When the solid has a high affinity for water - in which case it is called hydrophilic (high energy e.g. glass)- water spreads. In the opposite case of hydrophobic (low energy e.g. teflon) surfaces, water does not spread but, instead, forms at equilibrium a spherical cap resting on the substrate with a 'contact angle'.
Infections such as trichomoniasis, gonorrhea, and Chlamydia (all STDs); and yeast infection can all cause vaginal discharge. Vaginal discharge can be associated with other symptoms such as burning or itching. Antibiotics are given for infections that cause vaginal discharge.
Sexually transmitted diseases -- or STDs -- often are silent, meaning there are no symptoms. Women may not notice any symptoms until they have developed serious complications. Be on the lookout for: 1  A drip or discharge from the penis, urethra, vagina, or anus; the color may be white, yellow, green, or gray.