Table II.
Characteristics of the study population
| Characteristic | Pregnant inpatients | |
|---|---|---|
| Total patients, No. | 6,356,046 | |
| Age in years | Median [Q1–Q3] | |
| 28 [27.45–31] | ||
| Age groups | No. | % |
| 10–14 | 1,181 | 0.02 |
| 15–19 | 134,824 | 2.12 |
| 20–24 | 711,686 | 11.20 |
| 25–29 | 1,761,944 | 27.72 |
| 30–34 | 2,245,568 | 35.33 |
| 35–39 | 1,230,025 | 19.35 |
| 40–44 | 255,547 | 4.02 |
| 45–49 | 13,163 | 0.21 |
| 50–54 | 840 | 0.01 |
| 55–59 | 96 | <0.01 |
| 60–64 | 4 | <0.01 |
| Birth mode | No. | % |
| Vaginal delivery | 4,313,530 | 67.86 |
| Cesarean section | 2,247,528 | 35.36 |
| Risk factors | No. | % |
| Essential hypertension | 10,428 | 0.16 |
| Gestational hypertension | 72,920 | 1.15 |
| Diabetes during pregnancy (pre-existing) | 374,418 | 5.90 |
| Gestational diabetes | 346,601 | 5.45 |
| Nicotine abuse | 34,050 | 0.54 |
| Obesity | 151,959 | 2.40 |
| Grade I | 25,743 | 0.41 |
| Grade II | 22,245 | 0.35 |
| Grade III | 25,405 | 0.40 |
| Vitamin B12-, folic acid-, any other dietary anemia | 1,500 | 0.02 |
| Anemia of unspecified cause | 752,965 | 11.85 |
| Anemia due to acute bleeding situations | 660,144 | 10.39 |
| Anemia during pregnancy | 1,508,664 | 23.74 |
| Anticoagulation therapy | 8,780 | 0.14 |
| Bleeding | No. | % |
| Prepartum hemorrhage | 24,759 | 0.39 |
| Prepartum hemorrhage due to coagulation disorder | 418 | <0.01 |
| Intrapartum hemorrhage | 26,510 | 0.40 |
| Postpartum hemorrhage | 305,610 | 4.80 |
| Transfusion groups | No. | % |
| No RBC transfusion | 6,277,789 | 98.77 |
| RBC transfusion | 78,257 | 1.23 |
| ICU admission | 30,540 | 0.48 |
Q1–Q3: interquartile range; RBC: red blood cell; ICU: intensive care unit.