Table 3.

Results of Robustness Tests

	C-Section with Complications		CDMR
Specifications	Coefficient	Robust SE	Coefficient	Robust SE
Test 1: Ob/gyn fixed effects
Log of general fertility rate	−0.223	0.253	−0.341**	0.068
Log of lagged ob/gyns per 100 births	0.426	0.718	0.225	0.279
Test 2: Institutional fixed effects
Log of general fertility rate	−0.171	0.232	−0.169**	0.079
Log of lagged ob/gyns per 100 births	0.471	0.801	0.282	0.301
Test 3: Excluding women with prior history of c-section
Log of general fertility rate	−0.291	0.285	−0.681**	0.084
Log of lagged ob/gyns per 100 births	0.363	0.518	0.310	0.189
Test 4: Excluding women <34
Log of general fertility rate	−0.207	0.231	−0.588**	0.089
Log of lagged ob/gyns per 100 births	0.409	0.319	0.314	0.449
Test 5: Including CDMR with obstetric complications
Log of general fertility rate	−0.205	0.121	−0.454**	0.075
Log of lagged ob/gyns per 100 births	0.392	0.641	0.256	0.206

Notes. All multionominal probit regressions included a full set of time dummies.

Coefficients and robust SEs for other explanatory variables are available from the authors.

All estimations were clustered by city/county.

When hospital fixed effects or ob/gyn fixed effects were included in the model (tests 1 and 2), regional fixed effects were all dropped out because most providers did not move in the short run.

Tests 3–5 included a full set of regional dummies.

N=2,235,627 in tests 1 and 2.

N=1,921,815 in test 3 (313,812 cases excluded).

N=232,673 in test 4 (2,002,954 cases excluded).

N=2,241,980 in test 5.

^**p<.01.

CDMR, cesarean deliveries on maternal request; c-section, cesarean section; Ob/gyn, obstetrician and gynecologist.