Adverse effect of tobacco use on pregnancy outcome: A multi-center hospital based study in Karachi, Pakistan

Background: The health risks of tobacco use are well established and numerous. Tobacco use is very common in Pakistan; about 34% of men and 12.5% of women use different forms of tobacco on a regular basis. A recent review on the effects of smoking on women’s health reported a higher rate of gynecological complications. Our study objectives were to assess the adverse effect of maternal tobacco consumption during pregnancy on birth outcomes and obstetric complications in Karachi, Pakistan.
Methodology: A multi-center hospital based case control study was conducted in Karachi, Pakistan. A random sample of 1275 women coming to the gynecology & obstetric department for delivery was interviewed. Cluster sampling design was employed to meet the objectives of this study. Cases were birth outcomes (preterm delivery, low birth weight, still birth, low APGAR score) and obstetric complications (antepartum hemorrhage, cesarean section etc).
Results: Data analysis was done by using SPSS version 16. Final multiple logistic regression analysis showed that after adjustment for age & slits in the kitchen, gravidity (adjusted OR= 0.8; 95% CI: 0.7-0.9), hospital booking (adjusted OR= 1.9; 95% CI: 1.3-2.8), complications during current pregnancy (adjusted OR= 2.7; 95% CI: 1.8-3.9), still birth (adjusted OR= 1.8; 95% CI: 1.2-2.8) and miscarriages (adjusted OR= 3.9; 95% CI: 2.3-6.8) were significantly associated with cases while tobacco use was found to be marginally significant. Interaction between our main exposure (tobacco use) and education level was found to be significant.
 Conclusion:
Our study suggests that women who had adverse pregnancy outcomes were more likely to have still births, miscarriages and complications during current pregnancy. This indicates that pre-natal care and health education during the antenatal period might help in preventing such adverse events. Further research into specific factors responsible for adverse birth outcomes and obstetric complications is warranted.