The objective of this paper is to assess whether increases in Medicaid coverage of smoking cessation services reduced smoking before, during, and after pregnancy, and improved birth outcomes.  Pooled cross-sectional, time series data for 179,854 women with live births insured by Medicaid between 1996 and 2008 in 34 states plus New York City were used to analyze self-reported smoking pre-pregnancy (3 months prior), during the last 3 months of pregnancy and postpartum (3-4 months); infant birth weight and gestational age at delivery.  Maternal socio-demographic and behavior variables from survey data and birth outcomes from vital records were merged with annual state data on Medicaid coverage for nicotine replacement therapies (NRT), non-NRT medications and cessation counseling.  Probit regression models were used to test associations between Medicaid cessation coverage and maternal smoking and birth outcomes.     

We find that Medicaid coverage of NRT and non-NRT medications was associated with 1.6 percentage point reduction (p<.05) in pre-pregnancy smoking among Medicaid insured women. Combining NRT and medication with counseling coverage increased this effect to 2.5 percentage points (p<.10).   Medicaid cessation coverage during pregnancy was associated with a small increase (<1 day) in infant gestation (p<.05).   Medicaid coverage of smoking cessation affects primarily those women enrolled prior to pregnancy.   Expansions of Medicaid eligibility and mandated coverage of some cessation services without co-pays under health reform could reduce pre-pregnancy smoking.