Pelvic Inflammatory Disease (PID)
PID is an infection of the female reproductive organs, notably the fallopian tubes, ovaries and the womb. It can sometimes affect the lining of the pelvis in more severe cases.
Whilst it is commonly diagnosed in women between the ages of 15 and 24, PID affects women of all ages during their reproductive years.
PID is often caused by underlying sexually transmitted infections, such as Chlamydia, Gonorrhoea, and Mycoplasma genitalium. However, in upto half of the patients it can be due to underlying Bacterial vaginosis (BV) which is a major risk factor for PID.
Approx. 25% of PID is the result of an STI
Approx. 10% of women with untreated Chlamydia may develop PID
Approx. 10% of women with PID may become infertile
Symptoms of PID
What are the symptoms of PID?
In early stages of PID (or low grade PID), one may not experience typical symptoms of PID. However, your clinician should be able to rule out the diagnosis after a thorough assessment and clinical examination of your pelvis.
Typical symptoms of PID may include:
- Pain in the lower abdomen (can be present in one or both sides)
- Pelvic discomfort pain
- Pain during sex (Dyspareunia)
- Bleeding after sex (Post-coital bleeding)
- Bleeding between periods (Inter-menstrual bleeding)
- Abnormal vaginal discharge
- Heavy periods
- Lower back pain
- Painful urination (Dysuria)
In acute cases of PID, one may experience the following symptoms:
- Severe abdominal (or pelvic) pain
What are the complications of PID?
Tubo-ovarian abscess (short term complication)
Infections in the fallopian tube can lead to the formation of a local abscess which can also affect the adjacent ovary. Such tubo-ovarian abscess is the most serious complication of PID in the short term and sometimes may need a hospital admission and a surgical intervention.
Tubo-ovarian abscess can cause serious damage to the genital tract resulting in increased risk of infertility and risk of ectopic pregnancy.
Fitz-Hugh Curtis syndrome (short term complication)
Rarely, the patients may experience pain in the upper abdomen on the right side, far away from the site of genital infection. This happens due to the occurrence of inflammation around the liver (perihepatitis) as a consequence of an upward spread of the infection in PID (especially seen in those with Chlamydia trachomatis infection).
Infertility (long term complication)
PID reduces fertility by producing local damage to the fallopian tubes and to a lesser extent the uterine lining. The extent of the reduction in fertility commonly depends on the following four factors:
- The severity of PID
- The longer the condition remains undiagnosed and untreated, the greater the risk of becoming infertile.
- Those who have recurrent PID are at a greater risk of infertility.
- As one gets older, every woman has a reduction in fertility that can be further compounded by the history of episodes of PID.
Ectopic pregnancy (long term complication)
PID can cause scarring and consequent narrowing of the fallopian tubes. As a result, the egg becomes stuck in the fallopian tube on its journey to the uterus and if there is a risk of pregnancy, then implantation happens in the fallopian tube itself. This is called an ectopic pregnancy – a medical emergency and requires immediate treatment to avoid serious health consequences.
This is also one of the reasons why we will conduct a pregnancy test, if there is any risk of pregnancy.
Chronic pelvic & back pain (long term complication)
In some women, chronic inflammatory changes in the pelvis can produce a dull ache in the lower abdomen, pelvis, as well as the lower back after the original infection has been adequately treated.
This is why it is important to take the diagnosis of PID seriously and manage it adequately.
Pelvic adhesions (long term complication)
Acute inflammation in PID can give rise to formation of scar tissue in the pelvis during the healing process with loss of natural mobility of pelvic organs. Such adhesions can also result from previous surgical procedures and endometriosis. Sometimes laparoscopic breakage of such adhesions are undertaken to relieve pelvic pain, but prevention is always much better than cure.
Causes of PID
What causes Pelvic Inflammatory Disease?
PID is a consequence of bacterial infection in the pelvis. We routinely break them down into three categories:
(a) STI causes of PID:
- Mycoplasma genitalium
- Trichomonas vaginalis (as a consequence of the bacterial vaginosis it can produce)
(b) Non-STI causes of PID:
- Bacterial vaginosis (BV)
- Anaerobic vaginal bacteria
- Gardnerella vaginalis
- Ureaplasma urealyticum (may be a possible cause)
(c) No cause found
In the event that no cause is identified for your PID, we recommend:
- Ensuring that a thorough STI screen has been undertaken
- Your partner has been screened for possible causes of PID and managed appropriately to reduce the risk of recurrence
Can I get PID even if I have protected sex?
Whilst consistent use of condoms significantly reduces the transmission of STIs, the risk is not completely eliminated. Sometimes condom splits may go unnoticed.
Additionally, there are non-STI causes of PID (e.g. Bacterial vaginosis) which account for a large proportion of cases of PID. This is why women in a stable relationship can have PID and is not necessarily a cause for relationship concern.
