Reports of cocaine-related obstetrical problems, including abruptio placentae and spontaneous abortion, have become increasingly evident in the medical literature; however, little is known about tissue distribution of cocaine in the pregnant woman. We report the toxicologic results of distribution studies performed on a pregnant woman and her fetus. Maternal/fetal cocaine concentration ratios were high when comparing blood (9:1), brain (6:5), and kidney (10:6). Possible explanations of the mechanism for lower fetal cocaine concentrations may include uterine vasoconstriction, incomplete maternal/fetal equalibration, or rapid placental/fetal clearance.