in minutes and seconds)

3.Was Vielle used in this event?
(Response:Yes / No)

4.How strong was your sex drive today?
(Response: 6 point scale ranging from No sex drive (0) to Extremely strong (5))

5.How easily were you sexually aroused (turned on) during this event?
(Response: 6 point scale ranging from Unable to get aroused (0) to Extremely easily (5))

6.How easily did your vagina become moist or wet during this event?
(Response: 6 point scale, ranging from Did not get moist or wet (0) to Extremely easily (5))

7.How much excitement did you experience from stimulation of your genitals?
(Response: 6 point scale, ranging from No excitement at all (0) to Extremely strong excitement (5))

8.How easily did you reach orgasm during this event?
(Response: 6 point scale, ranging from Did not reach orgasm (0) to Extremely easily (5))

9.If you experienced an orgasm during this event, how satisfying was it?
(Response: 6 point scale, ranging from Extremely unsatisfying (0) to Extremely satisfying (5))

10.Did you experience any untoward events or effects during this event?
(Response: Yes / No, if yes, please describe as fully as you can)

The two global questions asked at the end of the study were:

1.What effect do you think Vielle had on how easily you reached orgasm?
(Response, Made it more easy, Had no effect, Made it more difficult)

2.What effect do you think Vielle had on your enjoyment of the sexual experience?
(Response: Made it more enjoyable, Had no effect, Made it less enjoyable)

Median scores for the responses for each item on the ERF for each subject, under each of the two experimental conditions, were calculated and used in statistical analyses. Wilcoxon signed rank test was used to compare orgasm latency and the ERF item responses between Vielle-use and non-use. Attainment rates for orgasm were compared by the Fishers Exact test. Responses to the two global outcome questions were tabulated.

Results
All subjects completed eight experimental sessions. Not all subjects attained orgasm during all of the eight study sessions. Among all subjects, the orgasm attainment rate when Vielle was used was 61/64 (95.3%) compared to 53/64 (82.8%) attained orgasm during the 64 sessions when Vielle was not used. The difference in orgasm attainment between Vielle -use and non-use reached statistical significance (p =0.044).

The median and range orgasmic latency for each subject are tabulated in Table 1, which also shows the number of occasions in each treatment condition when orgasm was attained. Duration of stimulation for the events when orgasm was not attained is given in Table 2. Results from the ERF (except orgasm attainment) are summarised in Table 3.

Orgasm latency was significantly (p = 0.001) less when Vielle was used (5.57 minutes) than when it was not used (13.05 minutes). This is reflected in the responses to the question “How easily did you reach orgasm during this event?”; the score being significantly higher for Vielle-use than Vielle non-use (4.25 vs 3.0; p = 0.005). In response to the first global question, 11 (68.75%) of subjects considered Vielle made attainment of orgasm more easy and 5 (31.25%) reported it having no effect. No subject reported that Vielle made orgasm attainment more difficult.

Vielle-use is associated with a higher response score to “How satisfying was orgasm during this event?” than Vielle non-use (4.0 vs 3.0; p = 0.001). In response to the second global question, 11 (68.75%) subjects reported that Vielle-use made the sexual experience more enjoyable and 5 (31.25%) thought it had no effect. No subject reported Vielle made the sexual experience less enjoyable.

There are no statistically significant differences between Vielle -use and non-use for ease of arousal, vaginal wetness and excitement. There was also no difference in “strength of sexual drive” between the two treatment conditions.

Discussion
The sexual response is triggered by and progresses by effective sexual stimulation. This has been defined as the algebraic sum of positive (sexually stimulating) stimuli and negative (sexually inhibiting) stimuli (Riley 1997). Negative stimuli may be internal (eg performance anxiety, guilt) or external (eg distraction) and are usefully classified as arising directly or indirectly from predisposing, precipitating or maintaining factors (Hawton, 1985), Positive stimuli are generated centrally and peripherally. Centrally-generated positive stimuli are usually triggered by erotic input from the special senses whilst peripheral positive stimuli arise from mechanical stimulation of the genitalia or other erogenous zones.

