Maternal Smoking Increases Risk of Placental Abruption
Smoking during first and second pregnancies associated with 11-fold increase in risk
TUESDAY, Aug. 7 (HealthDay News) -- Women who smoke during pregnancy have a greater risk of placental abruption than those who do not, researchers report in the August issue of the American Journal of Epidemiology.
Cande V. Ananth and Sven Cnattingius of the University of Medicine and Dentistry of New Jersey in New Brunswick, N.J., performed a population-based prospective cohort study of 526,690 women who delivered their first two consecutive births in Sweden in 1983-2001.
Women who smoked during pregnancy had double the risk of abruption in a second pregnancy (odds ratio, 1.8), but not the first pregnancy. Women who had an abruption in a first pregnancy had an 11-fold higher risk of abruption in a second pregnancy if she smoked (odds ratio, 10.9). However, women who had an abruption in a first pregnancy had a higher risk for abruption in the second pregnancy irrespective of their smoking history.
"These findings suggest that women who quit smoking before pregnancy may benefit from reduced risk of abruption," the authors conclude. "The observation that the recurrence of abruption is substantially increased regardless of changes in smoking habits suggests that factors other than smoking may influence the recurrence of placental abruption."