Definition – What is bacterial vaginosis?
Bacterial vaginosis is an overpopulation of the vagina with so-called pathogenic germs. These germs are partly found in the vaginal flora and are partly transmitted during sexual intercourse. If the natural vaginal flora is imbalanced to the detriment of the important lactic acid bacteria of the vagina, other germs can colonise more easily. This imbalance changes the pH value of the vagina. This is an important criterion for bacterial vaginosis.
Associated symptoms
Many women do not notice bacterial vaginosis at all because it does not necessarily cause symptoms. However, if symptoms are present, a change in vaginal discharge is almost always observed. The discharge is typically thin or foamy and greyish-white to yellow.
An unpleasant, fishy odor is also very characteristic of bacterial vaginosis. The odour is caused by the breakdown of proteins by the bacteria. Other symptoms are rather rare, but can be present.
These include burning, vaginal pain during sexual intercourse, known as dyspareunia. Burning when urinating and vaginal itching are also possible. General symptoms such as fever and lower abdominal pain are more likely to indicate an ascending infection, such as uterine or ovarian inflammation. However, they are not typical for bacterial vaginosis.
Causes – How does bacterial vaginosis develop?
The causes of bacterial vaginosis are not fully understood, but there are some mechanisms that promote its development. First of all, it is therefore important to understand how the healthy vaginal flora functions. The natural vaginal flora contains the so-called bacteria.
These are lactic acid bacteria that are responsible for the acidic pH of the vagina. The acidic pH value protects the vagina against ascending infections. Various factors, such as frequent sexual intercourse, incorrect or excessive intimate hygiene, antibiotic therapy and the introduction of foreign bodies (e.g. sex toys) can change the vaginal flora.
Although frequent sex and frequently changing sexual partners are among the risk factors for bacterial vaginosis, it is not a sexually transmitted disease in the conventional sense. Rather, changes in the vaginal milieu lead to a multiple multiplication of germs already present in the vagina or of germs that have settled temporarily. The balance is then not on the side of the natural flora, but on the side of the pathogenic germs.
In bacterial vaginosis, an imbalance in the bacterial colonisation of the vagina leads to unpleasant symptoms such as itching and burning. Various pathogens are involved in this clinical picture. These are pathogens that are present in the vagina anyway, or pathogens that only colonise the vagina temporarily.
Probably the most common germ that causes bacterial vaginosis is the bacterium Gardnerella vaginalis. This rod bacterium belongs to the natural vaginal flora. If the balance is disturbed, Gardnerella vaginalis increases a hundredfold and leads to discomfort.
Apart from this bacterium, several other pathogens are also found in bacterial vaginosis, such as Mobiluncus or Prevotella. However, the number of bacteria, which are very important for healthy vaginal flora, decreases. The exact causes for the occurrence – especially for the repeated occurrence – of bacterial vaginosis are not yet fully understood.
However, there are a number of risk factors that can promote bacterial vaginosis. Frequently changing sexual partners and frequent, especially unprotected, sexual intercourse are important risk factors. However, sexual contact does not lead to the transmission of a germ causing the disease, but seems to lead to an imbalance in the vaginal flora in a different way.
Other risk factors are frequent vaginal rinsing and the use of cosmetic products in the intimate area. Stress and a low social status also seem to be associated with an increased incidence of bacterial vaginosis. In addition, bacterial vaginosis occurs more frequently after systemic antibiotic therapy.
Antibiotic therapy can cause a change in the vaginal flora as an undesirable side effect. This makes it easier for germs such as garnderella vaginalis to multiply uncontrollably. An oestrogen deficiency, such as that which occurs during menopause or puerperium, is also a risk factor for bacterial vaginosis.
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