Table 2.

Adjusted Costs of Delivery Hospitalizations, by Rural and Urban Residence and SMM Status, 2012 to 2014^*

All Delivery Hospitalizations (Unweighted n = 2 167 876)‡	Weighted, Adjusted Predicted Cost Per Delivery Hospitalization (95% CI), $†
	All Patients	Rural	Urban	Differential Cost Cost(rural) = Cost(urban)§
Group 1: deliveries with no SMM indicators (Unweighted n = 2 136 550)	4469 (4425 to 4513)	4573 (4487 to 4659)	4452 (4406 to 4497)	122 (37 to 205)
Group 2: deliveries with any SMM indicators (Unweighted n = 31 326)||	11 532 (11 340 to 11 723)	12 212 (11 632 to 12 791)	11 432 (11 236 to 11 628)	780 (185 to 1375)
Group 2a: deliveries with 1 SMM indicator (Unweighted n = 26 752)||	9193 (9049 to 9337)	9721 (9250 to 10 192)	9107 (8951 to 9265)	613 (104 to 1123)
Group 2b: deliveries with ≥2 SMM indicators (Unweighted n = 4574)||	24 398 (23 615 to 25 182)	25 679 (22 917 to 28 441)	24 247 (23 473 to 25 020)	1432 (−1336 to 4200)

SMM = severe maternal morbidity.

^*All hospital charges were converted to costs using Healthcare Cost and Utilization Project Cost-to-Charge Ratios, and all cost data were converted to 2014 dollars based on Personal Health Care Index hospital care component.

^†All adjusted costs and cost differences were estimated with multivariable generalized linear model employing a gamma distribution with a log-link function and adjusted for age, race/ethnicity, income quartile, primary payer, delivery method, hospital bed size, hospital location/teaching status, hospital region, and total number of chronic conditions.

^‡Delivery hospitalizations with missing values in any control variables except race were excluded from all analyses (4.7%). Delivery hospitalizations with missing race were categorized as “unknown.”

^§Differential costs are in boldface for P < 0.05.

^||For groups 2, 2a, and 2b, the adjusted and differential costs were also adjusted for 18 individual SMM indicators (Table 3).