Vagina

Vagina

Overview and Definition

The vagina is a female reproductive organ that changes over the lifespan of a woman. It serves a multitude of functions in response to hormonal changes as appreciated during puberty, menstruation, pregnancy, and menopause, and plays a vital role in the female reproductive system and female sexual pleasure. As one of the primary organs of the internal female genital tract, the vagina is part of the internal genitalia of the female reproductive system, and the internal female sex organs form a pathway — the internal female genital tract — composed of the vagina, uterus, the paired uterine tubes, and ovaries.

Anatomy and Structure

Gross Anatomy and Dimensions

The vagina is an elastic muscular tube of 7 to 10 cm in length that extends from the vulva (female external genitalia) to the cervix of the uterus, where it ends in an anterior and posterior fornix. The vaginal canal is positioned between the urethra and bladder anteriorly, and the rectum posteriorly. The vaginal opening is in the posterior portion of the vulvar vestibule, behind the urethral opening. It is surrounded on either side by the labia minora medially and labia majora laterally. A thin perforated layer of hymen partially forms the entrance of the vaginal opening.

The vagina tilts posteriorly between the urethra and rectum, with the urethra bound to its anterior wall. If standing, the vaginal tube will point in a superoposterior direction to form a 45-degree angle with the uterus and approximately a 60-degree angle to the horizontal. The exact angle is variable depending on individual anatomy and with contents of the bladder and colon. Due to this tilting, the posterior wall of the vagina (8 to 10 centimeters) is longer than its anterior wall (7.5 centimeters).

During sexual arousal the vagina expands in both length and width. A series of ridges produced by the folding of the wall of the outer third of the vagina is called the vaginal rugae.

The vaginal fornix is a recess around the cervix and has anterior, posterior, and lateral parts. The posterior vaginal fornix is associated with the rectouterine pouch (of Douglas). The pubovaginalis, external urethral sphincter, urethrovaginal sphincter, and bulbospongiosus are the four muscles that compress the vagina and act as sphincters.

External Structures (Vulva)

When observed externally, the vulva appears covered or wrapped by folds of skin called the labia majora and labia minora, both of which are integral components of the vulva. The components of the vulva are the mons pubis, labia majora, labia minora, clitoris, urethra, vulvar vestibule, vestibular bulbs, Bartholin glands, Skene glands, and vaginal opening.

The primary function of the Bartholin glands is the production of a mucoid secretion that lubricates the distal vagina during intercourse. The glands become active after menarche and are normally impalpable. The pudendal nerve innervates the Bartholin glands, providing sensory and autonomic (parasympathetic) stimulation. Sensory innervation enables the perception of pain or discomfort, while autonomic stimulation supports the secretion of mucus for lubrication.

Histology and Wall Layers

The vagina is composed of four layers: (1) an inner layer of non-keratinized squamous epithelium containing no glands; (2) the lamina propria, rich in elastic fibers; (3) the muscularis layer of smooth muscle with inner circular surrounded by outer longitudinal layers; and (4) the adventitial layer, which merges with the adventitial layers of the bladder and the rectum. The entire vaginal wall thickness measures 2–3 mm in a reproductive-age woman but is usually thinner when estrogen levels are lower.

The epithelial layer is composed of a lower basal layer, several layers of parabasal cells, and multiple layers of intermediate and superficial squamous cells that progressively accumulate glycogen. Transverse epithelial folds dip into the third layer of muscularis and contribute to the elasticity of the vaginal walls, allowing intercourse and childbirth.

The vagina is lined with stratified squamous moist epithelium to protect the organ during intercourse and parturition. This epithelium responds to high estrogen at the time of ovulation by increasing the number of cell layers and by accumulating abundant glycogen. As epithelial cells are exfoliated, glycogen is released and metabolized by bacteria producing lactic acid. This lowers the pH in the lumen and inhibits the growth of pathogens.

The adventitia also contains a large amount of elastic fibers, which allow the vaginal wall to be both strong and flexible, which is particularly beneficial during childbirth.

