Association between tobacco use in pregnancy and placenta-associated syndromes: a population-based study.
BACKGROUND
Cigarette smoking is an established risk factor for adverse perinatal outcomes. The purpose of this study is to examine the association between maternal smoking in pregnancy and the occurrence of placental-associated syndromes (PAS).


METHODS
We analyzed data from a population-based retrospective cohort of singleton deliveries that occurred in the state of Missouri from 1989 through 2005 (N = 1,224,133). The main outcome was PAS, a composite outcome defined as the occurrence of placental abruption, placenta previa, preeclampsia, small for gestational age, preterm or stillbirth. We used logistic regression models to generate adjusted odd ratios and their 95 percent confidence intervals. Non-smoking gravidas served as the referent category.


RESULTS
The overall prevalence of prenatal smoking was 19.6%. Cigarette smoking in pregnancy was associated with the composite outcome of placental syndromes (odds ratio, 95% confidence interval = 1.59, 1.57-1.60). This association showed a dose-response relationship, with the risk of PAS increasing with increased quantity of cigarettes smoked. Similar results were observed between smoking in pregnancy and independent risks for abruption, previa, SGA, stillbirth, and preterm delivery.


CONCLUSIONS
Maternal smoking in pregnancy is a risk factor for the development of placenta-associated syndrome. Smoking cessation interventions in pregnancy should continue to be encouraged in all maternity care settings.
Aliyu
Muktar H
MH
Department of Preventive Medicine, Institute for Global Health, Vanderbilt University, Nashville, TN, USA.
Lynch
O'Neil
O
Wilson
Ronee E
RE
Alio
Amina P
AP
Kristensen
Sibylle
S
Marty
Phillip J
PJ
Whiteman
Valerie E
VE
Salihu
Hamisu M
HM
D000328:Adult; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D016015:Logistic Models; D008923:Missouri / Q000453:epidemiology; D010922:Placenta Diseases / Q000453:epidemiology / Q000209:etiology*; D011225:Pre-Eclampsia / Q000453:epidemiology / Q000209:etiology*; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology / Q000209:etiology; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D050497:Stillbirth