Maternal Parameters IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of IPI of P value
< 24 mon (n = 121) 24-59 mon (n = 583) 60-119 mon (n = 712) ≥120 mon (n = 246)
Maternal age at index conception (y) 30.75±3.5 31.43±3.31 33.88±3.2 37.14±2.95 < 0.001
≥ 35 16 (13.2) 86 (14.8) 284 (39.9) 195 (79.3) 0.001
< 35 105 (86.8) 497 (85.2) 428 (60.1) 51 (20.7)
Education (y) < 0.001
≤ 12 9 (7.4) 36 (6.2) 52 (7.4) 23 (9.4)
13-16 10 (8.3) 48 (8.3) 74 (10.5) 34 (13.9)
≥ 17 102 (84.3) 497 (85.5) 578 (82.1) 188 (76.7)
BMI, No. (Kg/m2) 0.005
< 18 19 (15.7) 74 (12.7) 55 (7.7) 14 (5.7)
18-23.9 80 (66.1) 395 (67.8) 525 (73.7) 173 (70.3)
24-27.9 22 (14.9) 93 (16) 116 (16.3) 51 (20.7)
> 28 4 (3.3) 21 (3.6) 16 (2.2) 8 (3.3)
Number of previous pregnancies < 0.001
≥ 3 66 (54.5) 366 (62.8) 530 (74.4) 218 (88.6)
< 3 55 (45.5) 217 (37.2) 182 (25.6) 28 (11.4)
Parity ≥ 2 16 (13.2) 38 (6.5) 26 (3.7) 10 (4.1) < 0.001
Prior cesareans ≥ 2 16 (13.2) 33 (5.7) 21 (2.9) 5 (2.0) 0.001
Prior vaginal birth 4 (3.3) 8 (1.4) 11 (1.5) 6 (2.4) 0.384
IVF-ET 2 (3.5) 6 (1.0) 4 (0.6) 3 (1.2) 0.007
Preexisting hypertension 2 (1.7) 2 (0.3) 4 (0.6) 4 (1.6) 0.128
Preexisting diabetes 0 (0) 3 (0.5) 2 (0.3) 2 (0.8) 0.60
Gestational age at delivery (weeks) 38.05±1.75 38.07± 1.81 38.12± 1.76 37.72± 2.21 0.027
Mode of delivery 0.178
Repeated cesarean section 117 (96.7) 560 (96.1) 696 (97.8) 242 (98.4)
Vaginal birth after CS 4 (3.3) 23 (3.9) 16 (2.2) 4 (1.6)
Type of repeated cesarean section
Emergency cesarean section 38 (32.2) 179 (31.9) 220 (31.6) 87 (36.0) 0.641
CS with indications 45 (37.2) 191 (34) 216 (31) 85 (35.1) 0.403