Table 4. Mortality and Severe Maternal Morbidity (Per 10 000 Singleton Births) by Prepregnancy Body Mass Index, Washington State, 2004-2013^a.

Maternal Mortality and Severe Morbidityb	Underweight (n = 23 675)		Normal Weight (n = 353 212)		Overweight (n = 191 991)		Obese
							Class 1 (n = 97 040)		Class 2 (n = 46 320)		Class 3 (n = 31 392)
	No.	Rate per 10 000	No.	Rate per 10 000	No.	Rate per 10 000	No.	Rate per 10 000	No.	Rate per 10 000	No.	Rate per 10 000
Death	1	0.4	14	0.4	8	0.4	4	0.4	3	0.6	4	1.3
Antepartum hemorrhage with transfusion	29	12.2	227	6.4	168	8.8	68	7.0	32	6.9	14	4.5
Respiratory	29	12.2	327	9.3	198	10.3	112	11.5	63	13.6	81	25.8
Obstetric embolism	4	1.7	58	1.6	30	1.6	21	2.2	9	1.9	13	4.1
Amniotic fluid embolism	2	0.8	18	0.5	3	0.2	10	1.0	2	0.4	0	0.0
Blood clot embolism (VTE)	3	0.1	37	0.1	24	0.1	9	0.1	7	0.2	13	0.4
Thromboembolism or DVT	11	0.5	156	0.4	108	0.6	69	0.7	30	0.6	31	1.0
Cerebrovascular or CNS morbidity	23	9.7	225	6.4	144	7.5	97	10.0	41	8.9	42	13.4
Cerebral venous thrombosis	0	0.0	29	0.8	20	1.0	17	1.8	2	0.4	3	1.0
Cerebrovascular disorders in puerperium	2	0.8	29	0.8	9	0.5	9	0.9	2	0.4	4	1.3
Cardiac morbidity	12	5.1	134	3.8	103	5.4	51	5.3	26	5.6	44	14.0
Cardiac arrest or failure or MI	8	3.4	66	1.9	33	1.7	24	2.5	14	3.0	20	6.4
Peripartum cardiomyopathy	1	0.4	29	0.8	20	1.0	9	0.9	4	0.9	7	2.2
Eclampsiac	8	3.4	131	3.7	86	4.5	45	4.6	39	8.4	22	7.0
Severe postpartum hemorrhage with transfusion	113	47.7	1489	42.2	796	41.5	371	38.2	185	39.9	98	31.2
With coagulation defects	34	14.4	357	10.1	209	10.9	100	10.3	26	5.6	15	4.8
Sepsis	100	42.2	1140	32.3	661	34.4	357	36.8	191	41.2	126	40.1
Puerperal sepsis	86	36.3	962	27.2	567	29.5	300	30.9	166	35.8	101	32.2
Acute renal failure	6	2.5	38	1.1	40	2.1	21	2.2	13	2.8	11	3.5
Obstetric shock	6	2.5	56	1.6	25	1.3	12	1.2	10	2.2	7	2.2
DIC	9	3.8	84	2.4	37	1.9	23	2.4	7	1.5	4	1.3
Uterine rupture	10	4.2	188	5.3	105	5.5	67	6.9	30	6.5	22	7.0
Complications of anesthesia or obstetric interventions	37	15.6	528	14.9	343	17.9	197	20.3	101	21.8	77	24.5
Potentially lifesaving interventions	214	90.4	2530	71.6	1508	78.5	763	78.6	376	81.2	289	92.1
Hysterectomy	22	9.3	195	5.5	120	6.3	60	6.2	41	8.9	25	8.0
Blood or blood products transfusion	178	75.2	2101	59.5	1257	65.5	599	61.7	292	63.0	197	62.8
Respiratory (assisted ventilation)	11	4.6	95	2.7	74	3.9	47	4.8	24	5.2	41	13.1
ICU admission	28	12.0	259	7.4	164	8.7	83	8.7	46	10.1	59	19.1
Composite severe maternal morbidity or mortality	406	171.5	5057	143.2	3080	160.4	1629	167.9	826	178.3	637	202.9

Abbreviations: CNS, central nervous system; DIC, disseminated intravascular coagulation; DVT, deep venous thrombosis; ICU, intensive care unit; MI, myocardial infarction; VTE, venous thromboembolism.

^aUnderweight defined as body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) less than 18.5; normal weight as BMI 18.5 through 24.9; overweight as BMI 25.0 through 29.9; obese class 1 as BMI 30.0 through 34.9; obese class 2 as BMI 35.0 through 39.9; obese class 3 as BMI 40 or greater.

^bSevere maternal morbidity includes conditions presented in Table 1. Severe morbidity subtypes are not mutually exclusive (eg, women who had eclampsia and acute renal failure would be included both categories). Pulmonary thrombosis due to blood clot is included in both the respiratory morbidity and the thromboembolism categories.

^cDoes not include superimposed eclampsia.