Epidemiology of Emergency Medical Services-Attended out-of-Hospital Deliveries and Complications in the United States

Figures & data

Figure 1. Flow chart.

Table 1. Patient and incident of EMS activations.

	Maternal
	Overall (n = 10,243)	Out-of-hospital delivery (n = 8,614)	Delivery complications (n = 1,712)	Newborn Overall (n = 5,749)
Maternal age in years, median (IQR)	28 (23, 32)	28 (23, 32)	29 (24, 34)	n/a
Maternal age categories, n (%)
12–19 years	812 (8)	704 (8)	112 (7)	n/a
20–34 years	7,761 (76)	6,581 (76)	1,238 (72)
35–50 years	1,670 (16)	1,329 (15)	362 (21)
Day of week, n (%)
Weekday	7,483 (73)	6,277 (73)	1,270 (74)	4,117 (72)
Weekend	2,760 (27)	2,337 (27)	442 (26)	1,632 (28)
Time of day, n (%)
Day (0600–1759)	4,991 (49)	4,144 (48)	880 (51)	2,860 (50)
Night (1800–0559)	5,252 (51)	4,470 (52)	832 (49)	2,889 (50)
Level of service/response, n (%)
Basic life support	1,576 (15)	1,248 (14)	341 (20)	757 (13)
Advanced life support	8,667 (85)	7,366 (86)	1,371 (80)	4,992 (87)
Location where patient found, n (%)
Home/residence	7,441 (73)	6,328 (73)	1,178 (69)	3,428 (60)
Healthcare facility	623 (6)	456 (5)	171 (10)	441 (8)
Public location	660 (6)	599 (7)	64 (4)	961 (17)
Other	1,228 (12)	1,016 (12)	220 (13)	702 (12)
Missing/unknown	291 (3)	215 (3)	79 (5)	217 (4)
Response time in minutes, median (IQR)	6.6 (4.4, 8.7)	6.6 (4.4, 8.7)	6.6 (4.4, 8.7)	6.6 (4.4, 8.7)
Missing	48	37	11	83
Scene time in minutes, median (IQR)	13.1 (6.6, 17.5)	10.9 (6.6, 17.5)	13.1 (8.7, 17.5)	15.3 (10.9, 21.8)
Missing	668	476	198	1,244
Transport time in minutes, median (IQR)	13.1 (6.6, 21.8)	13.1 (8.7, 21.8)	13.1 (6.6, 19.7)	13.1 (8.7, 19.7)
Missing	921	649	282	1,398
Total prehospital time in minutes, median (IQR)	35.0 (26.2, 45.9)	35.0 (26.2, 45.9)	32.8 (26.2, 45.9)	37.1 (28.4, 50.2)
Missing	920	650	280	1,405

Abbreviations: IQR, interquartile range.

Table 2. Clinical characteristics of EMS activations.

