Woman experiencing uncomfortable symptoms and wondering what causes pelvic inflammatory disease

What Causes Pelvic Inflammatory Disease?

Written on June 25, 2023 by Amy Harris, MS, RN, CNM. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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Many hesitate to seek medical advice about confusing symptoms, especially when talking about sexual health. Regardless of your reasons for avoiding a sexual health check-up, pelvic inflammatory disease (PID) is one infection you don’t want to ignore. PID is one of the most common causes of chronic pelvic pain, infertility, and tubal pregnancies — yet you can prevent all of these scary-sounding complications by avoiding getting PID in the first place.[1]

What is Pelvic Inflammatory Disease?

Pelvic inflammatory disease is an infection that occurs in your uterus (womb), fallopian tubes, or ovaries — the female reproductive organs. PID affects approximately 1 million women and people assigned female at birth (AFAB) annually in the US.[1] People between 15 and 25 most commonly get PID.[2] Women having sex with women or those AFAB can still get PID because the bacteria that cause PID can be found in vaginas, penises, or any object placed in your vagina.[3]

What Causes Pelvic Inflammatory Disease?

Bacteria, usually from sexually transmitted infections (STIs), cause PID infections.[2] Chlamydia and gonorrhea are the most frequent cause of PID.[1] PID happens when bacteria from the vagina spread up through your cervix into your uterus, into the tubes that run between your uterus and ovaries (called fallopian tubes), and around your ovaries. It can take several days to weeks from being infected with chlamydia and gonorrhea until you develop PID.[1]

In general, PID caused by gonorrhea is more severe than chlamydial PID.[2] PID caused by chlamydia is less likely to cause noticeable symptoms, leading to what providers call subclinical PID.[2] The problem with subclinical PID is that even though you may not have any symptoms, it can still have long-term effects on your reproductive system.

Gonorrhea and chlamydia infections do not always cause PID, however. Just because you have either of these common STIs does not mean you will automatically get PID.[4]

Are All PID Cases the Result of Sexually Transmitted Infections?

No. Other bacteria and smaller microorganisms living in your vagina can also cause PID. If these organisms are accidentally transmitted up through your cervix, they can cause a pelvic infection.[5] These types of PID infections can occur after a miscarriage, childbirth, or surgical procedure and after the insertion of an intrauterine device (like a Mirena or Paragard).[4]

What Are the Symptoms of PID?

Not everyone notices right away that they have PID. You might only have mild or no symptoms.[1] People with PID usually have some of the following symptoms [1-5]:

  • Lower belly or pelvic pain ranging from mild to severe
  • Pain or cramping with intercourse
  • Irregular or unusual bleeding, especially after sex or in between your periods
  • Unusual or heavy vaginal discharge that can have an unpleasant odor
  • Fever and chills
  • Having to pee more often or feeling pain when urinating

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Is There a Test for PID?

No. PID is diagnosed based on your symptoms, risk factors, and whether you test positive for any other vaginal infections such as gonorrhea, chlamydia, or bacterial vaginosis.[5] PID diagnosis requires a healthcare provider to examine you in person.[2] During this appointment, you should have a pelvic exam to check your reproductive organs and feel for tenderness or abscesses (collections of pus).[5] You may also have the other following tests [3]:

  • Vaginal cultures
  • Urine test for a urinary tract infection (UTI)
  • Blood test
  • Ultrasound

How is PID Treated?

Fortunately, when caught early, PID can be fully treated and cured.[6] Medications called antibiotics treat the bacteria responsible for causing PID. These antibiotics can be taken as pills, as a shot, or through an IV if you are so sick with PID that you need to be hospitalized.[5] Unfortunately, even with PID treatment, you can’t undo any damage the infection may have already caused.[6]

Why Treatment for PID is So Important

If not treated right away, PID can lead to life-changing health conditions such as [2,5]:

  • Infertility
  • Chronic pelvic pain
  • Ectopic pregnancy
  • A greater likelihood that you will get PID more than once

Untreated PID causes scarring of the tubes that carry eggs to your uterus. They become blocked and don’t work. Sperm can not get to an egg, and fertilization does not occur. About one out of every ten people with PID will become infertile, an estimated 100,000 people each year.[1]

If the scarring does not block the egg from being fertilized, it can make its trip down through the fallopian tubes into your uterus more treacherous. Sometimes a fertilized egg can get stuck in a scarred tube, causing an ectopic or tubal pregnancy. Ectopic pregnancies can be life-threatening emergencies if the fertilized egg begins to grow in the tube.[1]

PID-related scar tissue can also cause parts of your reproductive tract to stick together. These adhesions are like chewing gum that can velcro together your pelvic organs and even parts of your digestive tract. Such adhesions can cause painful sex, painful bowel movements, and chronic pelvic pain. One out of every three people with PID will develop chronic pelvic pain.[2]

How Can You Reduce Your Risk of PID?

  1. Always have protected sex.
  2. Get tested regularly for STIs even if you don’t have any symptoms.
  3. Limit the number of sexual partners you have.
  4. See a healthcare provider immediately if you notice changes in vaginal symptoms or periods or start having pain with sex.
  5. Complete all STI treatments as prescribed if you do have an STI. Do not have sex with any partners until all of you complete treatment (usually at least a week).
  6. If diagnosed with PID, return for a follow-up appointment and retest for STIs at least three months after your original diagnosis.[5]
  7. Do not douche. Douching can impact your healthy vaginal microbiome, sometimes making it easier for you to get other vaginal infections, and can transmit harmful bacteria up through your cervix.[4]

Everlywell Can Be a Part of Your PID-Prevention Plan

Stay on top of your sexual health by familiarizing yourself with the most common STI symptoms and how to test for STIs.

Everlywell offers you convenient at-home STI testing so you can test yourself regularly or when the symptoms of STIs start. You can schedule a private telehealth STD consult to sort through your possible STI symptoms and determine whether you should see an in-person provider to diagnose PID.

Remember, quick diagnosis and treatment of STIs will reduce your chances for PID. With PID, prevention is the best way to avoid long-term health conditions like pelvic pain, infertility, ectopic pregnancy, and pelvic pain. Everlywell is here to ensure you can access the sexual healthcare that should be a part of everyone’s PID-prevention plan.

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  1. Pelvic Inflammatory Disease. American College of Obstetricians and Gynecologists. Reviewed June 2022. Accessed June 16, 2023. URL.
  2. Jennings L and Krywko D. Pelvic inflammatory disease. Statpearls. National Institutes of Health. March 13, 2023. Accessed June 15, 2023. URL.
  3. Pelvic Inflammatory Disease. Cleveland Clinic. Published February 8, 2023. Accessed June 15, 2023. URL.
  4. Pelvic inflammatory disease. Mayo Clinic. Published April 30, 2022. Accessed June 15, 2023. URL.
  5. Pelvic Inflammatory Disease (PID). Sexually Transmitted Infections Treatment Guidelines 2021. Centers for Disease Control and Prevention. Published September 21, 2022. Accessed June 16, 2023. URL.
  6. Pelvic Inflammatory Disease (PID), CDC Basic Fact Sheet. Centers for Disease Control and Prevention. Reviewed April 18, 2022. Accessed June 16, 2023. URL.
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