Table 1. Cohort Characteristics by LEA and Oxytocin Exposure.
| Characteristic | No. (%) | |||
|---|---|---|---|---|
| No LEA (n = 52 114) | LEA (n = 153 880) | No oxytocin (n = 88 186) | Oxytocin (n = 117 808) | |
| Maternal | ||||
| Age at delivery, median (IQR), y | 30.8 (26.8-34.5) | 30.0 (25.9-33.8) | 30.4 (26.5-34.1) | 30.0 (25.9-33.9) |
| Race and ethnicitya | ||||
| Asian or Pacific Islander | 6396 (12.3) | 21 532 (14.0) | 12 498 (14.2) | 15 430 (13.1) |
| Black | 3626 (6.9) | 11 099 (7.2) | 5945 (6.7) | 8780 (7.5) |
| Hispanic | 29 521 (56.6) | 76 961 (50.0) | 45 217 (51.3) | 61 265 (52.0) |
| White | 11 327 (21.7) | 40 061 (26.0) | 22 152 (25.1) | 29 236 (24.8) |
| Other | 1244 (2.4) | 4227 (2.7) | 2374 (2.7) | 3097 (2.6) |
| Educational level | ||||
| ≤High school | 17 414 (33.4) | 44 386 (28.8) | 26 590 (30.2) | 35 210 (29.9) |
| College and postgraduate | 18 669 (35.8) | 58 889 (38.3) | 34 235 (38.8) | 43 323 (36.8) |
| Some college | 15 260 (29.3) | 48 457 (31.5) | 26 028 (29.5) | 37 689 (32.0) |
| Unknown | 771 (1.5) | 2148 (1.4) | 1333 (1.5) | 1586 (1.3) |
| Household income, $ | ||||
| 0-29 999.99 | 766 (1.5) | 1708 (1.1) | 1116 (1.3) | 1358 (1.2) |
| 30 000-49 999.99 | 11 416 (21.9) | 27 200 (17.7) | 16 655 (18.9) | 21 961 (18.6) |
| 50 000-69 999.99 | 16 724 (32.1) | 46 565 (30.3) | 26 752 (30.3) | 36 537 (31.0) |
| 70 000-89 999.99 | 12 061 (23.1) | 38 347 (24.9) | 21 311 (24.2) | 29 097 (24.7) |
| ≥90 000 | 11 147 (21.4) | 40 060 (26.0) | 22 352 (25.3) | 28 855 (24.5) |
| Marital status | ||||
| Married or have partner | 28 739 (55.1) | 80 925 (52.6) | 46 417 (52.6) | 63 247 (53.7) |
| Not married | 8475 (16.3) | 27 550 (17.9) | 13 971 (15.8) | 22 054 (18.7) |
| Unknown | 14 900 (28.6) | 45 405 (29.5) | 27 798 (31.5) | 32 507 (27.6) |
| Parity | ||||
| 0 | 11 431 (21.9) | 53 285 (34.6) | 20 830 (23.6) | 43 886 (37.3) |
| 1 | 18 736 (36.0) | 48 088 (31.3) | 34 420 (39.0) | 32 404 (27.5) |
| ≥2 | 17 835 (34.2) | 31 301 (20.3) | 24 549 (27.8) | 24 587 (20.9) |
| Unknown | 4112 (7.9) | 21 206 (13.8) | 8387 (9.5) | 16 931 (14.4) |
| Prepregnancy BMI, median (IQR) | 25.1 (22.1-29.2) | 25.2 (22.2-29.6) | 24.6 (21.8-28.6) | 25.7 (22.5-30.2) |
| History of comorbidity | 7877 (15.1) | 27 582 (17.9) | 14 198 (16.1) | 21 261 (18.0) |
| Diabetes during pregnancy | ||||
| No diabetes | 46 912 (90.0) | 137 909 (89.6) | 80 584 (91.4) | 104 237 (88.5) |
| Gestational diabetes | 4179 (8.0) | 11 829 (7.7) | 6044 (6.9) | 9964 (8.5) |
| Preexisting diabetes | 1023 (2.0) | 4142 (2.7) | 1558 (1.8) | 3607 (3.1) |
