Lower back pain associated with vaginal discharge can point to an underlying condition when they occur together. However, these symptoms are common on their own.
Conditions that cause lower back pain and vaginal discharge include:
- Pelvic inflammatory disease (PID)
PID is caused by an infection in the upper genital tract. It can appear in the uterus, fallopian tubes, or ovaries. The disease can occur at any age, though it is most common in women under 25.
PID can cause:
- pelvic pain
- painful urination
- vaginal discharge to appear yellow or green
- Urinary tract infection (UTI)
Cystitis occurs when a UTI infects the bladder. When a UTI affects the urethra, the condition is called urethritis. When it is located in the kidneys, it is called a kidney infection.
Bacteria are most commonly responsible for UTIs, but fungi and viruses can also cause them.
UTIs can occur in people of any age, including children.
Symptoms of a UTI include:
- a burning sensation when urinating
- increased vaginal discharge
- frequent urge to urinate
- pelvic pain
- lower back pain
Gonorrhea is a sexually transmitted infection (STI). Symptoms do not appear immediately after transmission, and they may take several weeks to appear, thereby increasing the risk of spread among sexual partners.
Gonorrhea often goes untreated because of the delay in symptoms. This can cause serious health complications, including infertility. Most women with gonorrhea experience no symptoms. When present, symptoms can include discharge and pelvic pain, which may radiate to the lower back.
- Cervical cancer
Cervical cancer can cause lower back pain and unusual discharge in rare cases. Discharge may be pink with unpleasant odour. Cervical cancer also causes pelvic pain. Cervical cancer often has no symptoms in the initial stages. For this reason, it is important to have regular Pap smears.
- Reactive arthritis
This condition causes inflammation in the joints. Infection, including those transmitted sexually, can cause the symptoms.
Reactive arthritis can cause abnormal discharge and lower back pain, but the condition is not connected to serious health risks.
Lower back pain and abnormal vaginal discharge can indicate pregnancy. Vaginal discharge may increase in volume and otherwise change during this time.
Increased discharge helps to protect the womb from infection. Even more discharge may appear in the final few weeks of pregnancy.
Lower back pain is also common during pregnancy, especially as the baby grows heavier or moves. These actions can hit nerves that affect the back.
- Ectopic pregnancy
An ectopic pregnancy occurs when a fertilized egg attaches itself outside the uterus, usually to a fallopian tube. A doctor must remove the fertilized egg before it grows too large and causes internal damage.
An ectopic pregnancy can cause:
- pain in the rectum
- sharp abdominal cramping
- severe pain on one side that radiates to the back
Unprotected sexual activity is a major risk factor for conditions that can cause lower back pain and abnormal vaginal discharge.
Other risk factors include:
- poor hygiene
- not drinking enough water
- wiping from back to front after using the toilet
- taking birth control pills
- having a compromised immune system
However, it is not always possible to prevent the conditions listed above
A doctor will begin by asking about symptoms and a person’s medical and sexual history. The doctor will often request a urine sample, to detect infections such as UTIs. They may also use a swab to take a sample from the inside of the vagina. A lab will test the sample for signs of STIs, including gonorrhea.
Vaginal swabs and urine tests can also help to diagnose similar conditions, such as PID.
Treatment methods depend on the underlying cause. A doctor may prescribe antibiotics to treat UTIs and some STIs.
They may prescribe antifungal medications, as pills or creams, to treat vaginitis caused by yeast infections.
No treatment may be necessary if a person is experiencing lower back pain and unusual discharge during pregnancy. However, if the discharge comes with foul odor or pains, this can be a sign of an infection.
Ectopic pregnancies should receive immediate treatment. Doctors usually use a medication called methotrexate, and they may perform surgery to remove the fertilized egg.