Misoprostol is a synthetic prostaglandin E1 analog used therapeutically for the prevention of nonsteroidal anti-inflammatory drug-induced gastric ulcers. The package label contains a black box warning stating that “misoprostol administration to women who are pregnant can cause abortion, premature birth, or birth defects”. Mortality, of course, was a feature in many cases, and growth retardation was the only class of developmental toxicity not affected by misoprostol. Misoprostol is a large hydrophobic compound. It can participate in hydrogen bonding both as an acceptor and a donor. It is of average polarity with respect to the other human developmental toxicants. The drug has been marketed for use in humans since 1986. It was misused beginning in the early 1990s in Brazil as an abortifacient due to its availability over the counter; it was subsequently banned and fell into black market use.