What can increase my chances of getting PID?
The following three things can increase your chances of getting PID:
(a) Risk of getting an STI
- If you have more than 1 sexual partner/ a new sexual partner
- Having unprotected sex
- If you are a sexually woman under 25
- Have had an STI before
- Having had PID before
(b) Risk of getting Bacterial vaginosis
(c) Undergoing gynaecological procedures which opens up the cervix
- Cervical procedures like cone biopsy / LLETZ
- Instrumentation through cervix (hysteroscopy)
- After miscarriage or termination of pregnancy
- Retained products of conception after an abortion
- Coil in situ
How is Pelvic Inflammatory Disease diagnosed?
We reach a diagnosis of PID after undertaking a thorough:
- Medical history
- Sexual history
- Physical examination (including pelvic examination)
- Swab for STI screen (Chlamydia, Gonorrhoea and Mycoplasma genitalium)
- High vaginal swab for bacterial culture
In some cases, we may recommend the following:
- Ultrasound scan for tubo-ovarian masses and fluid in the surrounding pelvic cavity
- Endometrial biopsy
- Blood test to assess inflammatory parameters
There is no unique test as such to look for PID (as there may be for Chlamydia).
Why is the diagnosis of PID often missed?
We can see at least three reasons for this:
- There is no unique test for PID
- Patients with PID may present with different symptoms
- There is limited training and education amongst non-specialist clinicians on PID
Can Pelvic Inflammatory Disease be treated?
Yes. However, there is a challenge in making a timely diagnosis to avoid any complication.
What is the treatment for PID?
The treatment offered depends on the cause of PID. This is in the form of oral antibiotics but may sometimes involve an intramuscular injection (e.g. if Gonorrhoea is the cause of PID).
Current practice is to combine 2 different antibiotics which cover different types of bacteria infections that cause PID.
You may follow the links below for more information on STI treatments:
Do I have to wait for my test results before starting treatment?
No. A diagnosis of PID is made based upon clinical grounds and treatment should be started without waiting for the test results. However, it is important that appropriate specimens are collected before starting the treatment.
In light of your test results, your clinician may adjust the required antibiotics.
How long does the treatment take to work?
The medications given to you should start to reduce the symptoms within a couple of days and completely resolve your symptoms by the end of your treatment.
How effective is the treatment for PID?
Treatments prescribed for PID are extremely effective. Your clinician may suggest a change in your antibiotics based on your test results and in light of any side effects you may experience.
If your symptoms have not gone away, your clinician will arrange further tests to find out the presence of another condition that may be responsible for your symptoms.
How long do I have to wait before having sex?
It is highly recommended to abstain from any sexual contact, even with a condom until both partners have completed the course of antibiotics. The usual period is two weeks to allow for your symptoms to get better, for the antibiotics to work and for your partner to have the test and treatment (though in some cases this time period may be longer).
What happens if I don’t get treated?
It is important to receive timely treatment for PID to relieve symptoms as well as to prevent future complications. Many cases of PID do not get diagnosed and treated as such which results in long term consequences including infertility, risk of ectopic pregnancy and chronic pelvic pain.
It is important that PID is ruled out in patients diagnosed with Chlamydia, Gonorrhoea, Mycoplasma genitalium and Bacterial vaginosis. This is because the usual dosage of antibiotics given for these infections is insufficient when they have associated PID.
Do I need to book a follow up appointment?
We recommend booking a follow up appointment after two weeks, if you have any ongoing symptoms or concerns.
Do I have to tell my partner if I am diagnosed with PID?
It is strongly recommended that your partner(s) are assessed for any underlying infections. This will help prevent reinfection to you in the future and another episode of PID.
In the cases where an STI test does come back positive, it is essential that your partners are informed. If you are unable to do this, then we can do so for you.
Of course, we will give you all the necessary support in conveying your diagnosis and answer any questions that you may have.
Page reviewed by Dr. Manoj Malu (Clinical Director)
Last reviewed date: 14 February 2021
Next review due: 14 February 2024
Whilst this content is written and reviewed by sexual health specialists, it is for general guidance only. It is not intended to replace the advice of your clinician.
References & Further Reading
- Public Health England: Rates of Pelvic Inflammatory Disease (PID) in England (2000-2013)
- NHS: Pelvic Inflammatory Disease
- Mayo Clinic: Pelvic Inflammatory Disease Symptoms
- CDC: Pelvic Inflammatory Disease
- The Journal of Infectious Diseases: Proportion of Pelvic Inflammatory Disease Cases Caused by Chlamydia trachomatis: Consistent Picture From Different Methods
- The Lancet: Intrauterine devices and pelvic inflammatory disease: an international perspective