Estrogen Sensitivity

The vagina, like the uterus and the bladder, is estrogen sensitive. Estrogen acts on receptors in the vagina to maintain the collagen content of the epithelium. Estradiol maintains acid mucopolysaccharides and hyaluronic acid, keeping the epithelial surfaces moist and well glycogenated and optimizing genital blood flow. The surface cells of the vaginal epithelium are cast off into the vaginal canal. This desquamation goes on constantly and the epithelium is replenished by mitotic division of cells in the basal layer.

Blood Supply and Lymphatic Drainage

Deep lymphatic drainage primarily targets the internal iliac lymph nodes within the pelvis. Lymphatic drainage from the external genitalia primarily courses toward the superficial inguinal lymph nodes. Lymphatic drainage is regionally compartmentalized: the upper third of the vagina drains to external iliac nodes, the middle third to common and internal iliac nodes, and the lower third to the superficial inguinal and perirectal nodes.

Physiological Functions

Sexual Intercourse and Reproduction

During coitus, the vagina receives the penis and ejaculate, which facilitate the ascent of spermatozoa into and through the cervix, up into the uterus and fallopian tubes. The walls of the vagina contain nerve endings that allow women to experience pleasure when aroused and something penetrates it. The vagina expands and becomes lubricated when aroused to prevent friction from feeling painful.

Changes in vaginal blood flow and lubrication are primary components of physiological sexual arousal in women. Sexual arousal, with a strong psychologic and neurologic component, is also closely related to the process of lubrication.

Childbirth

The vagina expands to provide a channel for delivery of a newborn from the uterus. The elastic lamina propria and smooth muscle layers are critical for this distension capacity, and the elastic LP and smooth muscle enable the vagina to distend, particularly during birth.

Menstruation

The vagina is the distal birth canal and serves as an efflux pathway for menstrual blood (menses). The lining of the uterus (endometrium) exits the body through the vagina during menstruation.

Musculature and Smooth Muscle Activity

The muscularis consists of autonomically innervated smooth muscle fibers arranged into an outer longitudinal and inner circular layer. In the basal or sexually quiescent state, the smooth muscle of the vagina is active, especially perimenstrually, when it contracts periodically to expel the uterine/vaginal contents. These vaginal smooth muscle contractions are normally not consciously recognized; they only become obvious if they reach painful, spasmodic levels (dysmenorrheal pain).

The Vaginal Microbiome

Composition and Community State Types

The vaginal microbiome is dominated by Lactobacillus spp., and the depletion of these microorganisms has been associated with adverse conditions that can affect women's health. The most frequently isolated species are Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii, and Lactobacillus iners.

The vaginal microbiota has been previously shown to cluster into community state types (CSTs) that reflect differences in bacterial species composition and abundance. Lactobacillus spp. predominate four of the five CSTs (CST I: L. crispatus; CST II: L. gasseri; CST III: L. iners; CST V: L. jensenii). In contrast, CST IV communities are characterized by a paucity of lactobacilli and the presence of a diverse array of anaerobes such as Gardnerella vaginalis and "Ca. Lachnocurva vaginae".

Protective Mechanisms of Lactobacilli

Production of lactic acid is an essential mechanism by which protective lactobacilli, including L. crispatus, L. gasseri, and L. jensenii, maintain the health of the female lower reproductive tract. Lactic acid decreases the vaginal pH, inhibits the growth of dysbiosis-associated microbes, and interacts with the human immune system to diminish pro-inflammatory responses that could be induced by dysbiosis-associated microbes. Thus, a lower vaginal pH is associated with a higher relative abundance of these Lactobacillus spp. in the vaginal microbiome and lower risks of microbial infections in the female reproductive tract and adverse outcomes in pregnancy, including bacterial vaginosis and preterm birth.

Residing at the port of entry of bacterial and viral pathogens, the vaginal Lactobacillus species can create a barrier against pathogen invasion, since mainly products of their metabolism secreted in the cervicovaginal fluid play an important role in the inhibition of bacterial and viral infections. Therefore, a Lactobacillus-dominated microbiota appears to be a good biomarker for a healthy vaginal ecosystem. This balance can be rapidly altered during processes such as menstruation, sexual activity, pregnancy, and various infections.

