Value of first‐trimester ultrasound in prediction of third‐trimester sonographic stage of placenta accreta spectrum disorder and surgical outcome

Abstract

Objectives To explore whether early first‐trimester ultrasound can predict the third‐trimester sonographic stage of placenta accreta spectrum (PAS) disorder and to elucidate whether combining first‐trimester ultrasound findings with the sonographic stage of PAS disorder can stratify the risk of adverse surgical outcome in women at risk for PAS disorder. Methods This was a retrospective analysis of prospectively collected data from women with placenta previa, and at least one previous Cesarean delivery (CD) or uterine surgery, for whom early first‐trimester (5–7 weeks' gestation) ultrasound images could be retrieved. The relationship between the position of the gestational sac and the prior CD scar was assessed using three sonographic markers for first‐trimester assessment of Cesarean scar (CS) pregnancy, reported by Calí et al. (crossover sign (COS)), Kaelin Agten et al. (implantation of the gestational sac on the scar vs in the niche of the CS) and Timor‐Tritsch et al. (position of the center of the gestational sac below vs above the midline of the uterus), by two different examiners blinded to the final diagnosis and clinical outcome. The primary aim of the study was to explore the association between first‐trimester ultrasound findings and the stage of PAS disorder on third‐trimester ultrasound. Our secondary aim was to elucidate whether the combination of first‐trimester ultrasound findings and sonographic stage of PAS disorder can predict surgical outcome. Logistic regression analysis and area under the receiver‐operating‐characteristics curve (AUC) were used to analyze the data. Results One hundred and eighty‐seven women with vasa previa were included. In this cohort, 79.6% (95% CI, 67.1–88.2%) of women classified as COS‐1, 94.4% (95% CI, 84.9–98.1%) of those with gestational‐sac implantation in the niche of the prior CS and 100% (95% CI, 93.4–100%) of those with gestational sac located below the uterine midline, on first‐trimester ultrasound, were affected by the severest form of PAS disorder (PAS3) on third‐trimester ultrasound. On multivariate logistic regression analysis, COS‐1 (odds ratio (OR), 7.9 (95% CI, 4.0–15.5); P < 0.001), implantation of the gestational sac in the niche (OR, 29.1 (95% CI, 8.1–104); P < 0.001) and location of the gestational sac below the midline of the uterus (OR, 38.1 (95% CI, 12.0–121); P < 0.001) were associated independently with PAS3, whereas parity (P = 0.4) and the number of prior CDs (P = 0.5) were not. When translating these figures into diagnostic models, first‐trimester diagnosis of COS‐1 (AUC, 0.94 (95% CI, 0.91–0.97)), pregnancy implantation in the niche (AUC, 0.92 (95% CI, 0.89–0.96)) and gestational sac below the uterine midline (AUC, 0.92 (95% CI, 0.88–0.96)) had a high predictive accuracy for PAS3. There was an adverse surgical outcome in 22/187 pregnancies and it was more common in women with, compared to those without, COS‐1 (P < 0.001), gestational‐sac implantation in the niche (P < 0.001) and gestational‐sac position below the uterine midline (P <...

Reproductive outcome after cesarean scar pregnancy: A systematic review and meta‐analysis

“…Surgical treatment of CSP may affect the integrity of the anterior uterine wall and may sometimes end up in unplanned hysterectomy, especially in those cases presenting with severe life‐threatening symptoms, thus affecting the future fertility of these women. Conversely, non‐surgical treatment may lead to the incomplete removal of the CSP and the persistence of the cesarean scar, thus predisposing to a recurrent CSP 1‐5 . In the present systematic review, CSP recurred in 17% of women with a prior CSP, thus highlighting the need for an early ultrasound assessment during the first trimester of pregnancy to rule out CSP.…”

“…Women with CSP are at increased risk of uterine rupture and PAS, due to the anatomical weakness of the myometrium and the presence of a prior scar. This may partially explain the high incidence of uterine rupture and PAS observed in pregnancies affected by a prior CSP and highlights the need for a thorough follow up throughout pregnancy to detect these anomalies in time 1‐5 …”

“…CSP refers to the implantation of the gestational sac in the area of the prior cesarean section (CS) scar, which may lead to severe hemorrhage, uterine rupture and hysterectomy. More recently, CSP has been linked with the occurrence of placenta accreta spectrum (PAS) disorders 1‐6 …”

Cesarean Scar Pregnancy Successfully Managed to Term: When the Patient Is Determined to Keep the Pregnancy

“…Recent retrospective analysis of prospectively collected data from women with placenta previa and at least one previous cesarean delivery or uterine surgery reported that early first-trimester (5–7 weeks’ gestation) sonographic assessment of pregnancies with previous cesarean delivery can predict the ultrasound stage of placenta accreta spectrum disorder [ 14 ]. Three sonographic markers for first-trimester assessment of CSP were analyzed: Already mentioned crossover sign (reported by Cali et al), implantation of the gestational sac on the scar vs. in the niche of the cesarean scar (reported by Kaelin Agten et al), and position of the center of the gestational sac below vs. above the midline of the uterus (reported by Timor-Tritsch et al).…”

Association of hemorrhage at termination in caesarean scar pregnancy using the crossover sign of ultrasound image

“…The COS is a new sonographic sign that indicates the relationship between the gestational sac of the CSP, anterior uterine wall and caesarean scar was used 7 . Previous studies 8,9 have reported that the crossover sign (COS) is independent risk factors for severe bleeding in CSP. The COS can predict the risk of adverse outcomes in CSP patients.…”