Why Your Vaginal Microbiome
Changes After 45

The vaginal microbiome is unlike any other in the body. Where the gut thrives on diversity, the vagina is healthiest when it is dominated — almost exclusively — by a single genus: Lactobacillus. These bacteria produce lactic acid, keeping vaginal pH between 3.8 and 4.5, a level that is hostile to pathogens and protective of sensitive tissue.

For most of a woman's reproductive years, oestrogen maintains this environment by stimulating vaginal epithelial cells to store glycogen. Lactobacillus feeds on glycogen, producing the lactic acid that defines a healthy vaginal microbiome. The system is self-sustaining — as long as oestrogen is present.

What Actually Happens

As oestrogen falls during perimenopause, glycogen stores in vaginal cells decline. Lactobacillus populations — particularly the dominant and most protective strain, L. crispatus — begin to thin. pH rises toward neutral. The barrier that has protected vaginal tissue for decades weakens.

The result is a shift microbiologists call dysbiosis: the absence of Lactobacillus dominance, and the rise of opportunistic bacteria and fungi that would previously have been crowded out. This manifests as dryness, recurring discomfort, altered odour, and — for many women — a loss of the intimate confidence they have always known.

Can It Be Reversed?

The decline is not irreversible. Targeted supplementation with specific Lactobacillus strains — ones clinically studied in the vaginal environment, not just the gut — can replenish what hormonal change depletes. The key is strain specificity: generic probiotic supplements are formulated for the gut and do not reliably colonise vaginal tissue.

FloraGuard contains four strains selected precisely for their activity in the vaginal microbiome: L. crispatus, L. rhamnosus, L. reuteri, and L. acidophilus. Each has documented mechanisms in the vaginal environment, and together they address the full range of what oestrogen decline disrupts.