Hydrophilic drugs carry a greater risk to the fetus than lipophilic because lipophilic drugs easily cross the placenta from the fetus back to the mother. But to the 3 rd trimester of pregnancy in fetal tissues begin accumulate and lipophilic drugs. Getting in the body of the fruit, medicines only small part linked to blood proteins, because of fetal blood is not enough. Thus in medication for his blood circulates in an active state and adversely affects the tissue child, and in particular on his brain. By the ability to injure effect on the fetus drugs are divided into 3 groups:

I group. Drugs with a high risk of damaging effect on the fetus, which processing my pregnancy necessarily require its termination:

immunosuppressants. These drugs act not only on the embryo, but also women (up to 6-12 months) and male (up to 3mes) germ cells until the period of conception, ie If azotioprim was appointed non-pregnant women of childbearing age, risk of damaging effect on the fetus in sluchaeberemennosti maintained during years since the end of dosing.

cephalosporin group of antibiotics (tsefadroksil, cefazolin, cephalexin, cephalothin, tsefapirin, cefixime tsefodizim, cefotaxime, tsefnodoksim, tsefradin, ceftazidime, tsefrtiakson, cefuroxime).

antifungal antibiotics (amphotericin B, mikogeptin, etc.).

cytotoxic agents (methotrexate, vincristine, fluorouracil, cyclophosphamide) cause of the metabolism of folic acid. Their use in early pregnancy leads to gibeliembriona, and later - to the deformation of the front part charepa and violation of its rate of ossification.

antitumor antibiotics (bleomycin, rubomitsin, epirubicin and others).