The term sexually transmitted disease STD is used to refer to a condition passed from one person to another through sexual contact. Depending on the specific STD, infections may also be transmitted through sharing needles and breastfeeding. But some STDs cause obvious symptoms. In men, common symptoms include:. Specific symptoms can vary, depending on the STD. Learn more about the symptoms of STDs in men.

Sexually transmitted infections STIs are infectious diseases spread through sexual contact. The best way to prevent your teen from contracting an STI is to advise them to not have any type of sexual contact with another person. But if they decide to be sexually active, or are currently sexually active, there are several safety measures to follow. These are advised by experts to help reduce your teen's risk of getting an STI. They include:.

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Sexually transmitted diseases STDs are infections that are passed from one person to another through sexual contact. The causes of STDs are bacteria, parasites, and viruses. There are more than 20 types of STDs, including. Most STDs affect both men and women, but in many cases the health problems they cause can be more severe for women. If a pregnant woman has an STD, it can cause serious health problems for the baby.