THROMBOCYTOPENIA IN PREGNANT-WOMEN WHO USE COCAINE

OBJECTIVE: Our purpose was to determine the prevalence of cocaine-asso ciated thrombocytopenia. STUDY DESIGN: This cohort study was conducted in an inner-city prenatal center. A total of 1907 patients were scree ned by the Mother's Project, which is an intervention project for inne r-city cocaine-abusing parturients. Platelet counts were grouped by il licit drug usage. RESULTS: Platelet counts were available in 37% (709) of subjects; there were no differences between subjects with availabl e platelet counts and those without on illicit drug use or other demog raphic measures. Five groups were defined: drug-free group (n = 331), cocaine group (n = 104), cocaine and opiates group (n = 11), opiates g roup (n = 18), and other-drug group (n = 236). Nineteen subjects had a low platelet count (<150 x 10(9)/L). The medical records of all subje cts with a low platelet count were reviewed for any medical condition known to be associated with thrombocytopenia, and two subjects were ex cluded. The rate of thrombocytopenia in the drug-free group was 1.5%, whereas the rate in the cocaine group was 6.7% (relative risk 4.4, p < 0.05). Because of the reported association of thrombocytopenia with s eropositive human immunodeficiency virus status, seropositive women we re excluded from the analysis. Even after human immunodeficiency virus status adjustments for the estimated rate, the cocaine-using group co ntinued to have a significantly higher rate of thrombocytopenia (5.4% to 7.2% vs 1.23% to 1.26%, p < 0.05 to p < 0.005). CONCLUSIONS: These results indicate that cocaine use is an independent risk factor for th rombocytopenia in an inner-city parturient population.