Fractional CO₂ Laser for Vulvar Tissue Rejuvenation: A Prospective Study

Abstract

Objective:

Aging and changes in hormone levels influence the appearance of the vulva, including the texture, pigmentation, and other manifestations, all of which may largely affect the physical and mental health of women. This study aimed to evaluate the efficacy and safety of fractional carbon dioxide (CO₂) laser treatment for vulvar rejuvenation in Chinese women.

Background:

The limited options currently available for vulvar rejuvenation raise concerns. There is insufficient evidence to determine whether the fractional CO₂ laser can safely and effectively rejuvenate the vulvar area for women of various ages and races.

Methods:

The study included 17 patients (mean age = 36.4 years) treated three times by continuous fractional CO₂ laser with an interval of 1 month between each session. The primary outcomes were changes in vulva texture and pigmentation. Treatment was evaluated using images of the patients. Baseline and posttreatment images were collected and evaluated using a scoring system from 0 to 3 to grade the vulvar texture and pigmentation changes. In addition, patients rated their degree of vaginal rejuvenation after the treatment using a scoring system from 0 to 3.

Results:

Fractional CO₂ laser treatment effectively and significantly increased vulvar texture and decreased vulvar pigmentation after three sessions (p < 0.05). Patients also self-reported noticeable improvement. There were no adverse reactions during the treatment and follow-up.

Conclusions:

Fractional CO₂ laser treatment is a safe and effective method for vulvar rejuvenation in women.

Introduction

The vulvar undergoes physiologic and age-related changes with loss of collagen and weakened vitality. Multiple factors contribute to such changes, including aging, hormone levels, friction, inflammation, drugs, and pregnancy.^1,2 Modifications of the female external genitalia affect the vulvar appearance, potentially changing the area's texture, smoothness, and overall appearance.³ Many women believe that genital appearance affects their sexual experience and satisfaction, which in turn can lead to a negative psychological impact.⁴

The options currently available for vulvar rejuvenation are limited. Surgical treatment such as labia majora augmentation may achieve tightening of the skin with little to no effect on surface changes such as texture and pigmentation.^5,6 Moreover, surgical intervention requires a lengthy recovery period and may not be a desirable option for women seeking fast recovery rejuvenation treatments. In this context, a safe, effective, and less-invasive medical treatment represents an important and attractive alternative for women undergoing vulvar rejuvenation. Energy-based devices, which act through collagen stimulation, provide a safe and viable option for vulvar rejuvenation treatment.⁷ Commonly used photoelectric treatments include radiofrequency technology,^8–10 erbium-doped yttrium aluminum garnet (Er:YAG) laser,¹¹ and fractional carbon dioxide (CO₂) laser.

The fractional CO₂ laser is an effective and commonly used treatment for skin rejuvenation.^12,13 Tissue microexfoliation can improve the texture and pigmentation of the skin. At the same time, the thermal effect can induce collagen contraction and proliferation, leading ultimately to tissue remodeling.¹⁴ Current evidence shows that tissue rejuvenation by fractional CO₂ laser can have long-lasting effects with studies showing effects to 12 months.¹⁵ The application of fractional CO₂ laser for female genital rejuvenation has been a relative recent intervention with promising outcomes. In a histological study by Samuels and Garcia increased staining of collagen and elastin, number of epithelial and cellular layers, and more mature tissue structure were found as postvaginal fractional CO₂ laser treatment.¹⁶ Despite the available studies on vulvar rejuvenation, strong evidence to support the rejuvenative effects on vulvar texture and pigmentation are lacking. This study aimed to examine the efficacy and safety of the fractional CO₂ laser in the treatment of vulvar rejuvenation in Chinese women.

Materials and Methods

This is a single-centre prospective study that evaluated the efficacy and safety of the fractional CO₂ laser to treat vulvar rejuvenation in Chinese women looking specifically at texture and pigment as outcomes. In the period between January 2018 and April 2019, a total of 17 women with a mean age of 36.4 years (30–53 years) were recruited. Sixteen of the 17 women had a history of at least one prior delivery. Table 1 shows the clinical and demographic characteristics of the patients. All patients included in the study provided written informed consent. Inclusion criteria were frequency of intercourse (greater than once a month), dissatisfaction by vulvar pigmentation and texture, and vulvar atrophy. Patients had no prior history of vulvar dermatoses, had not received any type of hormone replacement therapy, had not undergone any other locoregional treatments (chemical peels, hair removal procedure, etc.), and were not using any lightening or topical creams in the area.

