What is pH?


You may sometimes wonder about the ideal pH of an intimate hygiene solution: “Which pH values should I choose? Alkaline? Neutral? Acidic?” As this is something we are often asked, we wanted to clearly answer all your questions, with the help of experts.

What is pH? 

neutral pH, acidic pH, physiological pH: what do they mean?

The pH (potential hydrogen) is a unit that measures the acidity or alkalinity of a solution or medium.

The pH varies from 1 to 14:

  • under 7: it is acidic
  • 7 is neutral
  • above 7: it is alkaline or basic
  • pH scale

The physiological pH is the normal pH of an area of the body. When we say that a product has a physiological pH, this means the pH of the product is close to the area where it is applied.

What pH should you choose for a personal hygiene solution?

The intimate genital area is composed of 2 distinct areas, each with its own particularities: the internal vaginal area and the external vulvo-anal area.

The internal area: the vaginal cavity 

The pH in the personal hygiene product has no impact on the vaginal acidic pH as:

  • The vaginal cavity has its own system for maintaining acidity.
  • The personal hygiene product is also applied externally, which limits its interaction with the vaginal cavity.
  • The external area, consisting of the vulval and peri-anal areas
  • The average physiological pH is between 4.8 and 8, depending on whether it is measured in the mucosa or the skin. Like the rest of the body, this area has its own regulation system which maintains the pH at its physiological level.

Jean-Marc BOHBOT

Infectologist/Medical Director, Fournier Institute

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