Characteristics of mothers and their daughters born between 1992 and 1999, according to whether the mother had an induced abortion between 4 years before and 12 years after the daughter’s birth date
| Characteristic | Maternal induced abortion; no. (%) of daughters* | Standardized difference | |
|---|---|---|---|
| Yes n = 73 518 | No n = 358 105 | ||
| Mother’s age at daughter’s birth, yr | |||
| Mean ± SD | 26.2 ± 5.7 | 29.5 ± 5.1 | −0.61 |
| < 20 | 10 012 (13.6) | 11 214 (3.1) | 0.39 |
| 20–24 | 19 721 (26.8) | 47 094 (13.2) | 0.35 |
| 25–29 | 22 187 (30.2) | 117 144 (32.7) | −0.05 |
| 30–34 | 15 834 (21.5) | 125 415 (35.0) | −0.3 |
| 35–39 | 5197 (7.1) | 49 789 (13.9) | −0.22 |
| ≥ 40 | 567 (0.8) | 7449 (2.1) | −0.11 |
| Mother’s world region of origin | |||
| Africa | 1533 (2.1) | 4014 (1.1) | 0.08 |
| Canada | 54 930 (74.7) | 314 130 (87.7) | −0.34 |
| Caribbean | 2588 (3.5) | 3217 (0.9) | 0.18 |
| East Asia | 4029 (5.5) | 10 256 (2.9) | 0.13 |
| Hispanic America | 1879 (2.6) | 4170 (1.2) | 0.1 |
| Middle East | 885 (1.2) | 3734 (1.0) | 0.02 |
| South Asia | 5761 (7.8) | 8327 (2.3) | 0.25 |
| Western nation other than Canada | 1913 (2.6) | 10 257 (2.9) | −0.02 |
| Daughter’s year of birth | |||
| 1992 | 5081 (6.9) | 33 495 (9.4) | −0.09 |
| 1993 | 8547 (11.6) | 47 788 (13.3) | −0.05 |
| 1994 | 9976 (13.6) | 49 222 (13.7) | −0.01 |
| 1995 | 10 420 (14.2) | 47 728 (13.3) | 0.02 |
| 1996 | 9858 (13.4) | 46 047 (12.8) | 0.02 |
| 1997 | 9877 (13.4) | 45 205 (12.6) | 0.02 |
| 1998 | 10 074 (13.7) | 44 907 (12.5) | 0.03 |
| 1999 | 9685 (13.2) | 43 713 (12.2) | 0.03 |
| Daughter born preterm (< 37 wk gestational age) | 4988 (6.8) | 22 188 (6.2) | 0.02 |
| Residential income quintile of daughter at birth | |||
| Q1 (lowest) | 25 327 (34.4) | 74 488 (20.8) | 0.31 |
| Q2 | 17 240 (23.4) | 72 364 (20.2) | 0.08 |
| Q3 | 13 017 (17.7) | 73 403 (20.5) | −0.07 |
| Q4 | 10 523 (14.3) | 75 372 (21.0) | −0.18 |
| Q5 (highest) | 7411 (10.1) | 62 478 (17.4) | −0.22 |
| Rural residence of daughter at birth | 5207 (7.1) | 47 679 (13.3) | 0.21 |
| Daughter had mental illness in 2 yr before turning age 12 yr† | 8446 (11.5) | 38 398 (10.7) | 0.02 |
| Daughter had major physical illness in 2 yr before turning age 12 yr† | 12 506 (17.0) | 64 178 (17.9) | −0.02 |
| Mother–daughter cohabitation when daughter turned age 12 yr | 46 394 (63.1) | 232 463 (64.9) | 0.04 |
| Residential income quintile of daughter at age 12 yr | |||
| Q1 (lowest) | 18 454 (25.1) | 54 197 (15.1) | 0.25 |
| Q2 | 16 743 (22.8) | 63 341 (17.7) | 0.13 |
| Q3 | 15 104 (20.5) | 72 651 (20.3) | 0.01 |
| Q4 | 13 007 (17.7) | 81 371 (22.7) | 0.13 |
| Q5 (highest) | 10 210 (13.9) | 86 545 (24.2) | −0.26 |
| Rural residence of daughter at age 12 yr | 5510 (7.5) | 45 442 (12.7) | 0.17 |
| Induced abortion rate in dissemination area where the daughter was residing at age 12 yr, per 1000 | |||
| 0 | 42 385 (57.7) | 239 340 (66.8) | −0.19 |
| 0.1–9.9 | 5651 (7.7) | 18 508 (5.2) | 0.10 |
| 10.0–19.9 | 9209 (12.5) | 32 396 (9.0) | 0.11 |
| 20.0–29.9 | 6659 (9.1) | 27 823 (7.8) | 0.05 |
| 30.0–39.9 | 4095 (5.6) | 17 637 (4.9) | 0.03 |
| ≥ 40 | 5519 (7.5) | 22 401 (6.3) | 0.05 |
| Study follow-up for daughter, from birth to primary end point, yr, mean ± SD‡ | 18.5 ± 1.6 | 18.7 ± 1.5 | 0.11 |
Note: SD = standard deviation.
↵* Except where indicated otherwise.
↵† Based on Johns Hopkins Adjusted Aggregated Diagnosis Groups.
↵‡ End of follow-up was defined as the earliest of the following: date of first induced abortion, date of death, date lost to follow-up from administrative data sets, 20th birthday or Mar. 31, 2016.