Table 1.

Clinical and Demographic Characteristics of the Patients

	N	Mean ± SD or %
Age (years)	17	36 ± 7
Menopausal	4	24
No pregnancies	1	6
Caesarean section only	3	18
Vaginal delivery only	12	70
Caesarean and vaginal	1	6

SD, standard deviation.

The laser utilized in this study is the CO₂ RE Laser System (Candela Co. Ltd.), originating from the United States. The emission region of this laser falls within the Infrared spectrum, with a wavelength of 10,600 nm. A light mode, fractional coverage 40%, ring size 3, and energy fluence 6.5 J/cm² were selected considering the thinner skin of the vulvar compared to facial skin. The same equipment and energy parameters were used for all patients who were followed up for 1 month. The same parameters were used in all women to ensure consistency and reduce bias. The chosen parameters were light and superficial enough to be suitable for any skin type and thickness of skin in the treated area. Baseline and posttreatment two-dimensional (2D) images were taken using a digital camera (Nikon d90). Moreover, the photos were indeed taken in the same location under consistent lighting conditions. This ensured that the environmental factors remained constant and minimized potential variations that could affect the results. The study protocol was reviewed and approved by an ethics committee.

Preoperatively and intraoperatively

All participants received three laser treatments 4 weeks apart. The treated areas included the perineum, labia majora, mons veneris, clitoris, and vaginal orifice. The hair at the treated site was shaved before each treatment. Following disinfection, a topical anesthetic (5% lidocaine) was applied to the skin surface for 30 min. During the treatment, the equipment treatment hand was gently pressed on the skin surface, and the laser treatment was applied without overlap of any areas. Participants were required not to take tub baths within the first week posttreatment to reduce friction and irritation at the treatment site.

Outcome measures

Investigators assessed vulvar texture and pigmentation changes by comparing the baseline to the 1-month follow-up visit. Both aspects were evaluated using a 0–3 score system (0—no improvement; 1—mild improvement; 2—moderate improvement; 3—excellent improvement). The darkening and aging changes in the texture of the vulva were rated as mild, moderate, moderate-severe, or severe. These vulvar changes between images taken at baseline and 1 month after the final treatment were assessed using the following scale: score 0 = no significant change; score 1 = changes improved <1 grade; score 2 = 1 grade change; and score 3 = improvement >1 grade. According to their self-perception, patients completed questionnaires to determine the extent of improvement of vulvar rejuvenation 1 month after treatment. Treatment-induced discomfort/pain was measured using a visual analog scale, and any adverse event or side-effect was recorded. A pairwise t-test (R-3.6.0) was used to analyze statistical significance (p < 0.05).

Results

Evaluation of 2D digital images

We further investigated whether the fractional CO₂ laser improved vulvar rejuvenation by comparing images taken before and after three continuous treatments (Fig. 1). The comparison was made by the investigators using a 0–3 scoring system to represent the improvement. The digital images showed that all patients had at least mild improvement in the changes of vulvar pigmentation, including 4 with mild improvement, 10 with moderate improvement, and 3 with the excellent improvement. In terms of vulvar texture, 16 patients showed mild or above improvement, while 1 showed no changes before and after the treatment. Among those 16 patients, 9 had mild improvement, 5 had moderate improvement, and 2 had the greatest improvement. Postchanges in vulvar laxity and pigmentation indicate the efficiency of the fractional CO₂ laser in the treatment of vulvar rejuvenation. Samples of the images are available in Figs. 2–4. A p-value of <0.05 was found in all data indicating statistical significance.

FIG. 1.

Improvement in vulvar rejuvenation. Based on the evaluation of digital 2D images. Score: 0—no improvement; 1—mild improvement; 2—moderate improvement; 3—excellent improvement. 2D, two-dimensional.

FIG. 2.

Vulvar 2D image of Patient A. (A) Was taken at the baseline and (B) at the 1-month follow-up. The pigmentation and texture of the vulva showed an excellent improvement.

FIG. 3.

Vulvar 2D image of Patient I. (A) Was taken at baseline and (B) at 1-month follow-up. The pigmentation and texture of the vulva showed a moderate improvement.

