Research Highlights Featured Chart

May 8, 2023

Delivery practices and newborn health

What impact do C-sections have on infant health outcomes?

Tyler Smith

Source: Prostock-studio

Rising rates of Cesarean sections in the United States and other countries have many women worried and confused about the best delivery option for them and their babies. But the effects of C-sections on infant health are not well understood.

In a paper in the American Economic Journal: Economic Policy, authors David Card, Alessandra Fenizia, and David Silver found mixed evidence on the impact of C-sections on newborn health outcomes.

They compared infants born in hospitals with relatively high versus low rates of C-sections, using an instrumental variables (IV) approach based on distance to hospitals. Their data come from California’s Office of Statewide Health Planning and Development and include patient discharge, emergency department, ambulatory surgery center, and vital statistics records for all in-hospital births between 2007 and 2011.

Figure 3 from the authors’ paper shows the likelihood of infants being readmitted or taken to the emergency department following their day of birth.

Figure 3 from Card et al. (2023)

Panel A shows that hospitals with lower rates of C-sections (red circles) have higher probabilities of readmission compared to hospitals with higher rates of C-sections (blue diamonds), especially in the first month after birth. The yellow triangles plot the IV estimates. The pattern shown is consistent with other studies indicating that delivery practices that prolong labor lead to lower C-section rates but more neonatal complications.

Panel B shows that the cumulative probabilities of an emergency department visit after birth exhibit a much different pattern. Initially, there is little difference between babies born in hospitals with high compared to low rates of C-sections. But a few months after birth, hospitals with high rates of C-sections see more emergency department visits, and that probability continues to rise throughout the first year of life. Most of these emergency department visits were for respiratory-related problems, which is consistent with a large number of observational studies linking C-sections to respiratory issues.

Overall, the findings suggest that infants delivered via C-section are born in better shape. But these infants are more likely to develop health problems that lead to emergency department visits within the first year of their lives.