Maternal demographic and clinical characteristics among pregnancies with and without fetal reduction
| Characteristic | Fetal reduction; no. (%) of pregnancies | No fetal reduction; no. (%) of pregnancies | |||
|---|---|---|---|---|---|
| Reduced to twin pregnancy n = 45 | Reduced to singleton pregnancy n = 50 | Triplet pregnancy n = 40 | Twin pregnancy n = 3340 | Singleton pregnancy n = 203 833 | |
| Maternal age at delivery, yr | |||||
| < 35 | 17 (37.8) | 17 (34.0) | 23 (57.5) | 2123 (63.6) | 156 660 (76.9) |
| 35–39 | 20 (44.4) | 17 (34.0) | > 13* (> 30.0) | 898 (26.9) | 38 240 (18.8) |
| ≥ 40 | 8 (17.8) | 16 (32.0) | < 5* (< 12.5) | 319 (9.6) | 8933 (4.4) |
| Parity | |||||
| Nulliparous | 30 (66.7) | 23 (46.0) | 26 (65.0) | 1729 (51.8) | 94 879 (46.6) |
| Multiparous | 15 (33.3) | 27 (54.0) | 14 (35.0) | 1611 (48.2) | 108 954 (53.5) |
| Pre-pregnancy weight, kg | n = 38 | n = 42 | n = 35 | n = 2579 | n = 164 757 |
| < 60 | 14 (36.8) | 14 (33.3) | 8 (22.9) | 891 (34.5) | 66 216 (40.2) |
| 60–69 | 8 (21.1) | 12 (28.6) | 11 (31.4) | 780 (30.2) | 47 195 (28.6) |
| 70–79 | 8 (21.1) | 8 (19.0) | 10 (28.6) | 430 (16.7) | 25 983 (15.8) |
| ≥ 80 | 8 (21.1) | 8 (19.0) | 6 (17.1) | 478 (18.5) | 25 363 (15.4) |
| Socioeconomic status | n = 44 | n = 48 | n = 3293 | n = 200 729 | |
| Lowest | 18 (40.9) | 11 (22.9) | 15 (37.5) | 1264 (38.4) | 85 478 (42.6) |
| Middle | 16 (36.4) | 20 (41.7) | 14 (35.0) | 1411 (42.8) | 82 802 (41.3) |
| Highest | 10 (22.7) | 17 (35.4) | 11 (27.5) | 618 (18.8) | 32 449 (16.2) |
| Gestational diabetes | |||||
| No | 32 (71.1) | 42 (84.0) | 32 (80.0) | 2882 (86.3) | 183 667 (90.1) |
| Yes | 13 (28.9) | 8 (16.0) | 8 (20.0) | 458 (13.7) | 20 166 (9.9) |
| Hypertension in pregnancy | |||||
| No | 39 (86.7) | 50 (100.0) | > 35* (> 87.5) | 3119 (93.4) | 199 378 (97.8) |
| Yes | 6 (13.3) | 0 (0.0) | < 5* (< 12.5) | 221 (6.6) | 4455 (2.2) |
| Mode of delivery | n = 3329 | ||||
| Cesarean | 31 (68.9) | 21 (42.0) | > 35* (> 87.5) | 2341 (70.2) | 61 933 (30.4) |
| Vaginal | 14 (31.1) | 29 (58.0) | < 5* (< 12.5) | 988 (29.8) | 141 900 (69.6) |
| Use of assisted reproductive technology | |||||
| No | < 5* (< 11.1) | 18 (36.0) | 14 (35.0) | 2153 (64.5) | 198 195 (97.2) |
| Yes | > 40* (> 88.9) | 32 (64.0) | 26 (65.0) | 1187 (35.5) | 5638 (2.8) |
↵* Exact count suppressed for confidentiality reasons as a result of small numbers in this or related cells.