The Number That Runs Everything

pH is a measure of acidity or alkalinity on a scale of o to 14, with 7 being neutral. The vaginal environment maintains a pH of approximately 3.8 to 4.5: slightly acidic, by design. This acidity supports the beneficial bacteria that protect against infection. When it shifts, even modestly, the conditions change.

Why your detergent is working against you
Most household laundry detergents sit at a pH of 9 to 11. When underwear washed in these products is worn against the body’s most sensitive skin, the residual alkalinity can gradually disrupt the local pH environment.

The effect is not always immediate or dramatic. It often presents as low-level, recurring irritation with no obvious cause.

Where Yiah sits
Yiah is formulated at a pH of 5.5: the same benchmark used by dermatologist-recommended intimate washes. It is skin-safe, gentle, and meaningfully less disruptive than anything formulated for general laundry. A pH of 5.5 supports the skin barrier without overriding the body’s own chemistry.

What else affects vaginal pH

Menstruation: blood has a higher pH, which temporarily shifts the vaginal
environment.
Semen: also alkaline, which is why some people notice changes after unprotected sex.
Antibiotics: disrupt the Lactobacillus bacteria that maintain acidity.
Hormonal changes: pregnancy, perimenopause, and hormonal contraception all influence pH.
Certain cleansing products: anything with a high pH or harsh surfactants.

Signs your pH may be off

• Unusual or persistent odour
• Discharge that has changed in colour or consistency
• Itching or general irritation without an obvious cause
• These are signals, not diagnoses. A healthcare provider can confirm what is happening with a simple test.
• What you can control is what you expose the environment to daily.