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Home > Health Library > Sexually Transmitted Infections
Aside from colds and the flu, sexually transmitted infections (STIs) are some of the most widespread infections both in the United States and the world. STIs affect both men and women, and almost half of all STIs occur in people younger than 25 years old. Exposure to an STI can occur any time you have sexual contact with anyone that involves the genitals, the mouth (oral), or the rectum (anal). Exposure is more likely if you have more than one sex partner or do not use condoms. Some STIs can be passed by nonsexual contact, such as by sharing needles or during the delivery of a baby or during breastfeeding. Sexually transmitted infections (STIs) are also called sexually transmitted diseases (STDs).
STIs are a worldwide public health concern because there is more opportunity for STIs to be spread as more people travel and engage in sexual activities. Some STIs have been linked to an increased risk of certain cancers and infection with human immunodeficiency virus (HIV). Pregnant women can spread STIs to their babies. Many people may not have symptoms of an STI but are still able to spread an infection. STI testing can help find problems early on so that treatment can begin if needed. It is important to practice safer sex with all partners, especially if you or they have high-risk sexual behaviors. See the Prevention section of this topic.
If you think you may have symptoms of an STI:
There are at least 20 different STIs. They can be caused by viruses, bacteria, and protozoa. Some of the most common STIs in the U.S. are:
Bacterial STIs can be treated and cured, but STIs caused by viruses usually cannot be cured. You can get a bacterial STI over and over again, even if it is one that you were treated for and cured of in the past.
It is important to seek treatment if you think you may have an STI or have been exposed to an STI. Most health departments, family planning clinics, and STI clinics provide confidential services for the diagnosis and treatment of STIs. Early treatment can cure a bacterial STI and prevent complications.
If you are a parent of a teenager, there are many resources available, such as your health professional or family planning clinics, to help you talk with your teen about safer sex, preventing STIs, and being evaluated and treated for STIs.
In women, STIs can cause a serious infection of the uterus and fallopian tubes (reproductive organs) called pelvic inflammatory disease (PID). PID may cause scar tissue that blocks the fallopian tubes, leading to infertility, ectopic pregnancy, pelvic abscess, or chronic pelvic pain.
STIs in pregnant women may cause problems such as:
Any child or vulnerable adult with symptoms of an STI needs to be evaluated by a health professional to determine the cause and to assess for possible sexual abuse.
If you have symptoms of an STI or have been exposed to an STI whether by oral, anal, or vaginal sexual activity, check your symptoms to decide if and when you should see a doctor.
Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
In females, symptoms of an STI (sexually transmitted infection) may include:
In males, symptoms of an STI (sexually transmitted infection) may include:
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
Home treatment is never an appropriate treatment for a sexually transmitted infection (STI). Evaluation by a health professional is needed for:
Symptoms of STIs may not appear for many days, weeks, months, or, with HIV, even years after an exposure. After you have been exposed to an STI, you cannot reduce the risk you now have of getting an infection.
A regular habit of genital self-examination once a month will help you know what is normal for you and when you may have symptoms of an STI.
In addition to your health professional, there are other resources that can help you with information about STI evaluation and treatment. These resources include:
Treatment for pregnant women is monitored by their health professional to avoid complications. STIs in pregnant women may cause problems such as:
It is important for you and an infected partner to complete all medical treatment for an STI to prevent the infection from returning. You may need to be rechecked after treatment is complete.
Call your doctor if symptoms persist or become more severe or frequent.
Home test kits for some STIs are available but it is recommended that you consult your health professional about any STI symptoms.
You can take measures to reduce your risk of becoming infected with a sexually transmitted infection (STI). You can also reduce the risk of transmitting an STI to your sex partner.
Delay sexual activity until you are prepared both physically and emotionally to have sex. Nearly two-thirds of all STIs occur in people younger than 25 years old. Sexually active teenagers are at high risk for STIs because they frequently have unprotected sex and have multiple partners. Biological changes during the teen years also may increase their risk for getting an STI.
Make sure your immunizations are up-to-date. You can get a hepatitis A, hepatitis B, and HPV vaccine to prevent these infections. The HPV (human papillomavirus) vaccine protects against HPV. There are many types of HPV. Some types of the virus can cause genital warts. Other types can cause cervical or oral cancer and some uncommon cancers, such as vaginal and anal cancer. The HPV vaccine protects against the most common HPV types that can cause serious problems. For more information, see the topic Immunizations.
STIs are a concern worldwide. It is important to practice safer sex with all partners, especially if you or they may have high-risk sexual behaviors.
It is especially important that pregnant women who are at risk for STIs practice safer sex because an STI can affect their baby (fetus). An STI may threaten the life of your baby or cause serious long-term problems or disabilities for your baby.
Preventing a sexually transmitted infection (STI) is easier than treating an infection after it occurs.
Condoms can protect you against sexually transmitted infections (STIs). Even if you are protected against pregnancy by birth control pills or another method, use a condom to prevent STIs.
Using condoms reduces the risk of becoming infected with most STIs, especially if the condoms are used correctly and consistently. Condoms must be put on before beginning any sexual contact or activity. Use condoms with a new partner until you are certain he or she does not have an STI.
Condoms are made of latex (rubber), polyurethane, or sheep intestine. Latex and polyurethane condoms help prevent the spread of sexually transmitted infections (STIs) such as HIV, but sheep intestine condoms do not.
Even if you are using another birth control method to prevent pregnancy, you may wish to use condoms to reduce your risk of getting an STI. Female condoms are available for women whose partners do not have or will not use a male condom.
Condoms do not prevent skin-to-sore contact in the genital area, so it is possible to spread an STI with genital contact. It is important to have any symptoms in the genital area evaluated.
Mouth barriers, such as a dental dam, can be used to reduce the spread of infection through oral sexual activity. You can discuss this with your dentist or health professional.
Avoid douching if you are a woman, because it can change the normal balance of organisms in the vagina and increases the risk of getting an STI.
Most spermicides contain a chemical called nonoxynol-9 (N9). The U.S. Food and Drug Administration (FDA) warns that N9 in vaginal contraceptives and spermicides may irritate the lining of the vagina or rectum. This may increase the risk of getting HIV from an infected partner.
So although using a spermicide with a condom is more effective for birth control, using a spermicide may increase your risk for getting HIV.
To prepare for your appointment, see the topicMaking the Most of Your Appointment.
You can help your health professional diagnose and treat your condition by being prepared for your appointment.
Current as of:
July 1, 2021
Author: Healthwise StaffMedical Review: William H. Blahd Jr. MD, FACEP - Emergency MedicineKathleen Romito MD - Family MedicineAdam Husney MD - Family Medicine
Current as of: July 1, 2021
Author: Healthwise Staff
Medical Review:William H. Blahd Jr. MD, FACEP - Emergency Medicine & Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine
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