Maternal asthma and risk of preterm delivery.
OBJECTIVE
We studied the relation between maternal history of asthma and preterm delivery.


METHODS
The 312 preterm delivery cases, studied in aggregate, and in subgroups (spontaneous preterm labor, preterm premature rupture of membranes, medically induced preterm delivery), were compared with 424 randomly selected women who delivered at term. Maternal medical records provided information on maternal lifetime asthma status, pregnancy outcome, and sociodemographic characteristics. Using multivariate logistic regression, we derived maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI).


RESULTS
Maternal history of asthma was associated with an increased risk of preterm delivery overall (OR = 2.37; 95% CI 1.15-4.88). Analyses of preterm delivery sub-groups indicated that maternal history of asthma was associated with at least a doubling in risk of spontaneous preterm labor (OR = 2.35; 95% CI 0.84-6.58) and medically induced preterm delivery (OR = 2.69; 95% CI 1.11-6.53), though only the latter approached statistical significance. There was some evidence of a modest association between maternal asthma and risk of preterm premature rupture of membranes (OR = 1.63; 95% CI 0.50-5.33).


CONCLUSIONS
These results support the hypothesis that maternal asthma is associated with an increased risk of preterm labor and delivery.
Sorensen
Tanya K
TK
Center for Perinatal Studies, Swedish Medical Center, Seattle, WA 98122, USA.
Dempsey
Jennifer C
JC
Xiao
Rong
R
Frederick
Ihunnaya O
IO
Luthy
David A
DA
Williams
Michelle A
MA
D000328:Adult; D001249:Asthma / Q000453:epidemiology*; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000453:epidemiology*; D006801:Humans; D016013:Likelihood Functions; D016015:Logistic Models; D007752:Obstetric Labor, Premature / Q000453:epidemiology*; D016017:Odds Ratio; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D012307:Risk Factors