Trichomoniasis Clinical Presentation

Updated: Feb 02, 2022
  • Author: Darvin Scott Smith, MD, MSc, DTM&H, FIDSA; Chief Editor: Michael Stuart Bronze, MD  more...
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T vaginalis transmission occurs predominantly via sexual intercourse, so it is typically found in sexually active individuals. The organism is most commonly isolated from vaginal secretions in women and urethral secretions in men. Rectal prevalence of T vaginalis among men who have sex with men appears low. [9] Although T vaginalis has not been isolated from oral sites, evidence suggests that it may cause a sexually transmitted oral infection in rare cases. [17] T vaginalis is also transmitted vertically [58] and can be asymptomatic for long durations. Nearly half of infected females and nearly all infected males are asymptomatic. [22, 59] One third of asymptomatic women become symptomatic within 6 months. [22] Because of this, a lack of sexual history should not be used to rule out T vaginalis infection as a possible diagnosis.


Trichomoniasis symptoms in women range from none to severe pelvic inflammatory disease (PID). Women with trichomoniasis frequently report an abnormal vaginal discharge, which may be purulent, frothy, or bloody. Although frothy vaginal discharge is thought to be the classic presentation of trichomoniasis, women with trichomoniasis also commonly report the following: [16, 60]

  • Abnormal vaginal odor (often described as musty)
  • Vulvovaginal itching, burning, or soreness
  • Dyspareunia (pain during sexual intercourse), often the major complaint
  • Dysuria (pain during urination)
  • Postcoital bleeding
  • Lower abdominal pain

In addition to its associated signs and symptoms, trichomoniasis may lead to cervicitis. This is characterized by 2 major signs, as follows: [57]

  • Purulent discharge in the endocervical canal
  • Easily induced endocervical bleeding

T vaginalis infection is also one of the top 3 causes of vaginitis. [57] Vaginitis is usually characterized by vaginal discharge presenting with any of the following:

  • Vulvar itching
  • Irritation
  • Odor

The two other most common causes of vaginal discharge are anaerobic bacterial overgrowth of normal flora and candidiasis (infection with Candida albicans). [57]


Men with trichomoniasis may be asymptomatic, may have mild symptoms, or may experience acute trichomoniasis. Men with trichomoniasis are more likely than women to be asymptomatic and tend to have much faster natural disease resolution.

Trichomoniasis symptoms in men range from none to urethritis complicated by prostatitis. Nongonococcal nonchlamydial urethritis is the most common symptom reported by men with trichomoniasis. Symptoms of urethritis include the following: [57]

  • Discharge (purulent to mucoid in character)
  • Dysuria
  • Urethral pruritus

Less-common symptoms may include the following:

  • Pain in the urethra
  • Testicular pain
  • Lower abdominal pain

Most symptomatic T vaginalis infections in men are intermittent and self-limiting.


Physical Examination


Vaginal discharge is found in 42% of women with trichomoniasis. [16] The discharge is classically described as thin and frothy; however, this is only seen in about 12% of patients. [16] The discharge is often yellow and is sometimes viscous enough to be confused with candidiasis. Abnormal vaginal odor was found in approximately half of infected women, and edema or erythema was found in 22%-37%. [16] Vaginal pH is often elevated (>4.5). [61]

One of the classic signs of ​T vaginalis infection is colpitis macularis, or strawberry cervix, which describes a diffuse or patchy macular erythematous lesion of the cervix. This is a specific sign of trichomoniasis but is visible in only 1%-2% of cases without the aid of colposcopy; with colposcopy, colpitis macularis is detected in up to 45% of cases. [52] Together, colpitis macularis and frothy vaginal discharge have a specificity of 99%; individually, they have positive predictive values of 90% and 62%, respectively.

Lower-abdominal tenderness may be present, although this is described in fewer than 10% of patients. If this occurs, coexisting salpingitis or an intra-abdominal pathology is possible.

Coexisting Neisseria gonorrhoeae infection, candidiasis, and bacterial vaginosis are common and may produce a mixed clinical picture.

Most of the symptoms described above are not specific for trichomoniasis and can occur in other vaginal or cervical infections. In one study, the clinician’s ability to accurately diagnose T vaginalis infection on the basis of physical findings alone had a positive predictive value of only 47%. [62] Relying on physical examination findings alone misses the diagnosis of most patients with trichomoniasis. Definitive diagnosis requires appropriate laboratory testing.


Most men with trichomoniasis have no physical findings. Infrequently, infected men have abnormal penile discharge. However, the discharge usually is only scant and thin. Trichomoniasis in men may be associated with local inflammatory states, including balanitis and balanoposthitis. Epididymitis and prostatitis may also be present. [63]


In female newborns, T vaginalis acquired during birth may cause vaginal discharge during the first week of life. Respiratory infection in newborns is also possible. [48] An infected infant may present with fever.

Prepubertal children with trichomoniasis may present with symptoms similar to those seen in the adolescent and adult patient. T vaginalis infection in prepubertal children may suggest sexual abuse but may also arise from earlier vertical transmission.



In women, vaginitis is the most common manifestation of infection. Other complications include cervicitis and infection of the adnexa, endometrium, and Skene and Bartholin glands. Pelvic inflammatory disease and tubo-ovarian abscess may also occur.

In symptomatic men, T vaginalis infection usually manifests as urethritis. As many as 11% of nongonococcal urethritis cases in men are caused by T vaginalis. [64] Complications of untreated trichomoniasis in men include prostatitis, epididymitis, urethral stricture disease, and infertility, potentially resulting from decreased sperm motility and viability. [6, 65]

Research has shown T vaginalis infection increases the risk of HIV transmission in both men and women. [3, 1] It is estimated that, in women alone, 747 new HIV cases per year result from the facilitative effects of T vaginalis on the transmission of HIV. [66] Overall, persons with trichomoniasis are twice as likely to develop HIV infection as the general population. [35] Symptomatic men with comorbid T vaginalis and HIV infections have been found to have significantly higher numbers of HIV RNA particles in their seminal fluid. [3] Treatment of trichomoniasis has been shown to decrease the rate of viral shedding in patients with HIV infection. [3, 67]

In addition to HIV, T vaginalis infection also increases the susceptibility to other viruses, including herpes and human papillomavirus (HPV). T vaginalis may increase the rate of infection or reactivation of HPV, although it may also shorten the duration of infection. [68]

The following disorders have also been associated with trichomoniasis:

  • Cervical intraepithelial neoplasia [69]
  • Posthysterectomy infection, including cuff cellulitis, cuff abscess, and wound infection [70]
  • Trichomonal peritonitis (rare) [71]

In pregnant women, T vaginalis infection has been associated with an increased risk of low birth weight, preterm delivery, and intrauterine infection. [72, 1] Neonatal trichomoniasis, usually presenting as a genital infection, has been described. [19] Rarely, trichomoniasis presents as a serious respiratory infection. [11]