Table 4.
Number of Cases of Severe Maternal Morbidity and Number of Subsequent Pregnancies According to Interpregnancy Interval, by Parity or Maternal Age at the Index Pregnancy, Among Women Who Gave Birth at Least Twice in California Between 1997 and 2012
|
Parity or Maternal Age
at Index Pregnancy and IPI, months |
Overall SMM | SMM Minus Transfusion-Only Cases | ||||
|---|---|---|---|---|---|---|
|
No. of
SMM Cases |
No. of
Subsequent Pregnancies |
% With
SMM |
No. of
SMM Cases |
No. of
Subsequent Pregnancies |
% With
SMM |
|
| Parity 1 | ||||||
| <6 | 550 | 67,561 | 0.81 | 219 | 67,230 | 0.33 |
| 6–11 | 1,231 | 160,854 | 0.77 | 571 | 160,194 | 0.36 |
| 12–17 | 1,524 | 202,612 | 0.75 | 725 | 201,813 | 0.36 |
| 18–23 | 1,409 | 174,711 | 0.81 | 700 | 174,002 | 0.40 |
| 24–59 | 4,336 | 456,950 | 0.95 | 2,256 | 454,870 | 0.50 |
| ≥60 | 1,845 | 140,838 | 1.31 | 976 | 139,969 | 0.70 |
| Parity 2 | ||||||
| <6 | 486 | 40,305 | 1.21 | 196 | 40,015 | 0.49 |
| 6–11 | 741 | 76,506 | 0.97 | 371 | 76,136 | 0.49 |
| 12–17 | 766 | 83,083 | 0.92 | 365 | 82,682 | 0.44 |
| 18–23 | 716 | 70,337 | 1.02 | 342 | 69,963 | 0.49 |
| 24–59 | 2,549 | 221,708 | 1.15 | 1,317 | 220,476 | 0.60 |
| ≥60 | 1,407 | 91,587 | 1.54 | 730 | 90,910 | 0.80 |
| Parity 3 | ||||||
| <6 | 326 | 21,394 | 1.52 | 122 | 21,190 | 0.58 |
| 6–11 | 481 | 36,621 | 1.31 | 239 | 36,379 | 0.66 |
| 12–17 | 472 | 37,283 | 1.27 | 216 | 37,027 | 0.58 |
| 18–23 | 403 | 29,375 | 1.37 | 201 | 29,173 | 0.69 |
| 24–59 | 1,287 | 87,169 | 1.48 | 667 | 86,549 | 0.77 |
| ≥60 | 728 | 35,727 | 2.04 | 394 | 35,393 | 1.11 |
| Maternal age <20 years | ||||||
| <6 | 280 | 25,997 | 1.08 | 78 | 25,795 | 0.30 |
| 6–11 | 356 | 37,960 | 0.94 | 111 | 37,715 | 0.29 |
| 12–17 | 354 | 38,250 | 0.93 | 121 | 38,017 | 0.32 |
| 18–23 | 309 | 32,589 | 0.95 | 116 | 32,396 | 0.36 |
| 24–59 | 1,142 | 116,924 | 0.98 | 464 | 116,246 | 0.40 |
| ≥60 | 682 | 58,099 | 1.17 | 334 | 57,751 | 0.58 |
| Maternal age 20–34 years | ||||||
| <6 | 1,376 | 111,613 | 1.23 | 539 | 110,776 | 0.49 |
| 6–11 | 2,270 | 232,920 | 0.97 | 1,059 | 231,709 | 0.46 |
| 12–17 | 2,440 | 273,354 | 0.89 | 1,147 | 272,061 | 0.42 |
| 18–23 | 2,238 | 232,718 | 0.96 | 1,091 | 231,571 | 0.47 |
| 24–59 | 7,297 | 645,916 | 1.13 | 3,829 | 642,448 | 0.60 |
| ≥60 | 3,669 | 223,049 | 1.64 | 1,955 | 221,335 | 0.88 |
| Maternal age ≥35 years | ||||||
| <6 | 166 | 10,950 | 1.52 | 78 | 10,862 | 0.72 |
| 6–11 | 442 | 32,015 | 1.38 | 251 | 31,824 | 0.79 |
| 12–17 | 496 | 38,037 | 1.3 | 267 | 37,808 | 0.71 |
| 18–23 | 395 | 29,389 | 1.34 | 227 | 29,221 | 0.78 |
| 24–59 | 998 | 57,406 | 1.74 | 569 | 56,977 | 1.00 |
| ≥60 | 161 | 6,331 | 2.54 | 78 | 6,248 | 1.25 |
Abbreviations: IPI, interpregnancy interval; SMM, severe maternal morbidity.