Developing and Validating Nomogram to Predict Severe Postpartum Hemorrhage in Women With Placenta Previa Undergoing Cesarean Delivery: A Multicenter Retrospective Case-Control Study

Interactions between ultrasonographic cervical length and placenta accreta spectrum on severe postpartum hemorrhage in women with placenta previa

OBJECTIVE

To explore the interactions between cervical length (CL) and placenta accreta spectrum (PAS) on severe postpartum hemorrhage (SPPH) in patients with placenta previa.

METHODS

A retrospective case-control study was conducted at four medical centers in China, and 588 patients with placenta previa were included. The logistic regression analysis and restricted cubic splines (RCS) were used to evaluate the association between CL and SPPH. Furthermore, the joint effect of CL and PAS on SPPH was assessed, and the additive and multiplicative interactions were calculated.

RESULTS

After adjusting for potential confounders, the negative linear dose-response relationship was confirmed by RCS, and the change of odds ratio (OR) was more significant when CL was 2.5 cm or less. The risk of SPPH was significantly higher when CL of 2.5 cm or less co-existed with placenta increta/percreta than when CL of 2.5 cm less, or placenta increta/percreta existed alone (adjusted OR [aOR]_{CL ≤2.5cm&placenta accreta/non-PAS} 3.40, 95% confidence interval [CI] 1.37-8.45; aOR_{placenta increta/percreta&CL >2.5cm} 4.75, 95% CI 3.03-7.47; aOR_{CL ≤2.5cm&placenta increta/percreta} 14.51, 95% CI 6.08-34.64), and there might be additive interaction between CL and placenta increta/percreta on SPPH (attributable proportion due to interaction 50.7%, 95% CI 6.1%-95.3%).

CONCLUSION

If CL was routinely performed during PAS evaluation, the increased OR of short CL and PAS could allow better patient preparation through counseling.

Association of the placenta accreta spectrum score and estimated blood loss in placenta accreta spectrum patients with placenta previa: a retrospective cohort study

PURPOSE

The placenta accreta spectrum (PAS) score calculated by the scoring system may predict patients with PAS. We aim to find the relationship between estimated blood loss and the PAS score. Further, find the inflection point, identify PAS patients with placenta previa who were at risk for major bleeding.

METHODS

The PAS patients with placenta previa, as diagnosed by color Doppler ultrasound, were divided into two groups according to their PAS scores using a new scoring system. Blood loss, transfusion requirements, the rate of Intra-Abdominal Balloon Occlusion (IABO), and other indicators were analyzed between groups.

RESULTS

The estimated blood loss, intraoperative transfusion, postoperative transfusion, operation time, and hospitalization time significantly increased in the group with a PAS score ≥ 9 (P < 0.05). The inflection point analysis revealed that a significant increase in estimated blood loss occurred when the PAS score was beyond 10 (crude) or 6 (adjusted for age, body mass index, and IABO).

CONCLUSION

There was a non-linear relationship between estimated intraoperative blood loss and PAS score. When the PAS score was greater than 9, hemorrhage, the risk of major bleeding, the need for transfusions, and the placement of an abdominal aortic balloon all increase significantly.

Association of Placenta Previa With Severe Maternal Morbidity Among Patients With Placenta Accreta Spectrum Disorder

IMPORTANCE

Placenta previa is widely acknowledged as a risk factor for placenta accreta spectrum (PAS) disorders, which are severe maternal complications; however, data are limited regarding whether placenta previa is associated with a higher risk of worse maternal outcomes among patients with PAS disorders.

OBJECTIVE

To examine the association between placenta previa and the risk of severe maternal morbidities (SMMs) and higher resource use among patients with PAS disorders.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study extracted records of 3793 patients with PAS diagnosis and delivery indicators between October 1, 2015, and December 31, 2019, from the US National Inpatient Sample database.

EXPOSURES

Placenta previa.

MAIN OUTCOMES AND MEASURES

Data on 21 Centers for Disease Control and Prevention-defined SMMs and 25 study-defined surgical morbidities associated with PAS were extracted. Six surgical procedures (cystoscopy, intra-arterial balloon occlusion, cesarean delivery, hysterectomy, cystectomy, and oophorectomy), hospital length of stay, and inpatient costs were compared. Multivariable Poisson regression models built in the generalized estimating equation framework were used.

RESULTS

Among 3793 patients with PAS (median [IQR] age at admission, 33 [29-37] years), 621 women (16.4%) were Black, 765 (20.2%) were Hispanic, 1779 (46.9%) were White, 441 (11.6%) were of other races and/or ethnicities (47 [1.2%] were American Indian, 220 [5.8%] were Asian or Pacific Islander, and 174 [4.6%] were of multiple or other races and/or ethnicities), and 187 (4.9%) were of unknown race and ethnicity. A total of 1323 patients (34.9%) had placenta previa and 2470 patients (65.1%) did not; of those with placenta previa, 405 patients (30.6%) had invasive PAS. Patients with vs without placenta previa had a significantly higher rate and risk of any SMM (935 women [70.7%] vs 1087 women [44.0%]; P < .001; adjusted risk ratio [aRR], 1.19; 95% CI, 1.12-1.27) and any surgical morbidity (1170 women [88.4%] vs 1667 women [67.5%]; P < .001; aRR, 1.18; 95% CI, 1.13-1.23). With regard to specific outcomes, those with vs without placenta previa had a significantly higher rate of peripartum hemorrhage (878 patients [66.4%] vs 1217 patients [49.3%]; P < .001), blood product transfusion (413 patients [31.2%] vs 610 patients [24.7%]; P < .001), shock (83 patients [6.3%] vs 108 patients [4.4%]; P = .01), disseminated intravascular coagulation or other coagulopathy (77 patients [5.8%] vs 105 patients [4.3%]; P = .04), and urinary tract injury (44 patients [3.3%] vs 41 patients [1.7%]; P = .002). Patients with vs without placenta previa were more likely to undergo cesarean delivery (1292 patients [97.7%] vs 1787 patients [72.3%]; P < .001), hysterectomy (786 patients [59.4%] vs 689 patients [27.9%]; P < .001), cystoscopy (301 patients [22.8%] vs 203 patients [8.2%]; P < .001), cystectomy (157 patients [11.9%] vs 98 patients [4.0%]; P < .001), and intra-arterial balloon occlusion (121 patients [9.1%] vs 77 patients [3.1%]; P < .001) and to have significantly longer hospital length of stay (median [IQR], 5 [4-11] days vs 3 [3-5] days; P < .001) and total inpatient costs (median [IQR], $17 496 [$10 863-$30 619] vs $9728 [$6130-$16 790]; P < .001). Hypertensive disorder of pregnancy was associated with a decreased risk of placenta previa (aRR, 0.67; 95% CI, 0.46-0.96) among patients with PAS.

CONCLUSIONS AND RELEVANCE

In this study, placenta previa was associated with an increased risk of maternal and surgical morbidities and higher resource use among women with PAS. These findings suggest that interventions to alleviate maternal and surgical morbidities are especially needed for patients with placenta previa-complicated PAS disorders.