Pelvic inflammatory disease (PID): symptoms, causes and consequences

Pelvic inflammatory disease is an infection that has travelled up from the vagina into the uterus, the fallopian tubes or the ovaries. In most cases a chlamydia or gonorrhoea that was not found in time sits behind it. That is the single most useful thing to know about it, because both are detectable with an ordinary test long before they get that far.

The abbreviation you meet everywhere is PID.

Here is what strikes me about this topic: almost every page written about it addresses someone who already has the diagnosis. That makes sense, because those pages come from hospitals. But the question people actually send us comes earlier. They have a nagging pain low in the abdomen, they had unprotected sex a few weeks ago, and they want to know whether those two things are connected.

That is what this article is about.

What exactly is pelvic inflammatory disease?

It is inflammation of the female reproductive organs above the cervix. Bacteria that normally stay in the vagina move upward and cause inflammation in the uterus, the fallopian tubes or the surrounding tissue. Doctors use PID as an umbrella term, because more than one organ is often involved at the same time.

The cervix normally works as a threshold. Its mucus and narrow opening hold back most of what lives in the vagina.

Chlamydia and gonorrhoea are good at getting past that threshold. Research into the mechanisms describes how both bacteria evade the local immune response, which lets them establish themselves in the upper genital tract (Darville, 2021). When that succeeds, you get the inflammation we call PID.

You will also meet the individual names. Inflammation of the fallopian tubes alone is salpingitis, inflammation of the uterine lining is endometritis. In practice these pictures overlap, which is exactly why an umbrella term exists.

How do you recognise pelvic inflammatory disease?

Usually by pain low in the abdomen that does not pass, often on both sides. Alongside it can come discharge that smells or looks different from what you are used to, bleeding between periods, pain during sex, and fever. Not everyone gets every symptom, and some women barely notice anything.

That last part is what makes it difficult.

No single symptom proves it. A review of the diagnostics calls this the core problem in as many words: there is no simple test that confirms or rules out PID. Doctors have to weigh the whole picture instead (Hillier, 2021).

An ultrasound can also look normal while inflammation is present.

What you can do yourself is watch for change. Pain that is new, feels different from your usual period pain, and lasts more than a few days is the kind of change a GP can work with.

And then the level-headed side of this story, because it belongs here too.

Lower abdominal pain is a common complaint with many possible causes. In the Netherlands endometriosis is searched for roughly eighty times more often each month than pelvic inflammatory disease, and general abdominal pain more often still. Abdominal pain rarely points straight at an STI. That is allowed to be reassuring.

How do you get pelvic inflammatory disease?

Usually through an STI that was not found in time. Chlamydia and gonorrhoea together account for most cases. Bacteria that live in the vagina naturally can also play a part, particularly at moments when the cervix is open.

Those moments are concrete: during a period, after childbirth, after a miscarriage or termination, and around the fitting of an IUD.

One study is particularly useful on how often this goes wrong. The British POPI trial followed more than two thousand young women for a year. Women who turned out to have had a chlamydia infection developed PID more often over that year than women who had not (Oakeshott, 2010).

The pattern behind that is not complicated. The longer an infection goes unnoticed, the more time it has to travel upward.

The Dutch national institute RIVM reports the same thing year after year. Chlamydia is the most frequently found STI here, and the numbers are highest among people under twenty-five. That is the same age group in which PID is seen most often. How chlamydia itself behaves is covered in chlamydia: symptoms, testing and consequences, and the second culprit in recognising and testing for gonorrhoea.

When is it urgent and when can you test first?

Severe abdominal pain with fever, nausea or feeling genuinely unwell needs same-day assessment by a doctor. Mild symptoms that persist without fever make a targeted STI test a sensible first step. The difference sits in how ill you are, not in how certain you are about the cause.

This table exists to make that choice easier.

A table does not make a diagnosis. What it does is stop you waiting on a test result when what you actually need is a doctor.

Is pelvic inflammatory disease dangerous?

Treated, usually not. Untreated, it can leave scar tissue in the fallopian tubes, and that scar tissue is where the long-term consequences come from. Think reduced fertility, a higher chance of an ectopic pregnancy, and sometimes lasting pain low in the abdomen.

Here are the numbers, and they come from the study most pages point at without naming it.

