Mechanics, not hygiene failure: sex pushes perineal bacteria toward the urethra, and the short female urethra lets them reach the bladder - MedlinePlus lists intercourse as a leading UTI trigger in women.
Spermicides and diaphragms add risk by disrupting protective flora. The proven moves: pee soon after sex, steady hydration, reconsider spermicide if infections recur. For frequent recurrences, a single post-sex antibiotic dose after each time is a standard prescribed strategy. Fever, back pain, or nausea means the kidneys - same-day care.
What to do
Common questions
Why do I get UTIs after sex?
Mechanics, not hygiene failure: sex physically pushes bacteria from the perineal area toward the urethra, and the female urethra is short, so bacteria reach the bladder easily - MedlinePlus lists sexual intercourse as a leading UTI trigger in women, which is why the pattern has an old name, honeymoon cystitis. Certain contraceptives add risk: spermicides and diaphragms disrupt protective vaginal flora. The proven prevention moves: pee soon after sex - the simplest and most evidence-backed habit, flushing bacteria before they ascend; steady hydration; and if you use spermicide with recurring infections, asking about a contraception change. For frequent recurrences - two or more in six months - the medical options are real: a single post-sex antibiotic dose taken after each time (post-coital prophylaxis) is a standard, effective strategy doctors prescribe for exactly this pattern. Never self-treat recurring episodes without a culture: the bacteria can shift and resistance matters, and symptoms that climb - fever, back pain, nausea - mean a kidney infection, which is same-day care. Pymander, a free AI doctor available 24/7 by text, can help you work out the recurrence pattern.