Pelvic Inflammatory Disease (PID): Symptoms, Causes and Treatment

What is pelvic inflammatory disease?

Pelvic inflammatory disease, or PID, is an infection of one or more of the female reproductive organs: the uterus, the fallopian tubes, the ovaries or the surrounding pelvic area.¹

It happens when an infection spreads upwards from the cervix.¹

Pelvic inflammatory disease symptoms

Symptoms can include:¹

• Pain in the lower abdomen or pelvis
• Deep pain during sex
• Unusual vaginal discharge, which may contain blood or pus
• Bleeding between periods or after sex
• Heavy periods
• Fever, chills, nausea or vomiting

Some people have no symptoms at all, which makes PID hard to spot.¹

What causes it?

PID is often caused by a sexually transmitted infection (STI) such as chlamydia or gonorrhoea. It can also be caused by bacteria that normally live in the vagina.¹

Chlamydia matters most because it so often causes no symptoms. Modelling of studies that followed women with untreated chlamydia estimated that about 16 per cent of infections lead to PID.²

You have a higher chance of PID if you have:¹

• A new sexual partner
• More than one sexual partner
• A partner with an STI, or with symptoms of one

IUDs and procedures

More rarely, PID can follow a surgical abortion or the insertion of an intrauterine contraceptive device (IUD).¹ The risk with an IUD is small and short-lived. In an international analysis of 22,908 insertions, the overall rate of PID was 1.6 cases for every 1,000 years of use. The risk was more than six times higher in the first 20 days after insertion than later, and stayed low for up to eight years after that.³

Why early treatment matters

Untreated PID can scar the fallopian tubes. That can lead to:¹

• Fertility problems
• Ectopic pregnancy, where a pregnancy develops outside the uterus
• Long-term pelvic pain

Speed matters. In one study, women who delayed seeking care for PID were three times more likely to have infertility or an ectopic pregnancy than those who were treated promptly.⁴

Repeat infections add to the damage. In a long-term follow-up of women treated for PID, those who had it again were almost twice as likely to have infertility and more than four times as likely to develop chronic pelvic pain.⁵

How is it diagnosed?

A doctor diagnoses PID from your symptoms and an examination. The examination usually includes an internal check for tenderness, and swabs from the vagina and cervix to look for the infection responsible. Sometimes no bacteria are found.¹

You can ask for a support person to be with you, and if you would prefer not to be examined, you may be able to take the swab yourself.¹

Other tests check for different causes of the pain:¹

• A pregnancy test
• Blood and urine tests
• An ultrasound

Treatment

PID is treated with a combination of antibiotics, usually for 2 weeks. Treatment can start straight away, without waiting for the swab results.¹

• Finish the course, even if you feel better within a few days.
• Rest while you recover. Simple pain relief and anti-inflammatory medicines can help with the pain.¹
• Avoid sex for at least one week after treatment.¹
• Partners need treating too. Your current partner should be tested and treated, and previous partners may need to be checked.¹

Most people are treated at home. In a trial of women with mild to moderate PID, those treated as outpatients did just as well as those treated in hospital, including on later pregnancy rates.⁶

Hospital treatment, with antibiotics through a drip, may be recommended if you have severe symptoms such as fever or vomiting, or if you are pregnant.¹

Can PID be prevented?

• Use condoms. They help protect against STIs.¹
• Get tested for STIs. In a trial of 2,607 women at higher risk, those offered chlamydia screening had fewer than half as many cases of PID during follow-up as those given usual care.⁷ A later trial found a smaller benefit, and noted that most cases of PID occurred in women who had tested negative, a reminder that a single test is not lasting protection.⁸
• Tell partners. The free Let Them Know service lets you notify partners that they may be at risk.¹

PID or something else?

Pelvic pain has many causes, and several of them overlap with PID. If the pain is long-standing or follows your cycle, our guides to endometriosis symptoms, adenomyosis, ovarian cysts and pelvic congestion syndrome may help.

When to see a doctor

See a doctor if you have symptoms of PID. It is especially important if you are sexually active and have a new type of pain in your pelvis.¹

Go to an emergency department if you have:

• Severe pain in your lower abdomen
• Pelvic pain with a high fever or vomiting
• Pelvic pain and you are, or could be, pregnant. An ectopic pregnancy is an emergency

References

1. healthdirect. Pelvic inflammatory disease.
2. Price MJ, Ades AE, De Angelis D, et al. Risk of pelvic inflammatory disease following Chlamydia trachomatis infection: analysis of prospective studies with a multistate model. Am J Epidemiol. 2013;178(3):484-92.
3. Farley TM, Rosenberg MJ, Rowe PJ, et al. Intrauterine devices and pelvic inflammatory disease: an international perspective. Lancet. 1992;339(8796):785-8.
4. Hillis SD, Joesoef R, Marchbanks PA, et al. Delayed care of pelvic inflammatory disease as a risk factor for impaired fertility. Am J Obstet Gynecol. 1993;168(5):1503-9.
5. Trent M, Bass D, Ness RB, et al. Recurrent PID, subsequent STI, and reproductive health outcomes: findings from the PID evaluation and clinical health (PEACH) study. Sex Transm Dis. 2011;38(9):879-81.
6. Ness RB, Soper DE, Holley RL, et al. Effectiveness of inpatient and outpatient treatment strategies for women with pelvic inflammatory disease: results from the Pelvic Inflammatory Disease Evaluation and Clinical Health (PEACH) Randomized Trial. Am J Obstet Gynecol. 2002;186(5):929-37.
7. Scholes D, Stergachis A, Heidrich FE, et al. Prevention of pelvic inflammatory disease by screening for cervical chlamydial infection. N Engl J Med. 1996;334(21):1362-6.
8. Oakeshott P, Kerry S, Aghaizu A, et al. Randomised controlled trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial. BMJ. 2010;340:c1642.