Table 2 Obstetric and labor related characteristics of patients with and without obstetric anal sphincter injury (OASI) according to age groups
≤21 years | 26–35 years | |||||
|---|---|---|---|---|---|---|
Parameter | OASI | No OASI | P valuea | OASI | No OASI | P valuea |
No. of patients | 67 (1.3%) | 5046 (98.7%) | 199 (1.7%) | 13,646(98.3%) | ||
Age | 20.2 ± 1.0 (21.0) | 20.3 ± 1.0 (20.6) | 0.780 | 28.8 ± 2.3 (28.0) | 29.2 ± 1.2 (29.0) | 0.008 |
Gestational diabetes | 0 | 32 (0.6%) | 1.000 | 6 (3.0%) | 263 (1.9%) | 0.289 |
PIH/Preeclampsia | 2 (3.0%) | 5/4342 (1.2%) | 0.198 | 0 | 107/11662 (1.2%) | 0.430 |
Gestational week | 39.8 ± 1.1 (40) | 39.6 ± 1.2 (40) | 0.079 | 39.7 ± 1.2 (40) | 39.7 ± 1.1 (40) | 0.007 |
Induction of labor | 15 (22.4%) | 769 (15.3%) | 0.082 | 59 (29.6%) | 3089 (22.7%) | 0.025 |
Epidural analgesia | 46 (69.7%) | 3258 (64.5%) | 0.438 | 151 (76.3%) | 10,358 (75.9%%) | 0.994 |
Artificial rupture of membranes | 29/58 (50.0%) | 2190/4042(54.2%) | 0.596 | 85/172 (49.4%) | 5319/11,074(48.0%) | 0.759 |
Meconium stained amniotic fluid | 6 (9.1%) | 758/4860 (15.6%) | 0.172 | 42 (21.3%) | 2496 (18.9%) | 0.412 |
Prolonged 2nd stage | 14 (20.9%) | 714/4947 (14.4%) | 0.160 | 50 (25.8%) | 2847 (21.3%) | 0.132 |
Operative vaginal delivery | 14 (20.9%) | 769 (15.2%) | 0.229 | 72 (36.2%) | 3044 (22.3%) | < 0.001 |
Birth weight (grams) | 3385 ± 421 (3406) | 3321 ± 397 (3214) | 0.001 | 3382 ± 413 (3386) | 3205 ± 395(3190) | < 0.001 |
Birth weight > 90th percentile (> 3900 g) | 5 (7.5%) | 240 (4.7%) | 0.252 | 19 (9.5%) | 603 (4.4%) | 0.003 |
Head circumference (cm)b | 34.5 ± 1.4 (34.3) | 34.2 ± 1.2 (34.0) | 0.047 | 34.6 ± 1.2 (34.5) | 34.3 ± 1.2 (34.3) | 0.007 |
Head circumference > 90th percentile (> 36 cm)b | 12/51 (24.1%) | 210/2317 (9.1%) | 0.002 | 23/139 (16.5%) | 733/7138 (10.3%) | 0.024 |
Episiotomy | 18 (26.9%) | 1245/4340(28.7%) | 0.892 | 67 (33.7%) | 2908 (24.9%) | 0.006 |