Chlamydia in Black Women: The Screening Test to Ask For

Chlamydia is the most commonly reported bacterial infection in the United States. In 2023 the CDC recorded a case rate of 6,736.8 per 100,000 among Black women aged 20 to 24, about one reported infection for every 15 women in that age band in a single year. It is silent in most women who carry it, so you do not catch it by noticing a symptom. You catch it by asking for a test.

In September 2021 the US Preventive Services Task Force reaffirmed a grade B recommendation to screen for chlamydia and gonorrhea in all sexually active women 24 and younger, and in women 25 and older at increased risk. Grade B is the category most private plans must cover without cost sharing. For women over 24, increased risk means a new partner, more than one partner, a partner who has other partners, or a partner with an STI.

Now the part that matters more. A study of 68,935 well visits across a 31 clinic pediatric primary care network found a mean annual screening rate of 11.1 percent among female patients aged 15 to 19, a group the recommendation covers without qualification. Health plan data agrees: from 2011 through 2020, screening among sexually active women aged 16 to 24 ran between 46.9 and 52.4 percent in commercial plans and 55.0 to 61.8 percent in Medicaid plans, with no significant improvement.

This is a gap you can close yourself, because the test has a name. Ask for chlamydia and gonorrhea NAAT testing. For women it runs on a vaginal swab or first catch urine, and a swab you collect yourself performs as well as one a clinician collects. If you have receptive anal sex, say so and ask whether a rectal swab should be added, because urine and vaginal samples do not test the rectum. Our guide to what a standard panel covers and skips lists everything worth naming out loud.

A study that screened 1,631 people aged 18 to 29 and reconstructed their symptom histories estimated that 77 percent of chlamydia infections were never symptomatic, and that 95 percent of untreated cases went untreated for that reason alone. Not because people ignored symptoms. Because there were none.

When symptoms do appear they are unremarkable: abnormal discharge, bleeding between periods or after sex, burning with urination, pelvic pain, pain during sex. Every one overlaps with something more familiar, which is why chlamydia gets treated as a yeast infection, a urinary tract infection, or bacterial vaginosis and never tested for. Discharge or burning that an over the counter antifungal does not fix is a reason to ask for an STI test, as our guide to yeast infections in Black women lays out.

Untreated chlamydia can ascend from the cervix into the uterus and fallopian tubes and cause pelvic inflammatory disease. PID is the event that does the lasting damage. Be careful with the progression figures you will see quoted. An expert review convened by the CDC found no prospective study directly measuring long term reproductive damage after untreated chlamydia, found published PID rates varying too widely to support a single estimate, and concluded that progression in the general asymptomatic population appears low.

A randomized trial of 2,529 female students in London gives the clearest single figure. Among women who tested positive at baseline and were not treated, 9.5 percent developed clinical PID within 12 months, against 1.6 percent of those screened and treated. The same trial found 79 percent of all PID episodes occurred in women who tested negative at baseline. Screening prevents the PID that chlamydia causes, not all PID.

What PID costs is measurable. In a cohort of 1,844 women with PID confirmed by laparoscopy, 10.8 percent had confirmed tubal factor infertility afterward, against none of the controls with normal laparoscopies. The ectopic rate for a first pregnancy after PID was 9.1 percent, against 1.4 percent in controls, and damage rose with the number of episodes. Our guide to infertility care and IVF access for Black women covers what evaluation looks like.

In 2023 the CDC reported a chlamydia case rate of 1,342.2 per 100,000 among Black women across all ages, and 6,736.8 per 100,000 among Black women aged 20 to 24, roughly one reported case for every 15 women in that age group in one year. This is a common infection in a specific age band.

Say the limitation in the same breath as the number. Surveillance counts infections that were diagnosed and reported, not infections that exist. The CDC's own technical notes state that because chlamydia is usually asymptomatic, the number of infections identified and reported rises as more people are screened, even when incidence is flat or falling. Screening is not applied evenly: in the network study above, individual clinicians were more likely to order a chlamydia test for their Black patients than their non-Black patients, which the authors attributed to racial bias. More testing finds more infection, and nobody can say how much of the reported gap that accounts for.

The remaining difference is real, and the evidence on why points away from behavior. The CDC states these disparities are unlikely to be fully explained by differences in sexual behavior, and points to differential access to sexual health care and to sexual network characteristics. The 2021 National Academies review found no data indicating any biological reason. A 1999 network analysis described the mechanism: when background prevalence inside a partially segregated sexual network is higher, the risk carried by each encounter is higher, no matter how many partners any individual has. Black Americans do not report more partners on average.

The CDC's 2021 STI Treatment Guidelines moved the recommended regimen for chlamydia in adolescents and adults to doxycycline 100 mg orally twice a day for 7 days. Azithromycin 1 gram as a single dose and levofloxacin 500 mg daily for 7 days are now alternatives. If you were treated years ago with one dose of azithromycin and assumed that is still standard, it is not.

The reason matters for women specifically. Doxycycline outperforms azithromycin against rectal chlamydia, which is more common in women than most people expect. A published review found C. trachomatis at the rectal site in 33 to 83 percent of women who had urogenital chlamydia, and its presence was not predicted by whether the woman reported receptive anal sex. Inadequately treated rectal infection can reseed the genital tract.

Three rules come attached. Abstain from sex for 7 days after finishing the course and until every partner is treated. Male partners are rarely screened for chlamydia at all, so what a man has to ask for is worth knowing. Get tested for HIV, gonorrhea, and syphilis at the same visit. Skip the test of cure if you are not pregnant: a NAAT run under 4 weeks after therapy can detect dead organisms and return a false positive. In pregnancy, doxycycline is contraindicated in the second and third trimesters, the recommended regimen is azithromycin 1 gram, and a test of cure about 4 weeks later is recommended.

Everyone treated for chlamydia should be retested roughly 3 months after treatment, whether or not you believe your partners were treated. Book it the day you are treated. The CDC is explicit that most post treatment infections are reinfections, not treatment failures. Repeat infection raises PID risk, and PID damage accumulates with each episode.

The other half is partner treatment. Anyone you had sex with in the 60 days before your symptoms or diagnosis should be tested and treated, plus your most recent partner even if that was longer ago. When a partner cannot be seen promptly, expedited partner therapy is the workaround: your clinician sends medication or a prescription home with you for your partner without examining them. The CDC calls it a useful option, especially for male partners of women with chlamydia, because it lowers recurrent chlamydia in women. Legality varies by state, so ask your clinician directly.

Bring one sentence to your next routine visit: "I would like chlamydia and gonorrhea NAAT testing today." You do not need symptoms to justify it, though sharing a sexual history helps your clinician decide whether to add a rectal or throat swab. If you test positive, ask for the doxycycline course, ask whether your state allows expedited partner therapy, and put the 3 month retest on the calendar before you leave. You can find a Black OB-GYN or primary care clinician in our directory.