Evaluation of Cervical Invasion and Length in Placenta Accreta Patients

Evaluation of Placental Cervical Invasion and Cervical Length in Patients With Placenta Accreta

Placenta accreta spectrum (PAS), also called morbidly adherent placenta, is a serious pregnancy problem where the placenta attaches too deeply to the uterus wall and does not come out normally after birth. This often happens after previous cesarean sections or when the placenta is low (placenta previa). It can cause heavy bleeding, serious complications, and danger to the mother.

This study will look at pregnant women with PAS at Sohag University Hospital in Egypt. Researchers will use ultrasound to check two things:

How much the placenta has invaded the cervix (the lower part of the uterus). The length of the cervix.

The main goals are to find out:

How common cervical invasion is in PAS cases. What happens to women who have this invasion (outcomes like bleeding or surgery needs).

If a short cervix is linked to early labor (preterm birth). Women with confirmed PAS will join this observational study from March 2026 to January 2028. They will have extra ultrasound scans during pregnancy. No new treatments or drugs are tested - the study only collects information from routine care and scans to better understand the condition.

This research may help doctors predict risks earlier, plan safer deliveries, and improve care for mothers and babies with PAS in the future.

Study Overview

• Status: Not yet recruiting
• Conditions: Placenta Accreta Spectrum; Placenta Accreta; Placenta Previa

Detailed Description

Placenta accreta spectrum (PAS), previously termed morbidly adherent placenta, includes a spectrum of disorders characterized by abnormal adherence of placental tissue to or invasion into the myometrium, frequently associated with prior cesarean deliveries and placenta previa. The rising incidence of PAS correlates with increasing cesarean section rates worldwide, posing substantial risks such as massive postpartum hemorrhage, surgical complications, organ injury (e.g., bladder), and maternal mortality.

Cervical invasion in PAS involves extension of placental tissue into the cervical stroma or cervico-isthmic complex, potentially leading to fibrosis in the lower posterior cervical-trigonal space. This feature complicates surgical management and heightens risks of uncontrollable bleeding and adjacent organ damage. Although cervical involvement has been underrecognized as a distinct entity in many prior studies, emerging evidence links fibrosis-associated cervico-trigonal invasion to severe morbidity.

Additionally, cervical length (CL) assessment in PAS patients has shown that a short CL (≤30 mm) is associated with increased risk of massive intraoperative hemorrhage. Retrospective data suggest CL as a predictor of unscheduled deliveries and preterm birth in this population.

The current study introduces a novel multidisciplinary protocol integrating prospective evaluation of placental cervical invasion (via ultrasound) and cervical length measurement in PAS patients. This combined approach aims to provide a unified framework for enhanced risk stratification, better anticipation of complications, and optimization of surgical planning to minimize unscheduled interventions and improve maternal and neonatal outcomes.

Aim of the study To estimate the incidence of cervical invasion in placenta accreta spectrum patients, assess outcomes in those cases, evaluate cervical length in PAS patients, and investigate its relation to preterm labor.

Patients and Methods This is a prospective observational (conservative) study enrolling women diagnosed with placenta accreta spectrum. Recruitment will occur from March 2026 to January 2028 at Sohag University Hospital, a tertiary referral center in Sohag Governorate, Egypt. The hospital features advanced obstetric imaging capabilities, multidisciplinary teams including maternal-fetal medicine specialists, and neonatal intensive care support for high-risk pregnancies.

Eligible participants are pregnant women with confirmed PAS (based on prenatal ultrasound/MRI criteria). Study procedures involve serial transvaginal and transabdominal ultrasound assessments to measure cervical length and evaluate the extent of placental cervical invasion. Data will include demographic details, obstetric history, imaging findings, delivery mode, intraoperative complications, blood loss, and maternal/neonatal outcomes. No interventional treatments are introduced; management follows standard institutional protocols for PAS.

• Study Type: Observational
• Enrollment (Estimated): 200

Contacts and Locations

• Study Contact: Name: Ahmed Salah Salah Ali, Assistant lecturer; Phone Number: +201050199550; Email: ahmedsalahali37@yahoo.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Screen high-risk pregnant women presenting at 18:32 weeks' gestation via history and initial transabdominal ultrasound for PAS risk factors (e.g., placenta previa, prior cesarean). -Obtain informed consent and perform baseline laboratory tests (e.g., complete blood count, coagulation profile). -Ultrasonographic Evaluation for Cervical Invasion: *Perform transvaginal ultrasound (TVUS) using a high-frequency probe (e.g., 5-9 MHz) in a standardized manner, ensuring patient comfort and safety (e.g., empty bladder, lithotomy position). *Assess for standard PAS markers first: loss of retroplacental clear zone, myometrial thinning <1 mm, placental lacunae (Swiss cheese appearance), abnormal utero-placental hypervascularity, bridging vessels, and placental bulge .