	Maternal
	Overall (n = 10,243)	Out-of-hospital delivery (n = 8,614)	Delivery complications (n = 1,712)	Newborn Overall (n = 5,749)
Primary symptom, n (%)
Pregnancy, childbirth, puerperium	4,486 (47)	4,236 (53)	290 (18)	284 (7)
Symptoms and abnormal clinical/lab findings	2,850 (30)	1,960 (24)	914 (58)	2,147 (51)
Factors influencing health status	168 (2)	142 (1.8)	27 (1.7)	911 (22)
Disease of genitourinary system	725 (8)	413 (5)	321 (20)	16 (0.4)
Disease of nervous system	30 (0.3)	25 (0.3)	5 (0.3)	236 (6)
Diseases of circulatory system	10 (0.1)	7 (0.1)	3 (0.2)	173 (4)
Conditions originating in perinatal period	43 (0.4)	42 (1)	1 (0)	61 (1)
Diseases of respiratory system	4 (<0.1)	3 (0.04)	1 (0.1)	88 (2)
Unclassified by CCSR	1,178 (12)	1,178 (15)	6 (0)	51 (1)
Missing	682	608	144	1,530
Primary impression, n (%)
Pregnancy, childbirth, puerperium	8,401 (86)	6,998 (86)	1,479 (89)	974 (19)
Symptoms and abnormal clinical/lab findings	518 (5)	433 (5)	85 (5)	782 (16)
Factors influencing health status	45 (0.5)	38 (0.5)	7 (0.4)	875 (17)
Disease of genitourinary system	270 (3)	199 (2)	71 (4)	15 (0.3)
Disease of nervous system	45 (0.5)	39 (0.5)	6 (0.4)	226 (4)
Diseases of circulatory system	16 (0.2)	10 (0.1)	6 (0.4)	307 (6)
Conditions originating in perinatal period	281 (3)	275 (3)	7 (0.4)	1,016 (20)
Diseases of respiratory system	8 (0.1)	6 (0.1)	2 (0.1)	280 (6)
Unclassified by CCSR	143 (1)	143 (2)	2 (0.1)	9 (0.2)
Missing	455	472	47	710
Indication of alcohol/drug use, n (%)	215 (2)	193 (2)	26 (2)	229 (4)
Missing	2,628	2,101	544	2,009
Traumatic injury, n (%)	124 (1)	77 (1)	47 (3)	540 (10)
Missing	499	377	127	519
Procedures, n (%)
IV/IO access	4,424 (43)	3,791 (44)	690 (40)	610 (11)
IV fluids	50 (0.5)	47 (0.6)	5 (0.3)	3 (0.1)
Basic airway management	92 (1)	91 (1)	3 (0.2)	459 (8)
Advanced airway management	7 (0.1)	6 (0.1)	1 (0.1)	52 (1)
Field delivery	3,515 (34)	3,515 (41)	42 (2)	298 (5)
Cord clamping/cutting	20 (0.2)	20 (0.2)	0	4 (0.1)
Medications, n (%)
Oxygen	863 (8)	743 (9)	132 (8)	870 (15)
Epinephrine (0.1 mg/ml)	4 (0.04)	4 (0.1)	0	42 (0.7)
IV fluids	429 (4)	340 (4)	88 (5)	24 (0.4)
Magnesium sulfate	40 (0.4)	39 (0.5)	1 (0.1)	3 (0.1)
TXA	11 (0.1)	2 (0.02)	9 (0.5)	0
Oxytocin	41 (0.4)	23 (0.3)	20 (1)	0

Abbreviations: CCSR, Clinical Classification Software Revised; IO, intraosseous; IV, intravenous; TXA, tranexamic acid.

Table 3. Community characteristics of EMS activations.

	Maternal			Newborn
	Overall (n = 10,243)	Out-of-hospital delivery (n = 8,614)	Delivery complications (n = 1,712)	Overall (n = 5,749)
Urban area, n (%)	8,511 (87)	7,206 (87)	1,366 (83)	4,788 (87)
Missing	408	340	72	271
County in top quartile of social vulnerability, n (%)	2,977 (30)	2,701 (33)	293 (18)	1,565 (29)
Missing	421	348	77	274
County minority status & language SVI quartile, n (%)
Quartile 1 (lowest)	410 (4)	316 (4)	98 (6)	195 (4)
Quartile 2	770 (8)	617 (7)	165 (10)	397 (7)
Quartile 3	2,250 (23)	1912 (23)	367 (22)	1,066 (19)
Quartile 4 (highest)	6,392 (65)	5421 (66)	1,005 (61)	3,817 (70)
Missing	421	348	77	274
County in top quartile of % Black, n (%)	5,270 (54)	4,427 (54)	880 (54)	2,505 (46)
Missing	421	348	77	274
County in top quartile of preterm birth rate, n (%)	1,370 (14)	1,197 (15)	185 (11)	806 (15)
Missing	421	348	77	274
Presence of obstetric resources in county, n (%)	8,239 (84)	6,920 (84)	1,372 (84)	4,564 (83)
Missing	421	348	77	274

Abbreviations: SVI, Social Vulnerability Index.

Data Availability Statement

The dataset supporting the conclusions of this article is available from the National Emergency Medical Services Information System Technical Assistance Center (https://nemsis.org) through a data request process.