Drugs During Pregnancy and Lactation 2nd Ed

Most prescribers and users of drugs are familiar with the precautions given concerning drug use during the first trimester of pregnancy. These warnings were introduced after the thalidomide disaster in the early 1960s. However, limiting the exercise of caution to the first 3 months of pregnancy is both shortsighted and effectively impossible – first, because chemicals can affect any stage of pre- or postnatal development; and secondly, because when a woman first learns that she is pregnant, the process of organogenesis has already long since begun (for example, the neural tube has closed). Hence, the unborn could already be inadvertently exposed to maternal drug treatment during the early embryonic period (Figure 1.1). This book is intended for practicing clinicians, who prescribe medicinal products, to evaluate environmental or occupational exposures in women who are or may become pregnant. Understanding the risks of drug use in pregnancy has lagged behind the advances in other areas of pharmacotherapy. Epidemiologic difficulties in establishing causality and the ethical barriers to randomized clinical trials with pregnant women are the major reasons for our collective deficiencies. Nevertheless, since the recognition of prenatal vulnerability in the early 1960s, much has been accomplished to identify potential developmental toxicants such as medicinal products and to regulate human exposure to them. The adverse developmental effects of pharmaceutical products are now recognized to include not only malformations, but also growth restriction, fetal death and functional defects in the newborn