Menstrual Cycle Hormone Fluctuations & Vulvovaginal Health
Recurring vulvovaginal symptoms such as itching, burning, and abnormal discharge often follow a monthly pattern. Bacterial vaginosis (BV), aerobic vaginitis (AV), cytolytic vaginosis (CV), and recurrent vulvovaginal candidiasis (RVVC) commonly flare in response to hormonal shifts during the menstrual cycle, so understanding how these hormonal changes affect the vaginal microbiome can help explain symptom patterns and support more effective treatment strategies.
Hormones and the Vaginal Microbiome
Oestrogen plays a key role in maintaining vaginal health by supporting the growth of Lactobacillus bacteria—beneficial microbes that produce lactic acid and help maintain a low vaginal pH, creating a protective environment against harmful microorganisms.
Oestrogen levels are lowest during the late luteal and early follicular phases of the menstrual cycle. These changes can reduce Lactobacillus activity, raise vaginal pH, and increase the risk of BV and AV flares.
Around ovulation, oestrogen peaks. While this encourages Lactobacillus growth, high oestrogen levels may also promote Candida albicans activity by enhancing its ability to adhere to vaginal tissue and shift into its more invasive hyphal form—contributing to RVVC flares in susceptible individuals. (Nb. there are other yeast species that can cause RVVC, but Candida albicans is the most common.)
Menstrual blood, which is more alkaline than normal vaginal pH, can temporarily raise pH and encourage the growth of opportunistic bacteria such as those responsible for BV & AV. Those with prolonged periods may be even more vulnerable due to extended exposure to this higher pH state.
Identifying Patterns Through Tracking & Testing
Cycle tracking for specific symptoms in relation to the menstrual cycle can provide valuable insights and guide targeted treatment or prevention. Vaginal pH testing may help identify high-risk times for flare-ups, allowing for proactive preventative approaches. It’s always essential to speak with your GP or local sexual health clinic if you experience new or recurrent vulvovaginal symptoms to ensure thorough evaluation and care. Functional testing such as vaginal microbiome analysis can additionally provide insight into specific microbial patterns and influences on symptom occurrence, and are best utilised when symptoms occur.
A Whole-Person Approach to Recurring Symptoms
Recurrent vulvovaginal symptoms are rarely caused by just one factor. Hormonal balance, nutrition, stress, tissue integrity, partner health, microbiome balance, and immune function can all play a role and are essential to assess in a thorough case history. While this list may seem a little overwhelming, not everything requires a supplement or a herb, nor does everything need to be treated in everyone! Foundational diet and lifestyle changes are impactful initial steps in a personalised care plan that can support multiple systems, in addition the judicious use of specific supplemental approaches.
Individualised Support Can Make a Difference
You don’t have to live with recurring discomfort—support is available, and you deserve personalised, comprehensive care.
References
Chaban, B., Links, M.G., et al. (2014). Characterization of the vaginal microbiota of healthy Canadian women through the menstrual cycle. Microbiome, 2(1), 23. https://doi.org/10.1186/2049-2618-2-23
Gonçalves, B., Ferreira, C., et al. (2016). Vulvovaginal candidiasis: Epidemiology, microbiology and risk factors. Critical Reviews in Microbiology, 42(6), 905–927. https://doi.org/10.3109/1040841X.2015.1091805
Mendling, W. (2016). Basics of the vaginal microbiome and clinical practice. Geburtshilfe und Frauenheilkunde, 76(12), 1219–1228. https://doi.org/10.1055/s-0042-117294
Ma, B., Forney, L.J., & Ravel, J. (2012). Vaginal microbiome: Rethinking health and disease. Annual Review of Microbiology, 66, 371–389. https://doi.org/10.1146/annurev-micro-092611-150157
