Placental pathology differs by smoking status in abruption, intervillous thrombus more common in smokers

The placental pathology of women who have pregnancies complicated by abruption differs depending on smoking status, with intervillous thrombus more common in smokers and placental infarcts more common in non-smokers, researchers report in the September issue of the American Journal of Obstetrics and Gynecology.

Cande V. Ananth, PhD, from UMDNJ-Robert Wood Johnson Medical School in New Brunswick, NJ, and colleagues examined the effect of maternal cigarette smoking on placental histology in 189 women with abruption. Of these, 10.6% were self-reported smokers.

The researchers found that intervillous thrombus was significantly more common in smokers (20 vs. 3%, OR 17.5). There also tended to be more villous fibrosis in smokers (25 vs. 11.8%). In contrast, placental infarcts were significantly less common in smokers (10 vs. 32.5%, OR 0.20).

“These findings suggest that different pathologic mechanisms may be responsible for the histologic findings between smokers and non-smokers diagnosed with placental abruption,” Ananth and colleagues conclude.

Kaminsky LM, Ananth CV, Prasad V, et al. The influence of maternal cigarette smoking on placental pathology in pregnancies complicated by abruption. Am J Obstet Gynecol. 2007;197:275.e1-.e5.