| Hypertension/preeclampsia | ||||
| No hypertension | 48 990 (94.0) | 138 791 (90.2) | 84 007 (95.3) | 103 774 (88.1) |
| Gestational hypertension | 1046 (2.0) | 5255 (3.4) | 1580 (1.8) | 4721 (4.0) |
| Chronic hypertension | 787 (1.5) | 3168 (2.1) | 1168 (1.3) | 2787 (2.4) |
| Preeclampsia | 1291 (2.5) | 6666 (4.3) | 1431 (1.6) | 6526 (5.5) |
| Smoking during pregnancy | 241 (0.5) | 1171 (0.8) | 500 (0.6) | 912 (0.8) |
| Alcohol use | ||||
| No | 37 026 (71.0) | 101 801 (66.2) | 61 193 (69.4) | 77 634 (65.9) |
| Yes | 13 822 (26.5) | 48 171 (31.3) | 24 700 (28.0) | 37 293 (31.7) |
| Unknown | 1266 (2.4) | 3908 (2.5) | 2293 (2.6) | 2881 (2.4) |
| Drug use | ||||
| No | 38 320 (73.5) | 127 795 (83.0) | 68 924 (78.2) | 97 191 (82.5) |
| Yes | 68 (0.1) | 366 (0.2) | 158 (0.2) | 276 (0.2) |
| Unknown | 13 726 (26.3) | 25 719 (16.7) | 19 104 (21.7) | 20 341 (17.3) |
| Genitourinary infection during pregnancy | 13 059 (25.1) | 41 573 (27.0) | 22 061 (25.0) | 32 571 (27.6) |
| Seizures | 236 (0.5) | 803 (0.5) | 421 (0.5) | 618 (0.5) |
| Premature rupture of membrane | 3288 (6.3) | 12 154 (7.9) | 4311 (4.9) | 11 131 (9.4) |
| Hypothyroidism | 1553 (2.9) | 5039 (3.3) | 2718 (3.1) | 3874 (3.3) |
| Mental health issue | 4140 (7.9) | 17 059 (11.1) | 8254 (9.4) | 12 945 (11.0) |
| Induction | 8458 (16.2) | 52 463 (34.1) | 5341 (6.1) | 55 580 (47.2) |
| Augmentation | 16 790 (32.2) | 111 258 (72.3) | 10 240 (11.6) | 117 808 (100) |
| Labor dystocia | 740 (1.4) | 2531 (1.6) | 1113 (1.3) | 2158 (1.8) |
| Antepartum hemorrhage | 4470 (8.6) | 14 687 (9.5) | 7639 (8.7) | 11 518 (9.8) |
| Fever during labor | 656 (1.3) | 18 430 (12.0) | 3939 (4.5) | 15 147 (12.9) |
| Gestational weight gain, median (IQR), kg | 11.8 (8.2-15.0) | 12.4 (8.9-15.9) | 11.9 (8.6-15.5) | 12.4 (8.7-16.1) |
| Child characteristics | ||||
| Birth weight, median (IQR), g | 3330 (3030-3625) | 3355 (3060-3655) | 3336 (3050-3635) | 3357 (3050-3660) |
| Preterm | 3550 (6.8) | 8463 (5.5) | 5052 (5.7) | 6961 (5.9) |
| Birth defect | 4663 (8.9) | 15 120 (9.8) | 8336 (9.5) | 11 447 (9.7) |
| Sex | ||||
| Female | 25 984 (49.9) | 76 505 (49.7) | 43 826 (49.7) | 58 663 (49.8) |
| Male | 26 130 (50.1) | 77 375 (50.3) | 44 360 (50.3) | 59 145 (50.2) |
| Fetal distress | 7266 (13.9) | 37 477 (24.4) | 14 634 (16.6) | 30 109 (25.6) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); LEA, labor epidural analgesia.
a
Other race and ethnicity includes patients who self-identified as other or multiple races.