The clitoris plays a pivotal role in the generation of peripheral sexual stimulation in the majority of women. The clitoris, prepuce and labia minora are richly supplied with a variety of types of specialised nerve receptors, each type responding to a different modality of stimulus (Krantz, 1978). For example, Meissnerís corpuscles and Merkel tactile discs respond to touch and are important for tactile discrimination, Pacinian corpuscles are triggered by deep pressure while Dogiel-Krause bulbs and Raffini corpuscles may be involved in the perception of warmth and sexual stimulation. They are generally present in large numbers in the prepuce of labia minora. The largest concentration of Pacinian corpuscles is in the corpus cavernosum of the clitoris and they are, therefore, exposed to pressure when the clitoris undergoes tumescence during sexual arousal. The nodules on Vielle were designed to enhance pressure applied to the clitoris and prepuce during external masturbation.

There are differences among women in the distribution of the various nerve endings (Krantz, 1958), which may account for interpersonal differences in genital sensitivity (Kaplan, 1974). This, in turn, may be one of the factors that account for the variation in duration and type of stimulation women require for their attainment of orgasm. Other factors that influence the amount of stimulation a woman requires to trigger orgasm include central modulation of the afferent signal arising from genital stimulation by sexually inhibiting signals alluded to above. This study has shown how marked are the interpersonal and intrapersonal differences in orgasm latency, under similar experimental conditions. Levin and Wagner (1985) determined orgasm latency from vaginal blood flow studies in 28 volunteers, who masturbated in the laboratory using their preferred method, including in two subjects a battery powered vibrator. Orgasm latency ranged from 0.75 to 25 (mean 7.8) minutes. Riley and Riley (1983; 1986) in their clinical pharmacology studies measured orgasm latency by means of a blinded stop clock. After placebo medication and with stimulation applied by means of a vibrator, orgasm latency ranged from 3.8 to 10.3 minutes. It is obviously not possible to compare orgasm latency across different studies as it is influenced by experimental conditions. In the present study, experimental conditions were standardised, as well as can be, across the eight study sessions making it possible to compare Vielle-use and non-use. It is obviously not possible to control subjects’ fantasy activity across sessions.

Although it was an inclusion criterion for this study that subjects were orgasmic in response to masturbation, not all subjects attained orgasm on all study sessions, even when stimulation was generally prolonged. One subject, on one occasion, stopped stimulation after only 7.23 minutes because of soreness (she has vulval lichen planus) all the other subjects ceased stimulation because they felt that orgasm would not be attained if they continued. Women in general are orgasmic only 40 to 80% of the time, regardless of the method of stimulation (Anderson Darling, Davidson & Cox, 1991). Hence factors other than nature and duration of genital stimulation influence orgasm attainment, even in sexually well-adjusted women.

Vielle-use was associated with higher orgasm attainment rate than when it was not used. Vielle-use also significantly reduced orgasm latency and enhanced satisfaction from orgasm. The large majority of women reported that Vielle made orgasm attainment more easy and enhanced their enjoyment of the sexual experience. Apart from vulval soreness in a subject who has lichen planus there were no reported adverse effects attributable to Vielle. Vielle may therefore be helpful in the management of women who experience orgasmic dysfunction which continues to be a frequent problem among women attending clinics. For example, Crowley (1998) reported that 15.2% of women attending her specialist psychosexual clinic in Bristol presented with orgasm problems and 26% of Muslim women seeking services at Family Planning Centres in Tehran had inhibited orgasm (Shokrollahi, Mirmohamadi, Mehrabi & Babaei, 1999).

Although in this study women themselves used Vielle during masturbation, it can also be worn by the woman’s partner to provide enhanced clitoral stimulation during foreplay. An observational study of Vielle-use is required to ascertain the role of the device in the management of orgasmic dysfunction and how amelioration of orgasmic dysfunction improves concomitant other forms of sexual dysfunction.

Conflict of interest
The study was funded by CST Medical Limited.