FIG. 4.

Vulvar 2D image of Patient I. (A) Was taken at baseline and (B) at 1-month follow-up. The pigmentation and texture of the vulva showed a mild improvement.

Self-assessment results

We investigated the perceived efficiency of the fractional CO₂ laser for the treatment of vulvar rejuvenation by performing a self-assessment questionnaire to all 17 patients. Based on the patients' questionnaire responses, vulvar appearance showed significant improvement after three continuous treatments (p < 0.05). Among these participants, four had the greatest improvement, six had moderate improvement, and seven had mild improvement (Fig. 5). Four patients consciously experienced an increase in the sense of touch in their sexual life, thereby being easily aroused during their sexual life, which positively contributed to the experience of sexual intercourse.

FIG. 5.

Improvement in vulvar appearance. Based on patient's self-assessment questionnaire. Score: 0—no improvement; 1—mild improvement; 2—moderate improvement; 3—excellent improvement

Safety

The safety of the fractional CO₂ laser in the treatment of vulvar rejuvenation was evaluated using a pain assessment score (0–10) at the time of treatment, where 0 means no pain and 10 means the most severe pain. All participants showed no or tolerable mild pain.^17,18 Eleven patients scored 1, four patients scored 2, and two patients scored 0. Five participants self-reported mild itching at treatment site within 1 week with spontaneous resolution a week afterward. No other adverse event or side effect was observed during treatment and follow-up.

Discussion

The vulvar appearance changes with aging and decreasing hormone levels.³ Changes in collagen and elastic fibers lead to the appearance of textural changes accompanied by sagginess, loss of firmness, and loss of elasticity. These changes are often accompanied by increased pigmentation. Such changes can have a negative impact on the well-being and quality of life of the women. Genital rejuvenation treatments have increased in popularity over the last few years to address the abovementioned issues, in addition to improvement in vaginal health and urinary incontinence.¹⁹ The most popular studied vulvo-vaginal energy-based treatments include the Er:YAG, CO₂ laser, and radiofrequency.²⁰ When any organ is photostimulated, in addition to the organization and types of collagens, the extracellular matrix is also modified. The fractional CO₂ laser has been shown to induce collagen contraction by thermal effect, promotes new collagen synthesis, and decreases atrophy and laxity of the vulvar tissue.¹⁸ CO₂ laser can reach all the temperature thresholds necessary to effectively ablate and coagulate tissue. A vaporization procedure improves epidermal texture and pigmentation, and coagulation zones extend beyond ablation zones. Although there is currently no research comparing the therapeutic effects of different energy equipment on rejuvenation of female vulva, CO₂ laser seems to have the most significant impact based on current studies.²¹ The fractional CO₂ laser has been used to treat genitourinary syndrome of menopause and stress urinary incontinence in postmenopausal women.^22,23 However, there is currently a lack of evidence to prove that fractional CO₂ laser can safely and effectively rejuvenate the vulvar of women of different ages and races, and in particular with objectives such as “texture” and “pigmentation.” The current available evidence shows favorable results in the use of fractional CO₂ in female genital rejuvenation with the limitation being that the available data are mostly among postmenopausal women. Our study is the first to examine the vulvar changes in premenopausal women looking specifically at vulvar changes rather than the reported vaginal changes in most studies.²⁴

Many studies and clinical trials have proved the safety and effectiveness of fractional CO₂ laser treatment for facial rejuvenation.²⁵ Still, very few studies have researched the aspect of vulvar tissue rejuvenation. Common posttreatment side effects of CO₂ laser treatment in facial rejuvenation include pain, edema, infection, and postinflammatory hyperpigmentation.²⁶ The latter occurs more frequently in Fitzpartrick skin types III and IV.²⁷ Participants in our study experienced no discomfort or only minor adverse effects (tolerable pain, mild itching), which disappeared within a week. Based on the study results, the lower risk of adverse events may be associated with UV-unexposed and treatment parameters. This study used the same irradiation parameters in all patients, so the impact and safety of different parameters on treatment efficacy are unknown. Therefore, we recommend cautious parameter selection when attempting to use this method for treatment. There was robust patient compliance with treatments, possibly related to the low rate of adverse effects and high levels of self-perceived improvement by the patients. Our results suggest that fractional CO₂ laser can rejuvenate the vulva of women of different ages. Of the 17 patients in this study, 10 were 30–39 years old, and 7 were over 40 years old, including 4 menopausal patients. Although the varied age range may cause age-related bias, there were varying degrees of improvement in the vulvar appearance of all participants at different ages, with relatively high satisfaction. After three continuous fractional CO₂ laser treatments, the appearance of the genitals of all patients was improved to varying degrees. In addition, four patients reported increased vulvar sensation. The four participants who reported significant improvement in vulvar sensation consisted of one participant in the menopausal stage, one in the 40–50 age group, and two in the 30–40 age group. They were more sensitive to friction and touch, which improved the sexual experience. This may be related to the increased density of small and medium nerve fibers in the dermis and the increased nerve sensitivity due to laser heating,¹⁸ and Agostino et al.²⁸ stated that CO₂ laser stimulation on the human skin activate C-type receptors.