Assessment of Vaginal Health

Clinical and Laboratory Assessment

Vaginitis is defined as any condition with symptoms of abnormal vaginal discharge, odor, irritation, itching, or burning. The most common causes of vaginitis are bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis. Diagnosis relies on a combination of clinical and laboratory tools.

Information on the vaginal microbiota can be gathered from the analysis of cervicovaginal fluid by using the Nugent scoring or the Amsel criteria, or at the molecular level by investigating the number and type of Lactobacillus species.

Diagnosis of bacterial vaginosis is commonly made using the Amsel criteria, which include vaginal pH greater than 4.5, positive whiff test, milky discharge, and the presence of clue cells on microscopic examination of vaginal fluid. Bacterial vaginosis is traditionally diagnosed with Amsel criteria, although Gram stain is the diagnostic standard. Newer laboratory tests that detect Gardnerella vaginalis DNA or vaginal fluid sialidase activity have similar sensitivity and specificity to Gram stain.

Bacterial vaginosis can be diagnosed using Amsel criteria, Gram stain, or a nucleic acid amplification test (NAAT). Vulvovaginal candidiasis can be diagnosed by visualization of yeast hyphae or budding yeast on microscopy, vaginal fungal culture, polymerase chain reaction testing, or NAAT. Trichomoniasis can be diagnosed with visualization of motile, flagellated protozoa on saline microscopy, NAAT, or DNA probe test.

Indicators of Normal Vaginal Function

A healthy vaginal environment is characterized by several measurable parameters. Normal vaginal pH in reproductive-age women ranges at or below 4.5, maintained primarily by lactic acid produced by Lactobacillus species. The cells in the vagina are especially responsive to the hormone estrogen, and the body produces higher amounts of estrogen in reproductive years than during menopause. The superficial cells of the epithelium undergo hormone-related cyclical changes such as slight keratinization or increased glycogen production during the menstrual cycle. In the sexually unstimulated state, vaginal fluid has a higher K⁺ and lower Na⁺ concentration compared to plasma throughout the phases of the menstrual cycle.

Conditions and Concerns Associated with the Vagina

Bacterial Vaginosis (BV)

Bacterial vaginosis (BV) is a common clinical syndrome in which the protective lactic acid-producing bacteria (mainly species of the Lactobacillus genus) are supplanted by a diverse array of anaerobic bacteria. Most commonly, this presents clinically with increased vaginal discharge that has a fish-like odor. The discharge itself is typically thin and either gray or white. After being diagnosed with bacterial vaginosis, patients have an increased risk of acquiring sexually transmitted infections (STIs), and pregnant individuals may have an increased risk of early delivery.

Bacterial vaginosis is implicated in 40% to 50% of cases when a cause is identified. Most uncomplicated cases of bacterial vaginosis resolve with treatment; however, recurrences are not uncommon due to the frequent failure of antibiotic treatment to restore the vagina to its typical Lactobacillus-dominant state. Bacterial vaginosis is treated with oral or intravaginal metronidazole or intravaginal clindamycin.

Vulvovaginal Candidiasis (VVC)

Vulvovaginitis most commonly occurs in reproductive-aged women and is caused by several underlying etiologies. Candidiasis is a fungal infection caused by Candida albicans, a polymorphic opportunistic fungus; vulvovaginitis secondary to candidiasis is also known as vaginal candidiasis. Candidal vulvovaginitis is responsible for about one-third of vulvovaginitis occurrences. Typical clinical features include vulvar and vaginal erythema, excoriations, thick white adherent discharge, and swelling. Risk factors such as antibiotic use, estrogen therapy, or pregnancy can be responsible for Candida overgrowth. Vulvovaginal candidiasis is managed with topical or oral antifungals.

