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Disentangling Sources of Variation in C-Section Rates
(Forthcoming Article) - Cesarean section rates vary widely across U.S. counties, but whether this variation
reflects patients’ medical risk, beliefs, and preferences or obstetric care environments,
including clinicians’ practice styles and delivery facilities, remains unclear.
Using 1989–2019 U.S. birth records, we study closures of counties’ last operating obstetric
units, which redirect mothers to counties with different baseline C-section
rates. In an instrumental variables framework, we find that a one-percentage-point
increase in the delivery county’s C-section rate raises a mother’s C-section probability
by approximately one percentage point, highlighting the central role of where
mothers receive obstetric care in determining C-section use.