Table 2.
Maternal cardiovascular and non-cardiovascular mortality, age 40 to 69 years, by number of births stratified by education.
| CARDIOVASCULAR CAUSES *
| |||||
|---|---|---|---|---|---|
| EDUCATION | NUMBER OF BIRTHS | NUMBER OF MOTHERS | MATERNAL DEATHS (PER 1000) | HR (95% CI) †
|
HR (95% CI) †
|
| ref.: mothers with 2 births | ref.: mothers with 2 births and 11+ years of education | ||||
| LOW (<11 YEARS) | 1 | 45190 | 429 (9.5) | 1.7 (1.5–1.9) | 4.0 (3.3–4.8) |
| 2 | 132112 | 617 (4.7) | 1.0 (ref.) | 2.4 (2.0–2.8) | |
| 3 | 76766 | 340 (4.4) | 1.1 (0.94–1.2) | 2.6 (2.1–3.1) | |
| 4 | 22347 | 102 (4.6) | 1.2 (0.96–1.5) | 2.8 (2.2–3.6) | |
| ≥5 | 7497 | 35 (4.7) | 1.3 (0.94–1.9) | 3.1 (2.2–4.5) | |
| p-trend=0.02 ‡ | |||||
|
| |||||
| TOTAL | 283 912 | 1523 (5.4) | 2.6 (2.3–2.9) | ||
|
| |||||
| HIGH (≥11 YEARS) | 1 | 31419 | 111 (3.5) | 1.8 (1.4–2.3) | 1.9 (1.5–2.4) |
| 2 | 111698 | 181 (1.6) | 1.0 (ref.) | 1.0 (ref.) | |
| 3 | 74397 | 77 (1.0) | 0.78 (0.60–1.02) | 0.77 (0.59–1.01) | |
| 4 | 19513 | 17 (0.9) | 0.70 (0.42–1.2) | 0.69 (0.42–1.1) | |
| ≥5 | 5375 | 5 (0.9) | 0.74 (0.30–1.8) | 0.73 (0.30–1.8) | |
| p-trend=0.045 ‡ | |||||
|
| |||||
| TOTAL | 242 402 | 391 (1.6) | 1.0 (ref.) | ||
|
| |||||
| NON-CARDIOVASCULAR CAUSES * | |||||
|
| |||||
| LOW (<11 YEARS) | 1 | 44 761 | 2 533 (56.6) | 1.4 (1.4–1.5) | 2.3 (2.2–2.4) |
| 2 | 131 495 | 4 678 (35.6) | 1.0 (ref.) | 1.6 (1.5–1.7) | |
| 3 | 76 426 | 2 308 (30.2) | 0.94 (0.90–0.99) | 1.5 (1.4–1.6) | |
| 4 | 22 245 | 646 (29.0) | 0.96 (0.89–1.1) | 1.6 (1.4–1.7) | |
| ≥5 | 7 462 | 199 (26.7) | 0.95 (0.83–1.1) | 1.6 (1.3–1.8) | |
| p-trend=0.11 ‡ | |||||
|
| |||||
| TOTAL | 282 389 | 10 364 (36.7) | 1.7 (1.6–1.7) | ||
|
| |||||
| HIGH (≥11 YEARS) | 1 | 31 308 | 903 (28.4) | 1.4 (1.3–1.5) | 1.4 (1.3–1.5) |
| 2 | 111 517 | 2 075 (18.6) | 1.0 (ref.) | 1.0 (ref.) | |
| 3 | 74 320 | 1 026 (13.8) | 0.89 (0.83–0.96) | 0.88 (0.81–0.94) | |
| 4 | 19 496 | 255 (13.1) | 0.90 (0.79–1.02) | 0.88 (0.77–1.00) | |
| ≥5 | 5 370 | 60 (11.2) | 0.76 (0.59–0.98) | 0.75 (0.58–0.96) | |
| p-trend<0.01 ‡ | |||||
|
| |||||
| TOTAL | 242 011 | 4 319 (17.8) | 1.0 (ref.) | ||
*
Data are defined; Cardiovascular causes of death: Ischemic heart diseases and cerebrovascular disease combined. Non-cardiovascular causes of death: All other causes than cardiovascular causes (see material and method).
†
Data are presented with ratios; HR=Hazard Ratio with 95% confidence interval, adjusted for mother’s birth year.
‡
Data are assessed for linearity; P-trend: linear association between maternal mortality and increasing number of births exceeding one.