Trichomoniasis
Condition
Definition
Trichomoniasis is a sexually transmitted infection (STI).
Causes
Trichomoniasis is caused by a parasite. An infected person can pass it on to his or her partner during sex.
Risk Factors
Trichomoniasis is more common in women. The risk may be higher for those who:
- Have more than one sex partner
- Do not use condoms during sex
- Have had STIs before
Symptoms
Some people may not have symptoms of trichomoniasis. Others may have:
In women:
- A bad-smelling, greenish-yellow discharge from the vagina
- Pain, itching, or burning of the genitals
- Bleeding after sex
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In men:
- Discharge from the penis
- Itching or pain
- Pain when passing urine
- Pain in the testes or scrotum
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Diagnosis
The doctor will ask about symptoms and health history. You will also be asked about your sexual history. A physical exam will be done. A pelvic exam may also be done.
Tests will be done to look for signs of infection, such as:
- Women—testing fluid or discharge from the vagina
- Men—testing urine, semen, or discharge from the penis
Treatment
The infection is treated with antibiotics. Sex partners may also need treatment.
Prevention
The risk of trichomoniasis may be lowered by:
- Always using condoms during sex
- Only having sex with one person who does not have an STI
The American Congress of Obstetrics and Gynecology
Centers for Disease Control and Prevention
CANADIAN RESOURCES:
Sex & U—The Society of Obstetricians and Gynaecologists of Canada
The Sex Information & Education Council of Canada
The American Congress of Obstetrics and Gynecology
Centers for Disease Control and Prevention
CANADIAN RESOURCES:
Sex & U—The Society of Obstetricians and Gynaecologists of Canada
The Sex Information & Education Council of Canada
References
- Mercer F, Johnson PJ. Trichomonas vaginalis: pathogenesis, symbiont interactions, and host cell immune responses. Trends Parasitol. 2018;34(8):683-693.
- Sexually transmitted diseases. National Institute of Allergy and Infectious Diseases website. Available at: https://www.niaid.nih.gov/diseases-conditions/sexually-transmitted-diseases.
- Trichomoniasis. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/std/trichomonas/STDFact-Trichomoniasis.htm.
- Trichomoniasis. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/trichomoniasis.
Contributors
- David L. Horn, MD, FACP
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