Trichomoniasis

Trichomoniasis is a sexually transmitted infection (STI) caused by the parasite Trichomonas vaginalis. It causes cervicitis, vaginitis, and urethritis in women, and urethritis (mostly asymptomatic) in men. Trichomoniasis usually presents with a green or yellow frothy discharge, and speculum examination may reveal cervical erythema with petechiae. Any nitroimidazole drug (e.g., metronidazole) given orally as a single dose or over a longer period resolves 90 percent of trichomoniasis cases.

Vulvovaginal Atrophy (VVA) / Genitourinary Syndrome of Menopause (GSM)

Vulvovaginal atrophy (VVA) and sexual inactivity are prevalent among postmenopausal women. This condition, now more broadly termed genitourinary syndrome of menopause (GSM), results from declining estrogen levels. Vitamin D plays an important role in promoting epithelial cell proliferation, migration, and adhesion. Noninfectious causes of vaginitis include atrophic, irritant, and inflammatory vaginitis.

Noninfectious Vaginitis

Noninfectious causes, including atrophic, irritant, allergic, and inflammatory vaginitis, are less common and account for 5% to 10% of vaginitis cases. There is no cause of vaginitis identified in up to 30% of women. These women may have a range of conditions, including irritant or allergic vaginitis, atrophic vaginitis, or physiologic discharge.

Sexual Dysfunction and Vaginismus

Aberrations of physiologic processes may involve decreased blood flow, as in the clitoral and vaginal vascular insufficiency syndromes. Pelvic muscle weakness or hypertonicity can result in less intense orgasm or vaginismus, respectively. Lack of lubrication and genital atrophy may also interfere with sexual functioning.

Nutrients, Herbs, and Natural Ingredients

Probiotics (Lactobacillus Species)

Traditional Use

The use of fermented dairy foods containing live bacterial cultures, particularly lactobacilli, as health-supporting foods has roots in folk and traditional medicine across many cultures. The specific concept of applying these bacteria to the vaginal tract is a modern clinical development derived from the observation that Lactobacillus-dominated microbiomes characterize healthy vaginal ecosystems.

Scientific Evidence

The dominance of lactobacilli in healthy vaginal microbiota and its depletion in BV has given rise to the concept of oral or vaginal use of probiotic Lactobacillus strains for treatment and prevention of BV. Probiotics, particularly Lactobacillus strains, have been proposed as an alternative or adjunct therapy for bacterial vaginosis and vulvovaginal candidiasis due to their potential to restore a healthy vaginal microbiota.

A 2024 systematic review evaluated 11 randomized controlled trials with a Jadad score greater than three, indicating high-quality studies based on criteria such as randomization, blinding, and dropout rates. The review demonstrated significant improvements in clinical outcomes and vaginal microbiota restoration; however, variability in results highlights the need for further research.

In a double-blind, randomized, placebo-controlled study of vaginal probiotic capsules for recurrent bacterial vaginosis, 120 healthy Chinese women with a history of recurrent BV were assigned randomly to daily vaginal prophylaxis with a capsule containing 8 billion colony-forming units of Lactobacillus rhamnosus, L. acidophilus, and Streptococcus thermophilus or placebo. Probiotic prophylaxis resulted in significantly lower recurrence rates for BV (15.8% vs. 45.0%; P < .001) and Gardnerella vaginalis incidence through 2 months (3.5% vs. 18.3%; P = .02). Between the 2- and 11-month follow-up period, women who received probiotics reported a lower incidence of BV and G. vaginalis.

A 12-week multicenter, randomized, double-blind, placebo-controlled trial (n = 101 reproductive-aged women) evaluated a five-strain probiotic complex (MED-01). MED-01 significantly reduced the Nugent score compared with the placebo. Quantitative PCR analysis confirmed that Lactobacillus plantarum was significantly increased in the vagina, whereas harmful bacteria such as Mobiluncus spp., Gardnerella vaginalis, and Atopobium vaginae were suppressed after 12 weeks.

A systematic review (2024) including 16 RCTs found that Lactobacillus rhamnosus TOM 22.8 (10×10⁹ CFU/day for 10 days) was the most effective strain and dose, significantly improving Nugent scores, vaginal pH, and microbiota composition.

