To determine if there is a difference in premature delivery (PTB) between African-American and Caucasian women who have undergone an ultrasound or physical exam indicated (rescue) cervical cerclage.
This was an IRB approved, retrospective cohort study of African-American (AA) and Caucasian women who underwent ultrasound and exam-indicated cervical cerclages. The study subjects were identified from a research quality perinatal database. All subjects received a vaginal cerclage utilizing a McDonald technique between 16 - 23 weeks of gestation. The primary outcome was spontaneous PTB; subdivided by gestational age as < 20 weeks, 20-23 weeks, 24-27 weeks, 28-31 weeks, 32-34 weeks and 35-36 weeks. Gestational age specific incidence of PTB was reported. Multivariable logistic regression was used to control for demographic and clinical differences between groups.
A cohort of 325 women was identified from 1997 to 2008; 215 African-American women (study group) and 110 Caucasian women (control group). AA women were significantly more likely to be obese (p<.0001), have Medicaid insurance (p<.01), a previous preterm delivery (p<.01) and be diagnosed with bacterial vaginosis (p<.05) or Chlamydia cervicitis (p<.05). There was no difference in the odds of delivery prior to 24 or 28 weeks of gestation between cohorts. The AA women were at significantly decreased risk of delivery prior to 28-31 weeks (19.5% vs.28.9% adj OR 0.53 [0.27 – 0.92]), 32-34 weeks (17.7% vs. 43% adj OR 0.29 [0.15 – 0.56]) and 34-36 weeks of gestation (28.4% vs. 43.2% adj OR 0.46 [0.27 - .79]) compared to the Caucasian women. The overall rate of preterm delivery was also significantly lower for the AA women. (66% vs. 81% adj OR 0.45 [0.27-0.8]
African-American women undergoing ultrasound and physical exam indicated cerclages experienced significantly lower rates of preterm birth less than 32, 34 and 37 weeks of gestation when compared to Caucasian women. This unexpected outcome was observed despite the number of risk factors for preterm birth in the African-American cohort.
© 2008 Mosby, Inc. Published by Elsevier Inc. All rights reserved.