Context: The majority of studies indicate antibiotics do interfere with contraceptive pills, such as clinical studies that suggest the failure rate of contraceptive pills caused by antibiotics is very low (about 1%). In cases where antibacterials have been suggested to affect the efficiency of birth control pills, such as for the broad-spectrum antibacterial rifampicin, these cases may be due to an increase in the activities of hepatic liver enzymes' causing increased breakdown of the pill's active ingredients. Effects on the intestinal flora, which might result in reduced absorption of estrogens in the colon, have also been suggested, but such suggestions have been inconclusive and controversial. Clinicians have recommended that extra contraceptive measures be applied during therapies using antibacterials that are suspected to interact with oral contraceptives.

Question: Do antibiotics interact with birth control pills?
Answer: The majority of studies indicate antibiotics do interfere with contraceptive pills

Question: What percentage of birth control pill failure is attributed to antibiotics?
Answer: about 1%

Question: What are the potential effects on intestinal flora?
Answer: reduced absorption of estrogens in the colon

Question: Have these potential effects been proven through testing?
Answer: inconclusive and controversial

Question: What do physicians recommend to counteract this potential issue?
Answer: extra contraceptive measures

Question: What do antibiotics interfere with?
Answer: contraceptive pills

Question: What percent is the  failure rate of contraceptive pills?
Answer: about 1%

Question: Whhat does intestinal flora reduce?
Answer: absorption of estrogens

Question: In therapy, what does the antibacterial interact with?
Answer: oral contraceptives

Question: Do antibiotics mess with birth control pills?
Answer: antibiotics do interfere

Question: What is birth control failure rate due to antibiotics?
Answer: about 1%

Question: What should women do if they are using antibiotics and birth control pills?
Answer: extra contraceptive measures

Question: Do antibiotics interact with intestinal flora?
Answer: Unanswerable

Question: What percentage of birth control pill failure is attributed to estrogens?
Answer: Unanswerable

Question: What are the potential effects on antibacterials?
Answer: Unanswerable

Question: What do control pills recommend to counteract this potential issue?
Answer: Unanswerable

Question: What do oral contraceptives reduce?
Answer: Unanswerable