Evidence strength: Moderate. Multiple RCTs support the use of specific Lactobacillus strains for BV prevention and microbiome restoration, but results are heterogeneous across studies, and optimal strains, doses, and routes of administration remain subjects of ongoing research.

Boric Acid

Traditional Use

Boric acid has been used as an antiseptic and home remedy for vaginal infections for over a century, predating modern pharmaceutical antifungals. It was employed empirically in various Western folk medicine contexts as a vaginal wash or suppository.

Scientific Evidence

Boric acid is an antiseptic used as a vaginal medication to treat vaginal infections including yeast infections, bacterial vaginosis, and trichomoniasis. It is administered as a capsule or suppository inserted into the vagina, and is available over the counter, not classified as a pharmaceutical drug.

A systematic review of boric acid for recurrent vulvovaginal candidiasis, found that mycologic cure rates varied from 40% to 100% in patients treated with boric acid; 4 of the 9 included case series reported statistically significant outcomes regarding cure (both mycologic and clinical) rates. None of the included studies reported statistically significant differences in recurrence rates. An average cure rate of 76% was found for vulvovaginal candidiasis boric acid treatment across 41 included studies.

For BV specifically, clinical studies of boric acid for the treatment of bacterial vaginosis are few and evidence is very limited. Based on unpublished data, boric acid by itself has been reported to be inadequate in the initial treatment of acute bacterial vaginosis and is not recommended for this purpose. It is recommended at a dose of 600 mg/day for 2 to 3 weeks for treatment of acute recurrent bacterial vaginosis, and is also suggested at a continuous maintenance dosage of 600 mg two to three times weekly for resistant or recurrent bacterial vaginosis suppression.

Boric acid's antimicrobial activity against anaerobic bacteria, including Gardnerella vaginalis and Atopobium vaginae, disrupts the polymicrobial communities characteristic of bacterial vaginosis. The compound's ability to penetrate and disrupt bacterial biofilms may be particularly important, as these structures contribute to antibiotic resistance and treatment failure in recurrent cases. The restoration of acidic vaginal pH creates an environment favorable for lactobacilli recovery while inhibiting pathogenic bacterial growth.

Regarding the adverse effects caused by boric acid use, vaginal burning sensation (<10% of cases), water discharge during treatment, and vaginal erythema were identified in 7 studies.

Evidence strength: Moderate for recurrent VVC (non-albicans species and azole-resistant infections); weak and very limited for BV. No large, high-quality placebo-controlled RCTs have yet established boric acid as a primary first-line treatment for either condition. Evidence for trichomoniasis is anecdotal.

Vitamin D

Traditional Use

Vitamin D has not historically been used in traditional medicine specifically for vaginal health. Its role in vaginal physiology is an area of modern scientific investigation arising from the discovery of vitamin D receptors in urogenital tissues.

Scientific Evidence

Vitamin D receptors (VDRs) have been identified as a major contributor to its effects, and it is now well known that VDRs are expressed in the superficial layers of the urogenital organs. Numerous clinical studies have observed improvements in vulvovaginal symptoms linked to the genitourinary syndrome of menopause (GSM) with vitamin D supplementation. These studies have reported positive effects on various aspects such as vaginal pH, dryness, sexual functioning, reduced libido, and decreased urinary tract infections.

A double-blind clinical trial (n = 44 postmenopausal women) examined daily intravaginal vitamin D suppositories for 8 weeks. In the treatment group, the number of superficial cells increased significantly and vaginal pH decreased significantly compared to the control group after 56 days. The mean pain significantly reduced after 8 weeks in the treatment group compared to the control group (P < 0.001). The clinical trial showed that vitamin D vaginal suppositories have protective effects that decrease the mean pain during intercourse, vaginal pH, dryness, and paleness and help increase the vaginal maturation value compared to the placebo suppositories.

By contrast, a double-blinded, randomized, placebo-controlled trial (n = 80) of oral vitamin D (ergocalciferol 40,000 IU per week for 12 weeks) found discordant results: in an intention-to-treat analysis, VMI, vaginal pH, and VAS of VVA symptoms showed no significant differences between both groups at six and 12 weeks; however, the mean difference of VMI in the vitamin D group between baseline and at six weeks showed significant improvement.

