Risk of preterm delivery in relation to vaginal bleeding in early pregnancy.
OBJECTIVE
To examine the relationship between vaginal bleeding during early pregnancy and preterm delivery.


METHODS
Study subjects (N=2678) provided information regarding socio-demographic, biomedical, and lifestyle characteristics. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI).


RESULTS
Any vaginal bleeding in early pregnancy was associated with a 1.57-fold increased risk of preterm delivery (95% CI: 1.16-2.11). Vaginal bleeding was most strongly related with spontaneous preterm labor (OR=2.10) and weakly associated with preterm premature rupture of membrane (OR=1.36) and medically induced preterm delivery (OR=1.32). As compared to women with no bleeding, those who bled during the first and second trimesters had a 6.24-fold increased risk of spontaneous preterm labor; and 2-3-fold increased risk of medically induced preterm delivery and preterm premature rupture of membrane, respectively.


CONCLUSIONS
Vaginal bleeding, particularly bleeding that persists across the first two trimesters, is associated with an increased risk of preterm delivery.
Hossain
Rydhwana
R
Department of Epidemiology, Multidisciplinary International Research Training Program, University of Washington, School of Public Health and Community Medicine, Seattle, WA 98195, USA.
Harris
Tenecia
T
Lohsoonthorn
Vitool
V
Williams
Michelle A
MA
D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007752:Obstetric Labor, Premature; D016017:Odds Ratio; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014592:Uterine Hemorrhage