In shortThe basic STI PCR panel covers chlamydia, Mycoplasma genitalium, gonococcus and trichomonads — all from one swab. Test no earlier than 2–3 weeks after contact. Mycoplasma hominis and ureaplasma are opportunistic: their finding without inflammation usually needs no treatment.
About the infection
STIs are a group of sexually transmitted infections. The main bacterial pathogens (chlamydia, gonococcus, Mycoplasma genitalium, trichomonads) are detected by PCR — by pathogen DNA/RNA fragments in a swab. It is the most sensitive method.
It is important to separate obligate pathogens (chlamydia, gonococcus, trichomonads, Mycoplasma genitalium — always meaningful) from opportunistic flora (ureaplasma, Mycoplasma hominis), present in many healthy people and judged only together with inflammation.
Diagnostic methods
| Method | What it shows | When it is used |
|---|---|---|
| STI PCR panel | DNA/RNA of chlamydia, gonococcus, M. genitalium, trichomonads | Basic workup for complaints and after a risky contact |
| Flora swab (microscopy) | Inflammation (leukocytes) and flora composition | Discharge, itching, discomfort; a pair to PCR |
| Culture with sensitivity | The pathogen and its antibiotic resistance | With treatment failure and gonorrhea |
| Blood: HIV, syphilis, hepatitis B/C | Systemic infections of the same risk group | Complement swabs in a full workup |
Window period: when the test becomes reliable
PCR for bacterial STIs is reliable 2–3 weeks after contact. HIV and syphilis have longer windows — 6 weeks and 3 months for conclusive answers, so a full post-contact workup is planned by the longest window.
How to prepare
A swab from the urethra (men) or cervical canal/vagina (women). Men — no urination 1.5–2 hours before. For 1–2 days avoid local products; not taken during menstruation. After antibiotics — no earlier than 3–4 weeks.
Reading the result
| Result | What it means |
|---|---|
| No pathogens detected | No bacterial STIs from the panel (if > 2–3 weeks since contact) |
| Chlamydia / gonococcus / trichomonads / M. genitalium “+” | A meaningful finding — doctor’s treatment, partner testing |
| Ureaplasma / M. hominis “+” without inflammation | Carriage: treatment usually not needed — the doctor judges |
| Any “+” with symptoms | Do not postpone the visit: untreated STIs cause complications, including infertility |
When a retest makes sense
Cure control by PCR — no earlier than 3–4 weeks after antibiotics end: earlier the test catches DNA remnants of dead pathogens. Partner testing and treatment go simultaneously.
Which specialist to see
A positive or doubtful result is reviewed by: Gynecologist, urologist, dermatologist-venereologist. Note the date of the first test and the possible contact — the retesting plan depends on it.
Several markers on your report?
The app reads your whole report — this marker together with its neighbors, not one by one.
Frequently asked questions
When after an unprotected contact should I take an STI panel?
The PCR panel — at 2–3 weeks. Blood for HIV and syphilis has a longer window: conclusive answers at 12 weeks. A doctor will map the test timeline.
Ureaplasma positive — treat it?
A ureaplasma finding alone, without inflammation and complaints, usually needs no treatment: it is opportunistic flora present in many healthy people. The doctor decides from the flora swab picture and complaints.
Can testing be anonymous?
Yes: STI testing is available anonymously in specialized clinics and private laboratories.
Sources
- MedlinePlus — Hepatitis Panel — MedlinePlus (medlineplus.gov). Accessed: September 17, 2026.
- MSD Manuals — Helminths — MSD Manuals (msdmanuals.com). Accessed: September 17, 2026.