Inclusion criteria
Participants must meet all the following criteria:
* Healthy women with a vagina 21 - 60 years old at the time of electronic consent
* Sex assigned female at birth
* Eligible menstrual status:
* Pre-menopausal is defined as women in their childbearing years who must have a regular menstrual cycle (consistently average cycle length of 21 to 35 days) Note: Women in their childbearing years who do not have a regular menstrual cycle due to a hormone-based intrauterine device are eligible
* Peri-menopausal is defined as women who report irregular periods (differences in menstruation compared with their typical cycle in their 20s), with at least 1 period in the last 12 months AND report mild menopausal symptoms (e.g., vasomotor symptoms such as hot flashes, night sweats)
* Post-menopausal is defined as women with an absence of menstrual cycle for the last 12 consecutive months or longer
* Willing to ingest an oral capsule during the study and be blinded to product identity (active or placebo)
* Willing to self-collect vaginal swabs and pH samples
* Willing to abstain from the use of intravaginal products during the study period (e.g., vaginal suppositories, vaginal moisturizers including hyaluronic acid, boric acid suppositories, pH balancing wipes, douching, vaginal creams/gels), as well as lubrication and spermicides
* Able to read and comprehend English and provide electronic informed consent
* Resides in the United States
Exclusion criteria
* Active vaginal, pelvic, or urogenital infection (e.g., UTI, BV, yeast infection)
* Chronic vulvar and vaginal conditions (e.g., vulvodynia, lichen sclerosis and lichen planus, desquamative inflammatory vaginitis)
* Unexplained vaginal bleeding
* Use of copper-based intrauterine devices
* Note: Hormone-based intrauterine devices are permitted (e.g., Mirena®)
* For peri-menopausal and post-menopausal individuals, use of estrogen-based vaginal cream/gel or suppositories
* Women who have undergone surgical menopause (e.g., bilateral oophorectomy with or without hysterectomy)
* Current or recent use (\< 3 months prior to enrollment) of antibiotics or antifungals, or anticipated use during study period (e.g., perioperative antibiotics for upcoming elective procedures)
* Current or recent use (\<4 weeks prior to enrollment) of any other probiotic, prebiotic or synbiotic-containing products
* Note: Individuals who undergo a washout of 4-weeks prior to enrollment and are willing to abstain from consuming such products during the study are permitted. Food-based probiotics, prebiotics, and synbiotics are permitted (e.g., kimchi, yoghurt, kefir, kombucha)
* Pregnant, breastfeeding, or actively trying to conceive during the study period.
* Allergy to any ingredients in the investigational or placebo product.
* Receiving chronic oral steroid therapy (excluding those for skin, eyes, nose, or inhaled) or have received such treatment within 4 weeks of enrollment
* Surgery, immunotherapy, chemotherapy, radiation, or biological cancer therapy within 4 weeks of enrollment and/or planned during the next 2 weeks
* Diagnosed and active serious medical condition requiring current treatment (e.g., cancer; autoimmune diseases \[lupus, rheumatoid arthritis, Crohn's disease\]; serious cardiac, liver, endocrine (insulin-dependent diabetes and/or on SGLT2 inhibitors such as Jardiance®/Empagliflozin, Farxiga®/Dapagliflozin) or kidney disease; psychiatric conditions / substance use disorders; chronic infections \[HIV, Hepatitis B/C\], any condition which in the investigator's opinion may jeopardize the individual's safety or interfere with the ability to comply with the study
* Participation in another clinical trial within 90 days of screening
* International travel during the study period
