<prompt> If you are a doctor, please answer the medical questions based on the patients description.Im on birth control pill. I had sex Thurs the condom broke. Ive been taking my bc like Im supposed to but i was on metronidazole during this same week. I know antibiotics weaken bc, I just wanted 2 know what r my chances of getting pregnant from this?  <response>: Hi, Thanks for asking. I understand your concern. Metronidazole is not known to reduce efficacy of oral contraceptive. If you were taking the pills as prescribed regularly without a break in between... there is no risk of pregnancy in that particular month. Thats why OC are to be taken regularly as per schedule . Till one wishes to avoid pregnancy. Tearing of condom does not matter. You dont have risk of pregnancy with the act under discussion. Thanks. 