BACKGROUND AND PURPOSE:

• Both preterm birth and low birth weight are associated with adverse infant outcomes such as
  • Increased risk of mortality
  • Chronic health conditions
• Black women are at higher risk while risks for Hispanic population are similar to non-Hispanic white population
• Medicaid expansion under the Affordable Care Act allows states to extend coverage to low-income women regardless of pregnancy status, which may lead to reduced infant mortality
• Brown et al. (JAMA, 2019) studied whether Medicaid expansion has impacted rates for low birth weight or preterm outcomes

METHODS:

• Observational study (data from 2011-2016)
• Participants
  • Singleton live births to women
  • ages ≥19
• Data
  • Population-based data from the National Center for Health Statistics Birth Data Files
• Group designation by
  • State Medicaid expansion status
  • Racial/ethnic category
• Analysis
  • Compare birth outcomes among infants in Medicaid expansion states and non-Medicaid expansion states
  • Compare changes in relative disparities among racial/ethnic minorities
• Primary outcomes (dependent variables)
  • Preterm birth (<37 weeks) and very preterm birth (<32 weeks)
  • Low birth weight (<2500 g) and very low birth weight (<1500 g)

RESULTS:

• 15,631,174 births
• Racial/ethnic category
  • White infants: 8,244,924
  • Black infants: 2,201,658
  • Hispanic infants: 3,944,665
• Features of states with Medicaid expansion
  • Higher median incomes | Lower percentage of uninsured females | Higher percentage of minority females | Higher number of primary care physicians | Higher percentage of adults who had their cholesterol checked in the last 5 years | Higher percentage of first trimester prenatal intake
• Medicaid-expansion status
  • 18 states with expansion: 8,530,751
  • 17 states without expansion: 7,100,423
• There was no significant change in any of the primary outcomes overall between expansion and non-expansion states

• Preterm birth (prexpansion to postexpansion); P = .98
  • Expansion state: From 6.80% to 6.67%
  • Non-expansion state: From 7.86% to 7.78%
• Very preterm birth; P = .37
  • Expansion state: From 0.87% to 0.83%
  • Non-expansion state: From 1.02% to 1.03%
• Low birth weight; P = .20
  • Expansion state: From 5.41% to 5.36%
  • Non-expansion state: From 6.06% to 6.18%
• Very low birth weight; P = .14
  • Expansion state: From 0.76% to 0.72%
  • Non-expansion state: From 0.88% to 0.90%
• However, when data was broken out by race, differences between black infants compared to white infants was reduced in expansion states for all primary outcomes, indicated by a negative difference-in-difference-in-difference coefficient
  • Preterm birth (10.21% to 9.61%): −0.43 percentage points [95% CI, −0.84 to −0.02], P = .05
  • Very preterm birth (1.97% to 1.81%): −0.14 percentage points [95% CI, −0.26 to −0.02], P = .03
  • Low birth weight (9.96% to 9.50%): −0.53 percentage points [95% CI, −0.96 to −0.10], P = .02
  • Very low birth weight (1,82% to 1.69%): −0.13 percentage points [95% CI, −0.25 to −0.01], P = .04
• This benefit in Medicaid expansion was not seen for Hispanic infants

CONCLUSION:

• There was no statistical difference overall between states that did and did not expand Medicaid
• However, when refining the analysis based on race, there was a significant decrease in disparities in preterm birth or low birth weight for black infants
• The authors state

The findings here suggest that earlier and continual access to insurance coverage may provide an important opportunity for improving infant outcomes.

Learn More – Primary Sources:

Association of State Medicaid Expansion Status With Low Birth Weight and Preterm Birth

Related ObG Topics:

Disparities and the Management Patterns Over Time for Ectopic Pregnancy

Updated Outcomes Data for Neonates less than 500 Grams at Birth

Is There an Association Between High or Low Weight Gain and Maternal and Infant Outcomes?