What causes cystitis?
Cystitis is usually caused by bacteria. This happens if the bacteria from your poo gets into your urinary tract, through your urethra. Your urethra is the tube which carries urine out of your body. It happens more in women as a female's urethra is shorter than in men. Some things can increase your risk of getting bacteria in your urinary tract, such as having a weakened immune system or having sex.
What increases your risk of cystitis?
Some things could increase your risk of getting cystitis, such as:
- having a weakened immune system
- having diabetes
- being postmenopausal
- having a condition that makes it difficult to empty the bladder
- being pregnant
- having a condition that blocks the urinary tract, like kidney stones
- using spermicide with contraception
- having a urinary catheter, which is a tube used to drain urine from your bladder
- wiping your bottom from back to front after using the toilet
- having sex
According to this study, the risk of cystitis can increase by 10% for every day that a woman has a catheter and 3 to 4% in men.
The above risk factors could cause cystitis as they can affect the normal bacteria in your vagina, make it easier for bacteria to enter your bladder or make it more difficult for your body to fight cystitis. This study found that anything that affects normal vaginal bacteria can increase the risk of developing UTIs, such as menopause, pregnancy, and having sex.
What is recurrent cystitis?
Recurrent cystitis is where you get cystitis with symptoms twice or more in 6 months or 3 times or more in a year. Your doctor may check tests to find out why you are having recurrent cystitis and prescribe long term treatment to help prevent or treat recurrent cystitis, so you should always speak to a doctor if you keep getting cystitis.
Why do I keep getting cystitis?
Your body has natural defences to protect you against bacterial infections such as cystitis, including mildly acidic mucus in the vagina that prevents bacteria from growing and multiplying. If you keep getting cystitis, then it is likely that these natural defences are not working properly, or something is affecting your body’s ability to kill off the bacteria before it causes an infection. The most common causes of recurrent cystitis are:
- Bladder or kidney problems - bacteria is typically flushed from the body through urine, so if you have a condition that causes urine to stay in your body then that can increase your risk of an infection.
- Sex - having sex increases the chance of bacteria getting into the vagina and urinary tract, which can cause cystitis.
- Some contraceptives, especially the contraceptive diaphragm - this is more common if your diaphragm doesn’t fit correctly. These contraceptives typically use spermicide to protect against pregnancy, which can change the Ph balance of the vagina and kill off protective bacteria
- Hormonal changes - this is especially common during menopause or during pregnancy. A fall in oestrogen levels can reduce the amount of protective mucus in the vagina, which makes you more prone to infection.
Why do I get cystitis after intercourse?
When women have sex, the normal bacteria in their vagina can change. This can increase the risk of getting cystitis. Sex can also cause some bacteria to get into your urethra. The risk of cystitis can also be increased if you use spermicide with contraception. It’s best to pee as soon as possible after having sex to try to prevent cystitis.
Similarly, men are also at a higher risk of cystitis after sex, as bacteria may be able to get into the urethra. However, because a man’s urethra is longer, it is less likely for bacteria to be able to travel to the bladder and cause an infection.