Table 3.
Association between the quality of pregnancy dating retrieved at birth and obstetric interventions in labor.
| Obstetric intervention during labor |
PDa with USb <14 weeks (N=1163), n (%) |
PD with US<20 weeks (N=1456), n (%) |
Suboptimal PDc (N=657), n (%) |
<14 weeks vs suboptimal dating, ORd (95% CI) |
P valuee | <20 weeks vs suboptimal dating, OR (95% CI) |
P valuee |
| Nonspontaneous vaginal delivery | 652 (56.06) | 803 (55.15) | 288 (43.84) | 1.64 (1.35-1.98) | <.001 | 1.58 (1.31-1.90) | <.001 |
| Oxytocin augmentation | 230 (19.77) | 277 (19.03) | 98657 (14.92) | 1.41 (1.09-1.82) | .01 | 1.34 (1.04-1.72) | .02 |
| Cesarean section | 475 (40.83) | 584 (40.11) | 244 (37.14) | 1.17 (0.96-1.42) | .12 | 1.13 (0.94-1.37) | .20 |
| Vaginal birth with forceps |
42 (3.61) | 46 (3.16) | 17 (2.59) | 0.71 (0.40-1.26) | .24 | 1.23 (0.69-2.16) | .47 |
aPD: pregnancy dating.
bUS: ultrasound.
cUltrasound done ≥20 weeks of gestation or not done at all.
dOR: odds ratio.
eChi-square test.