Miscarriage (spontaneous abortion) is the most common adverse outcome of pregnancy. The use of illicit drugs has been implicated as a factor. This study examined the associations between cocaine use and tobacco use and spontaneous abortion among pregnant adolescents and women (aged 14-40).
The components of tobacco smoke are understandably dangerous to an expectant mother and her unborn child: Nicotine, the main addictive compound of tobacco smoke, is also a strong vasoconstrictor that reduces uterine and placental blood flow. Other toxic components of tobacco smoke include carbon monoxide, which binds to the hemoglobin and decreases the availability of oxygen to the fetus, and cyanide, which depletes vitamin B12, a necessary factor in fetal growth and development.
Cotinine (the principal metabolite of nicotine) was detected in the urine of a significantly larger percentage of the 400 subjects who had spontaneous abortions. The results showed that cigarette smoking accounted for twice the incidence of spontaneous abortions as cocaine use.
Ness RB, Grisso JA, Hirschinger N, et al. Cocaine and tobacco use and the risk of spontaneous abortion. The New England Journal of Medicine, Feb. 4, 1999; vol. 340, no. 5, pp333-39.