A Swedish cohort followed 1,844 women with laparoscopically confirmed PID over many years, alongside 657 women whose laparoscopy showed nothing. Among those trying to conceive, 16.0 percent of the patients did not manage it, against 2.7 percent of the controls. Tubal damage as the cause occurred in 10.8 percent of patients and in none of the controls (Weström, 1992).

The ectopic pregnancy risk differed clearly too. Of first pregnancies after the laparoscopy, 9.1 percent were ectopic among patients, against 1.4 percent among controls.

Read those figures carefully. They describe women in whom inflammation was actually confirmed, so this is not a risk everyone with abdominal pain carries.

What they do show is why there is urgency in finding the underlying infection. Most women treated in time are left with nothing. What causes damage is the stretch of time in which nobody knew anything was going on. We took that reasoning further in chlamydia complications and infertility.

What if you have no symptoms at all?

An infection can still be there. Chlamydia runs without noticeable symptoms in a large share of people, and that holds for a share of pelvic infections too. The Swedish cohort included women whose inflammation was only found once damage had already occurred.

This is the strongest argument I know for testing after a risk moment.

Not because something is wrong, but because a test is the only way to find a silent infection. How symptom-free STIs behave is covered in STIs without symptoms.

You can get checked with us through a test for chlamydia, gonorrhoea and trichomonas, without an appointment and without anything reaching your GP records. Which waiting time fits which infection is covered in which test you need when.

What do you do about pelvic inflammatory disease?

Treatment means antibiotics prescribed by a doctor, usually a combination, because more than one bacterium is often involved. With severe symptoms that sometimes happens in hospital through a drip. The Dutch GP standard on the STI consultation describes how GPs here approach this picture.

What you do not do is wait for it to pass, or reach for an old course of antibiotics in the cupboard.

Two things get forgotten a lot. Treating your partner as well is part of it, otherwise you are reinfected the moment you have sex again. And finishing the course counts even if the pain is gone after three days.

Picture this: you are 23, you have had a nagging pain on the lower left for a week and a half, and you had a new partner a month ago. No fever, not otherwise unwell. There is no reason to panic, and equally no reason to carry it around for another three weeks.

Thuisarts.nl explains in plain language what to expect from a GP visit for lower abdominal pain. What happens after a positive result is covered in tested positive, what now.

Does pelvic inflammatory disease exist in men?

Not under that name, because men have no fallopian tubes or uterus. The underlying story is the same though. The same bacteria can travel upward in men from the urethra, and then they end up in the epididymis or the prostate.

That connection is almost never drawn, and it is a shame.

In epididymitis under thirty-five, chlamydia and gonorrhoea are often the cause, the same two that sit behind PID in women of that age (Street, 2017). It is the same infection in different anatomy. For couples getting checked together that is a more useful picture than two separate conditions that happen to appear at once.

In men the start of that upward move is often urethritis. If it goes further, read about the epididymis in recognising epididymitis and about the prostate in prostatitis and the STI link.

Further reading

For the individual components of PID: salpingitis and endometritis.

For what can happen to your fertility afterwards: blocked fallopian tubes and STIs and trying to conceive.

For the wider symptom picture in women: STI symptoms in women and discharge and when it points to an STI.

References

• Weström L, et al. Pelvic inflammatory disease and fertility. A cohort study of 1,844 women with laparoscopically verified disease and 657 control women with normal laparoscopic results. Sexually Transmitted Diseases, 1992;19(4):185-92. PMID 1411832.
• Oakeshott P, et al. Randomised controlled trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial. BMJ, 2010. PMID 20378636.
• Hillier SL, et al. A Review of the Challenges and Complexities in the Diagnosis, Etiology, Epidemiology, and Pathogenesis of Pelvic Inflammatory Disease. The Journal of Infectious Diseases, 2021. PMID 34396398.
• Darville T. Pelvic Inflammatory Disease Due to Neisseria gonorrhoeae and Chlamydia trachomatis: Immune Evasion Mechanisms and Pathogenic Disease Pathways. The Journal of Infectious Diseases, 2021. PMID 34396413.
• Street EJ, et al. The 2016 European guideline on the management of epididymo-orchitis. International Journal of STD and AIDS, 2017;28(8):744-749. PMID 28632112.
• RIVM, Sexually transmitted infections in the Netherlands, annual report. Accessed July 2026.
• NHG-Standaard Het soa-consult, Dutch College of General Practitioners. Accessed July 2026.
• Thuisarts.nl, I have pain in my lower abdomen. Accessed July 2026.

Every test result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.