During pregnancy, antibiotic therapy should be aimed at eliminating infection, preventing infection of the fetus and newborn, as well as the development of postpartum HDS. The rational and effective use of antibiotics during pregnancy involves the following conditions:
• it is necessary to use drugs only with established safety of use in pregnancy, with known metabolic pathways (FDA criteria);
• when prescribing drugs should take into account the period of pregnancy, you must be especially careful in the appointment of antimicrobial drugs in the first trimester of gestation
• in the course of treatment, careful monitoring of the state of the mother and fetus is necessary.
The FDA divides all drugs into the following risk categories:
• category A – as a result of adequate strictly controlled studies there was no risk of adverse effects on the fetus in the first trimester of pregnancy (and there is no evidence of such a risk in subsequent trimesters);
• category B – the study of reproduction in animals did not reveal the risk of adverse effects on the fetus, and adequate and strictly controlled studies in pregnant women have not been conducted;
• category C – the study of reproduction in animals revealed an adverse effect on the fetus, and adequate and strictly controlled studies in pregnant women have not been carried out, but the potential benefits associated with the use of drugs in pregnant women may justify its use, despite the possible risk;
• category D – there is evidence of the risk of adverse effects of drugs on the human fetus, obtained during research or in practice, but the potential benefits associated with the use of such drugs in pregnant women may justify use, despite the possible risk;
• category X – animal tests or clinical trials have revealed abnormal development of the fetus and / or there is evidence of the risk of adverse effects of the drug on the human fetus, obtained during research or in practice, this category includes drugs that cause irreversible and severe fetal abnormalities, these drugs are contraindicated in pregnant women or women who may become pregnant.
According to this classification, all the antibiotics penicillin group, cephalosporins, erythromycin, azithromycin, metronidazole, meropenem, nitrofurans and antifungal drugs (nystatin, amphotericin B) included in Category B, tobramycin, amikacin, kanamycin, streptomycin, and tetracycline – known to the category D. that aminoglycosides can have an oto- and nephrotoxic effect on the fetus. Chloramphenicol is classified as C, as well as trimethoprim, vancomycin and fluoroquinolones.
Given the side effects of antimicrobial drugs on the mother, fetus and newborn, these drugs are divided into 3 groups.
Group I includes antibiotics, which are contraindicated during pregnancy. It includes chloramphenicol, tetracycline, trimethoprim, i.e. substances having an embryotoxic effect. This group includes fluoroquinolones, in which the effect on the cartilage tissue of the joints was found experimentally. However, their effect on the human fetus has been little studied.
Group II includes antibiotics, which during pregnancy should be used with caution: aminoglycosides, sulfonamides, nitrofurans, as well as a number of antibacterial drugs whose effects on the fetus have not been studied enough. Preparations of this group are prescribed for pregnant women only according to strict indications in case of serious diseases, the pathogens of which are resistant to other antibiotics, or in cases when the treatment is ineffective.