You shouldn’t take antibiotics because they mess with your birth control
OTAKUPHOTO/Shutterstock According to Anate Brauer, MD, attending physician, Greenwich Hospital and NYU Medical Center, there is really only one antibiotic, Rifampin, that has been shown to decrease the efficacy of hormonal contraception such as estrogen delivered through a ring or patch. “While there are many reports of failed contraception while taking antibiotics, Rifampin is really the only one antibiotic that has been shown to increase activity of these liver enzymes, thereby making this method of contraception less effective,” she says. “If you are prescribed Rifampin, or any other medication that increases metabolism of hormonal contraception (some anti-fungals, anti-seizure medications and even some herbal supplements such as St. John’s Wart), use a form of barrier protection such as condoms.”
(Watch for the nine signs you’re on the wrong birth control.)
You cannot get pregnant while you are on the pill
S. Bonaime/Shutterstock When taken properly, oral contraceptives are very effective—but not 100 percent effective, explains Dr. Brauer. “Oral contraceptive pills contain estrogen, which keeps your body from growing an egg and ovulating,” she says. “If you are on ‘inactive’ pills for too long or miss pills, it is possible to have an ‘escape ovulation,’ meaning your body has had a long enough break from the active pills to grow an egg and ovulate it.” Escape ovulations are less common if you take active pills continuously or if the inactive pill window is shorter—four days versus seven with some pills. if you are late starting your active pills, or have missed pills, she recommends using a secondary form of contraception such as condoms.