Pharmacotherapy in pregnancy

Abstract

Between 1958 and 1961 approximately 10,000 children with severe limb defects were born, whose mothers had taken the somnifacient thalidomid. Since then, pharmaceutical agents in pregnancy are applied with legitimate caution by the pharmaceutical industry, physicians and patients, although often accompanied by irrational panic. According to statistical inquests, 15 to 50 percent of expectant mothers take pharmaceutical agents in the first trimester of pregnancy, often being not aware of their pregnancy. Considering the sensitive phase of organogenesis, the consequences may be particularly fatal in the first three months of pregnancy. After thalidomid more teratogenic pharmaceutical agents were discovered, i.e. coumarin derivates (e.g. warfarin), vitamin A and its derivates (e.g. isotretinoin), antifolates or anticonvulsants such as hydantoin or valproic acid. A number of other drugs are supposed to be potentially embryotoxic/fetotoxic, the effect of those pharmaceutical agents above all depending on dose and time of exposure. Case reports on malformations are available for numerous drugs, but studies with statistical validity are often missing. The pharmaceutical industry takes a legally safe position noting "contraindication" or at least "strict indication" in the consumer information. Concerning expectant mothers with chronic diseases like epilepsy, hypertension or bronchial asthma a therapeutic nihilism may lead to a dramatic deterioration of the disease, thereby causing high risks in fetal development. On the other hand numerous abortions without profound indications are carried out due to insufficient information of patients and medical staff on the real risks of a medication during early pregnancy. On principle reliable drugs should be preferred to new agents during fertile age of women. Special information centres for reproductive toxicology with corresponding data banks should be established and consulted, if an exposure with an insufficiently tested substance has taken place in ignorance of pregnancy.