Over the past decade, attention to clinical therapeutics has grown substantially from many different directions, including the important influences of gender differences and pregnancy [1–3]. Despite these advances there is increasing concern that discovery and development of new drugs for these important populations is lagging [4–9]. At the same time, recognition has grown that select populations are excluded from the drug development process, especially women and children [5, 10–12]. One consequence of this failure to specifically develop drugs for maternal and child health is to dissociate therapeutic opportunities for women and children from the drugs and treatments currently available. This distancing of women and children from drug development and therapeutic knowledge produces a host of clinical challenges for the concerned practitioner. In the absence of sufficient therapeutic knowledge, appropriate dosing is not known [13–17]. Without understanding of appropriate dosing, the clinician does not know if the dose recommended on the product label will produce the desired drug concentration at the site of action – or if the concentration produced will be above or below the needed concentration, producing toxicity or inadequate response, respectively. Similarly, without thoughtful therapeutic development in women and children it is not known if differences in pharmacodynamics will produce different treatment goals and needs for monitoring effectiveness and safety [14, 18–21].
A consequence of the failure to develop drugs for use in pregnancy is that most drugs are not tested for use during pregnancy [4, 22]; consequently, labeling, which may include extensive information about fetal safety [10, 23], includes nothing about dosing, appropriate treatment, efficacy, or maternal safety [3–5, 10, 11, 22, 23]. Yet these are concerns of health care providers considering treatment during pregnancy. Therefore, the practitioner treats the pregnant woman with the same dose recommended for use in adults (typically men) or may decide not to treat the disease at all. However, is the choice of not treating a woman during pregnancy better than dealing with the challenges which accompany treatment? Clearly treatment of depression poses risks for both mother and fetus, as does stopping treatment [24–26]. This is also the case with respect to influenza during pregnancy [13, 27, 28]. All combined, the state of therapeutics during pregnancy underscores the continued tension that exists between maternal–placental–fetal health and maternal quality of life during pregnancy and the lack of critical study of “gestational therapeutics”. This book hopes to address many of these imbalances.
Medical and health care providers caring for women during pregnancy have many excellent resources describing the safety of medications for the fetus [10, 23]. However, none of these references provide information on appropriate dosing as well as the efficacy of the various medications used during pregnancy for maternal/placental therapeutics. We are all familiar with the potential/actual costs, financial and psychosocial, of having treatments which produce developmental toxicity – however, how many of us ever think critically about the costs of having inadequate therapeutic options to treat the major diseases of pregnancy; growth restriction, pregnancy loss, preeclampsia/eclampsia. Where we have effective treatments for maternal disease – infection, depression, diabetes, hypertension – we are recognizing that continuation of treatment during pregnancy carries benefit for mother, placenta, and baby. In the end what is important for the mother, baby, and family is the appropriate balancing of benefit and risk – as indeed is the important balancing for all clinical therapeutics [11, 12]. This book provides medical and health professionals involved in the care of pregnant women with contemporary information on clinical pharmacology for pregnancy. It covers an overview of the impact of pregnancy on drug disposition, summarizing current research about the changes of pharmacokinetics and pharmacodynamics during pregnancy. This is followed by specific sections on the treatment, dosing and clinical effectiveness of medications during pregnancy, providing health care providers with an essential reference on how to appropriately treat women with medications during pregnancy. At one level the question is simple – how to treat, how to monitor for benefit and risk, how to know if treatment is successful? This book was developed to explore that question for women during pregnancy. The book is meant to be a guide to clinicians who care for women during pregnancy – we hope the busy clinician and student of obstetrics will find this a useful guide.
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