The chance of pregnancy is minimal, almost zero, if the condom is used correctly. Zinnat is unlikely to be a debuff to Belara's effectiveness, but the extra protection eliminates it.

According to current scientific research, the only group of antibiotics for which a direct effect on the effectiveness of contraception has been proven are rifamycins (rifampicin, rifabutin, rifaximin). They stimulate enzymes in the liver that break down hormones contained in contraceptives (ethinylestradiol and progestogens), which reduces their concentration in the body and weakens the contraceptive effect. Scientific studies have not confirmed the negative effect of other antibiotics on the effectiveness of hormonal contraception. However, many experts believe that there are too few qualitative studies available to completely rule out the effect of antibiotics on the effectiveness of contraception. Therefore, it is often recommended to use an additional, barrier method of contraception (e.g. condoms) during antibiotic therapy and for 7 days after its completion.

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