l am taking trimethoprim to prevent a urine infection and am also on yasmin (the birth control pill)

i had unprotected sex recently (stupid l know) and he pulled out before he finished.

im just wondering if l was still protected? i've heard it lowers the protection a little but not drastically.

please no silly:(

l am always on them for a urine infection and it does affect the pill your partner should use a condom while you are on these antibiotics please

There is nothing listed in the interactions but one of the adverse effects is gastro intestinal upset (not inevitable), so if you do get diarrhoea or vomiting from it there is a risk.
The FPA recommend using an extra method of protection when on the combined contraceptive pill even though the risk might only be a low one.