A 2025 systematic review and meta-analysis in the International Journal of Gynecology & Obstetrics found that topical vitamin D showed improvement in the vaginal maturation index (VMI) and the arousal subscale of the female sexual function index (FSFI). Oral VD had no significant improvement across measured outcomes.

Evidence strength: Preliminary to moderate. Topical (intravaginal) vitamin D appears more consistently beneficial for postmenopausal VVA than oral supplementation, but studies are generally small and heterogeneous. Larger, adequately powered RCTs are needed.

Garlic (Allium sativum)

Traditional Use

Garlic has a long history of use across multiple traditional medicine systems — including Ayurvedic, Mediterranean folk, and traditional Chinese medicine — as a broad-spectrum antimicrobial agent. Its use for vaginal infections, including insertion of raw cloves as suppositories, has been documented in folk medicine traditions, though this practice is neither endorsed nor supported by established herbalism authorities.

Scientific Evidence

Garlic has antifungal properties and can be used in the treatment of fungal infections such as vaginal yeast infections. According to a systematic review of studies, garlic extract and garlic oil showed inhibitory effects on Candida species. However, the evidence base is largely preclinical. Garlic contains a compound called allicin that has antifungal properties, but minimal research has directly investigated garlic's topical use for vaginal yeast infections, and studies have been limited and largely inconclusive.

While garlic contains allicin, a compound with antimicrobial properties, its effectiveness in treating vaginal infections lacks robust clinical evidence. A Harvard Medical School gynecologist is quoted noting that it is true that a compound in garlic, allicin, has been shown to kill yeast in a laboratory, but you cannot put enough cloves of garlic in your vagina — or take enough oral garlic capsules — to achieve the same effect.

Evidence strength: Preclinical and very weak. In vitro activity of garlic/allicin against Candida has been demonstrated, but there are no adequately designed human clinical trials supporting garlic as a treatment for vaginal infections. Direct vaginal application of raw garlic is not supported by evidence and carries irritation risk.

Tea Tree Oil (Melaleuca alternifolia)

Traditional Use

Tea tree oil has been used historically in Australian Aboriginal medicine and was later adopted in 20th-century Western folk and alternative medicine for its purported broad-spectrum antimicrobial activity. Its use for vaginal infections — typically as a diluted topical application — has been documented in alternative health literature.

Scientific Evidence

Tea tree oil contains properties that may help fight against a wide range of viruses, bacteria, and fungi, including yeast. Research indicates tea tree oil is effective in helping treat Candida yeast; however, researchers caution against taking tea tree oil orally and suggest it only as a topical remedy to avoid toxicity. Tea tree oil can also cause skin irritation and an allergic reaction.

Tea tree oil has no demonstrated benefit and can cause irritation in vaginal application, according to a review from Harvard Medical School's Department of Obstetrics, Gynecology, and Reproductive Biology.

Evidence strength: Largely in vitro/preclinical. While laboratory studies demonstrate antifungal activity against Candida species, clinical human trials of intravaginal tea tree oil use for vaginal infections are absent or inadequate. The irritation and sensitization potential further limits its applicability.

Summary Table of Evidence Strength

• Probiotics (Lactobacillus species): Moderate — supported by multiple RCTs for BV prevention and microbiome restoration; strain and dose specificity important; variability across studies.
• Boric acid (intravaginal): Moderate for recurrent/azole-resistant VVC; weak for BV; no high-quality RCT for primary treatment of acute infections.
• Vitamin D (topical/intravaginal): Preliminary to moderate for postmenopausal VVA; oral route shows inconsistent benefit; small trial sizes limit conclusions.
• Garlic / allicin: Preclinical only — in vitro antifungal activity; no clinical trial evidence for vaginal use.
• Tea tree oil: Preclinical only — in vitro antifungal activity; no validated clinical human trial; irritation risk noted.

