Medicaid and preterm births in Virginia: an analysis of recent outcomes

The study objectives were to evaluate adequacy of prenatal care and risk for preterm birth among Medicaid clients in Virginia and to determine if payment method is associated with the risk of preterm birth.

Birth certificate data for the Commonwealth of Virginia for 2007 and 2008 were linked with Medicaid claims data. Analysis was limited to singleton births. Three payment methods were evaluated: private insurance, self-pay, and Medicaid. The prevalence of preterm birth for each level of prenatal care defined by the Kotelchuck prenatal care index was assessed for each payment method. Unconditional logistic regression modeling was used to assess the association between payment method and preterm birth risk while controlling for known preterm birth risk factors.

Preterm birth prevalences (95% confidence interval [CI]) for the different payment methods were 7.9% (4.79-8.07) for the privately insured, 10.1% (9.57-10.60) for the self-pay group, and 10.2% (9.95-10.45) for Medicaid recipients. Compared with those with private insurance, women on Medicaid had an adjusted odds ratio (OR) for preterm birth (95% CI) of 0.99 (0.94-1.03). Self-pay mothers had a 32% increase in the odds of preterm birth relative to the privately insured. All payment groups show a trend toward significant reduction in preterm birth prevalence as adequacy of prenatal care improved from inadequate to adequate. Medicaid enrollees had a high prevalence of known risk factors, including smoking and illicit drug use and cervical insufficiency.

When known risk factors have been controlled, preterm birth risk for Medicaid enrollees did not differ significantly from the privately insured.