Epidemiology of medications use in pregnancy.

The use of prescribed and over-the-counter medications in pregnancy is on the rise. Many women become pregnant at an older age and with preexisting medical conditions that require pharmacotherapy. In addition, pregnancy is associated with profound changes in the physiology of virtually every organ in the body, which affect medications' pharmacokinetics and pharmacodynamics. Despite all of these, pregnant women are still considered therapeutic orphans, as the majority of current therapeutics were never studied in pregnancy. The goals of this review are to synthesize the available information regarding the epidemiology of medications use and the state of drug research in pregnancy, in an effort to highlight the need for pharmacologic research in pregnancy.