Spotting the difference: UTIs and STIs

It’s easy to see why people get confused when it comes to urinary tract infections (UTI) and sexually transmitted infections (STIs). After all, both involve genitals and they can share some similar symptoms.

But it’s important you understand the difference so that you know when it’s time to see a doctor.

Let’s learn about UTIs and STIs, the signs and symptoms you should look out for, and what you can do to prevent them.

Your urinary tract is made up of the tube you pee from (urethra), your bladder, the tubes that connect your bladder to your kidneys (ureters), and your kidneys. A UTI is an infection in any part of this system.1

Affecting more than 150 million people every year, most UTIs are caused by bacteria from the skin around your genitals or anus entering your urinary tract.1 2 It’s possible to get a UTI after sex, but that doesn’t mean it’s necessarily an STI.1

Several common bacteria can cause UTIs, but Escherichia coli and Klebsiella pneumoniae are the most common culprits.3 E. coli is responsible for up to 95% of UTIs alone.3

• burning sensation while peeing
• more frequent peeing than usual
• cloudy urine, although infection is still possible if urine is clear
• slight pain in the lower abdomen or pelvis
• no abnormal discharge
• Blood in your pee is more common in UTIs but can be a symptom of some STIs.

• If your symptoms are mild and you don’t have a fever, keep well hydrated. Aim for 2–3 liters of water a day, but no need to overdo it.
• If your symptoms persist after 24 hours or you experience fever, chills, or nausea, see your doctor.
• Try not to hold in your pee, even if it hurts. 
• It’s common for people with vaginas to get UTIs now and then, as their urethras are shorter.4 But if they occur very frequently or become severe, you should see your doctor.

STIs are generally transmitted through unprotected sexual contact with an infected partner.5 However, it's also possible to be infected when you use protection.6

They are also very common: more than 1 million STIs are acquired every day worldwide.5

There are more than 30 known bacteria, parasites, and viruses that can cause STIs. The 8 most common STIs are:5

• chlamydia 
• gonorrhea
• syphilis
• trichomonas vulvovaginitis
• herpes
• HIV
• hepatitis B
• HPV.

Some STIs can share symptoms with UTIs, such as burning while peeing and pain in the lower abdomen.

• abnormal discharge from your vagina or penis
• genital blisters or rash
• pain during intercourse
• itchiness
• lumps in the groin
• heavier, more painful periods or bleeding outside your normal periods

It’s important to know you can have an STI and a UTI at the same time.

• See your doctor. Bear in mind that STIs may not cause symptoms straight away.
• If you do have an STI, inform any recent sexual partners so they can get tested too.

There are precautions you can take to reduce your risk of catching UTIs and STIs.

• Wipe from front to back after going to the toilet, especially if you have a vagina.
• Pee within 20 minutes after vaginal sex.
• Drink plenty of water so that fluid is always moving through your system.

• Use a condom. However, nothing is 100% safe. If you’re concerned you might have an STI, even after safe sex, check with your doctor.

At the clinic, your doctor may ask you questions like ‘Did you use a condom?’ or ‘Did you have multiple sexual partners?’ It's not so they can judge you. It’s so they can organize what further tests you need. So, don’t be shy or feel ashamed about your answers.