References

• Gold JM, Shrimanker I. Physiology, Vaginal Structure and Function. StatPearls [Internet]. NCBI Bookshelf. Updated 2023 Jul 24.
• Anatomy, Abdomen and Pelvis: Female External Genitalia. StatPearls [Internet]. NCBI Bookshelf.
• Anatomy, Abdomen and Pelvis: Bartholin Gland. StatPearls [Internet]. NCBI Bookshelf. Updated 2024.
• Anatomy, Abdomen and Pelvis: Pelvic Floor. StatPearls [Internet]. NCBI Bookshelf.
• Bacterial Vaginosis. StatPearls [Internet]. NCBI Bookshelf.
• Vaginal Candidiasis. StatPearls [Internet]. NCBI Bookshelf.
• Petrova MI, et al. Lactobacillus species as biomarkers and agents that can promote various aspects of vaginal health. Front Physiol. 2015;6:81. PMC.
• Vaginal microbiota and the potential of Lactobacillus derivatives in maintaining vaginal health. PMC.
• Vaginal microbioma and the presence of Lactobacillus spp. as interferences in female fertility: A review system. PMC.
• Brotman RM. Vaginal microbiome and sexually transmitted infections: an epidemiologic perspective. J Clin Invest. 2011;121(12):4610–7. PubMed.
• Holm JB, et al. Integrating compositional and functional content to describe vaginal microbiomes in health and disease. Microbiome. 2024;12(1):21. PubMed.
• Park SH, et al. Efficacy and Safety of MED-01 Probiotics on Vaginal Health: A 12-Week, Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Nutrients. 2023;15(2):331. PMC.
• Probiotics for the Prevention of Vaginal Infections: A Systematic Review. PMC. 2024.
• Effective probiotic regimens for bacterial vaginosis treatment and recurrence prevention: A systematic review. PMC. 2025.
• Chai B, et al. Efficacy of vaginal probiotic capsules for recurrent bacterial vaginosis: a double-blind, randomized, placebo-controlled study. Am J Obstet Gynecol. 2010. PubMed.
• Bacterial vaginosis: a review on clinical trials with probiotics. PubMed. 2013.
• Effects of probiotics on the recurrence of bacterial vaginosis: a review. PubMed. 2013.
• Iavazzo C, et al. Boric acid for recurrent vulvovaginal candidiasis: the clinical evidence. J Womens Health (Larchmt). 2011;20(8):1245–55. PubMed.
• Lærkeholm Müller et al. Boric Acid for the Treatment of Vaginitis: New Possibilities Using an Old Anti-Infective Agent: A Systematic Review. Dermatologic Therapy. 2024.
• Intravaginal boric acid treatment for recurrent bacterial vaginosis: short-term effects on vaginal health parameters and patient satisfaction. PMC. 2025.
• Therapeutic Effects of Vitamin D on Vaginal, Sexual, and Urological Functions in Postmenopausal Women. Nutrients. 2023;15(17):3804. PMC.
• The effect of vitamin D on vaginal atrophy in postmenopausal women. PMC.
• Effect of Vitamin D Supplement on Vulvovaginal Atrophy of the Menopause. Nutrients. 2020;12(9):2876. PMC.
• Youssef et al. The effectiveness of vitamin D as an alternative to FDA-approved treatment and other therapies for managing vulvovaginal atrophy and sexual inactivity in postmenopausal women. A systematic review and meta-analysis. Int J Gynecol Obstet. 2025.
• Therapeutic effects of garlic (Allium sativum) on female reproductive system: A systematic review. ScienceDirect/Heliyon. 2023.
• An Evidence-Based Review of Medicinal Plants Used for the Treatment of Vaginitis by Avicenna in "the Canon of Medicine". PMC.
• Vaginitis: Diagnosis and Treatment. American Academy of Family Physicians (AAFP). 2025.
• Vaginitis. PubMed. Am Fam Physician. 2011.
• Physiologic Measures of Sexual Function in Women: A Review. PMC.
• The vaginal epithelium. Vulvovaginal Disorders. Annotation O.
• Female Genital Anatomy. Boston University School of Medicine, Sexual Medicine Program.