After three continuous fractional CO₂ laser treatments, the appearance of the genitals of all patients was improved to varying degrees. However, the number of patients was small, and the follow-up period was short. Further studies with large sample sizes and long-term follow-up are needed to determine the efficacy of maintenance. However, there are many factors that can affect the effectiveness of treatment. First, the treatment variability, the mild improvement in vulvar texture observed among the patients could be attributed to the natural variability in individual response to the treatment. Factors such as skin type, genetics, hormonal levels, and overall health might influence the extent of improvement. Second, patient demographics, including age and skin type, can play a significant role in the treatment outcomes. Younger patients might exhibit a more robust response due to increased collagen production and better tissue regeneration. Additionally, patients with certain skin types (e.g., lighter skin) might respond more positively to the treatment compared to those with darker skin, owing to differences in melanin content and skin structure. Factors such as diet, exercise, hormonal balance, and overall health can influence the body's ability to heal and regenerate tissue. These factors could be explored further to understand their impact on treatment efficacy. Genetic variations among individuals can impact their response to treatments. Patients with certain genetic predispositions might be more prone to experiencing mild improvements in vulvar texture. To gain a deeper understanding of these factors, future research could focus on conducting larger-scale studies with a diverse patient population. This would help identify trends and correlations between patient characteristics (age, skin type, genetics, etc.) and treatment outcomes. Additionally, exploring the molecular and cellular mechanisms underlying the observed improvements could shed light on the potential limitations and avenues for enhancing treatment effectiveness. Regarding the seven patients who considered their improvement to be mild, it is important to note that individual perceptions of improvement can be influenced by a variety of factors, including personal expectations, cultural norms, and psychological factors. While we did not conduct individual discussions with each patient to assess their perception of improvement, we acknowledge that such discussions could provide valuable qualitative insights. However, the primary aim of our study was to quantitatively assess patient's satisfaction using a standardized questionnaire, allowing for a consistent and objective measure across the participant cohort. The decision to utilize a satisfaction questionnaire on a scale of 0–3 was based on established research practices and the need for a concise and easily interpretable measure of patient's satisfaction. While more in-depth discussions could potentially yield richer qualitative data, the use of a standardized scale allows for efficient comparison and statistical analysis, aiding in the overall assessment of treatment outcomes. In future research, incorporating individual discussions alongside standardized questionnaires could offer a comprehensive understanding of patients' perceptions and expectations, providing a more holistic view of treatment outcomes. In conclusion, our study showed that after three treatment sessions, this study showed that fractional CO₂ laser treatment effectively decreased vulvar pigmentation and increased texture and is a safe option for women of different ages seeking vulvar rejuvenation. This is the first reported study to look at texture and pigmentation of the vulva as a result of fractional CO₂ laser with a high number of premenopausal patients.

Authors' Contributions

C.L. and W.Z. have made substantial contributions to the design of this study, and they both performed the statistical analysis and interpretation of data. C.L. participated in acquisition of date and analysis. X.Y. collected important background information and made valuable contribution to acquisition of date. All authors are involved in drafting the article, and approved the final article. All authors agreed to be accountable for all aspects of the work.

Ethical Approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was conducted under the oversight and approval of the Shanghai Dermatology Hospital Ethics Committee. The study was designed and carried out in accordance with the ethical guidelines and principles outlined by this committee. The approval number for this study is Protocol number: 2018-01, which was obtained before the commencement of the research.

Informed Consent

All patients included in this study signed their informed consent to participate.

Author Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.