Table 2. Maternal and Fetal Adverse Outcomes by Severity of Anemia During Pregnancya.
| Outcome | Patients, No. (%) | ||||||
|---|---|---|---|---|---|---|---|
| No anemia (n = 15 578 790) | Anemia | Total (N = 18 948 443) | |||||
| Mild (n = 1 713 722) | Moderate (n = 497 363) | Severe (n = 40 458) | Unknown severity (n = 1 118 110) | All (n = 3 369 653) | |||
| Maternal | |||||||
| Placental abruption | 128 607 (0.83) | 19 862 (1.16) | 9275 (1.86) | 1496 (3.70) | 13 556 (1.21) | 44 189 (1.31) | 172 796 (0.91) |
| Preterm birth | 864 698 (5.55) | 118 470 (6.91) | 42 725 (8.59) | 4727 (11.68) | 73 610 (6.58) | 239 532 (7.11) | 1 104 230 (5.83) |
| Severe postpartum hemorrhage | 125 612 (0.81) | 21 704 (1.27) | 17 819 (3.58) | 4822 (11.92) | 25 392 (2.27) | 69 737 (2.07) | 195 349 (1.03) |
| Shock | 12 610 (0.08) | 1237 (0.07) | 1180 (0.24) | 1047 (2.59) | 1980 (0.18) | 5444 (0.16) | 18 054 (0.10) |
| Admission to ICU | 20 241 (0.13) | 1690 (0.10) | 948 (0.19) | 333 (0.82) | 2125 (0.19) | 5096 (0.15) | 25 337 (0.13) |
| Mortality, per 100 000 deliveries | 1357 (8.71) | 60 (3.50) | 28 (5.63) | 20 (49.43) | 132 (11.81) | 240 (7.12) | 1597 (8.43) |
| Cesarean delivery | 7 178 444 (46.08) | 855 105 (49.90) | 267 052 (53.69) | 20 218 (49.97) | 587 060 (52.50) | 1 729 435 (51.32) | 8 907 879 (47.01) |
| Fetal | |||||||
| Fetal growth restriction | 148 669 (0.95) | 16 792 (0.98) | 6052 (1.22) | 776 (1.92) | 11 890 (1.06) | 35 510 (1.05) | 184 179 (0.97) |
| Malformation | 184 895 (1.19) | 25 736 (1.50) | 9010 (1.81) | 954 (2.36) | 16 471 (1.47) | 52 171 (1.55) | 237 066 (1.25) |
| Stillbirth | 145 523 (0.93) | 9799 (0.57) | 4120 (0.83) | 1097 (2.71) | 7417 (0.66) | 22 433 (0.67) | 167 956 (0.89) |
Abbreviation: ICU, intensive care unit.
SI conversion factor: To convert hemoglobin concentration to grams per deciliter, divide by 10.0.
a
No anemia was defined as a hemoglobin concentration of 110 g/L or greater; mild anemia, 100 to 109 g/L; moderate anemia, 70 to 99 g/L; severe anemia, less than 70 g/L.