Description

Inclusion Criteria:

• Pregnant women aged 18-45 years with suspected or confirmed PAS based on prenatal ultrasound (e.g., placenta previa with at least one prior cesarean section).
• Gestational age between 18-32 weeks at enrollment to allow for serial monitoring.
• Singleton pregnancy.
• High-risk features such as history of multiple cesarean sections, antepartum bleeding, or abnormal placental location on initial screening.

Exclusion Criteria:

• Multiple gestation.
• Pre-existing cervical incompetence or cerclage placement prior to enrollment. -Transfer from outside facilities without complete prenatal records.

Study Plan

How is the study designed?

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort
PAS patients with cervical invasion; Have cervical invasion using criteria compiled from multiple studies: ٭Extension of placental tissue into the cervical stroma or cervico-isthmic complex (CIC), with placental tissue encroaching on or beyond the internal os without clear separation . ٭Irregular cervical contour or disruption of the normal cervical architecture, including fibrosis in the lower posterior cervical-trigonal space (associated with type 4 PAS and higher morbidity) . ٭Increased vascularity within the cervical canal or stroma, detected via color Doppler showing turbulent flow or lacunae extending into the cervix (predictive of deep invasion and bleeding risk) . ٭Presence of intracervical lakes (novel marker: hypoechoic or anechoic spaces within the cervical tissue, suggestive of invasive placentation) .
PAS patients without cervical invasion; Haven't cervical invasion using criteria compiled from multiple studies: ٭Extension of placental tissue into the cervical stroma or cervico-isthmic complex (CIC), with placental tissue encroaching on or beyond the internal os without clear separation . ٭Irregular cervical contour or disruption of the normal cervical architecture, including fibrosis in the lower posterior cervical-trigonal space (associated with type 4 PAS and higher morbidity) . ٭Increased vascularity within the cervical canal or stroma, detected via color Doppler showing turbulent flow or lacunae extending into the cervix (predictive of deep invasion and bleeding risk) . ٭Presence of intracervical lakes (novel marker: hypoechoic or anechoic spaces within the cervical tissue, suggestive of invasive placentation) . Scoring systems integration:
PAS patients with short cervical length; Cervical length will be measured in admission and before delivery The final CL measurement prior to delivery was analyzed. Unscheduled delivery was defined as urgent delivery prior to the scheduled date due to either bleeding or preterm contractions. A receiver operating characteristics (ROC) curve was created, the optimal CL associated with unscheduled delivery was selected, and associations and prediction analyses were performed. Short cl < 3 cm
PAS patients with normal cervical length; Cervical length will be measured in admission and before delivery The final CL measurement prior to delivery was analyzed. Unscheduled delivery was defined as urgent delivery prior to the scheduled date due to either bleeding or preterm contractions. A receiver operating characteristics (ROC) curve was created, the optimal CL associated with unscheduled delivery was selected, and associations and prediction analyses were performed. Short cl ≥ 3 cm

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative findings regarding cervical invasion of placenta .	Visible placental tissue extending into or through the lower uterine segment and cervix, sometimes protruding into the cervical canal or os. Bluish/purple discoloration or bulging/distension ("bulge sign") of the lower uterine segment and cervical area due to underlying placental invasion. Prominent hypervascularity: Dense, tangled vessels (often large, tortuous, or engorged) running over the serosal surface of the lower uterus and cervix; this includes abnormal neovascularization or "rail sign"-like patterns. Adherent placenta that does not separate easily; attempts at gentle cord traction may show the "dimple sign" (uterus pulled inward without placental release). Thinned or disrupted myometrium in the lower segment/cervix, with placental villi directly attached or invading deeply (no clear cleavage plane). In more severe (percreta-like) cases involving the cervix: Placental protrusion or exophytic growth through the serosa. and confirmed by histopathology	Intraoperative
timing of delivery	Gestational age in weeks and days at the time of delivery (calculated from last menstrual period or early ultrasound dating) to note the preterm labour and its association with cervical length	At delivery
Cervical length before delivery	Cervical length will be measured immediately before delivery by ultrasound to estimate relation between short cervical length and preterm labor	Immediately prior to delivery
Hysterectomy rate	Number of CS hysterectomy done for the patients of placenta accreta spectrum with cervical invasion	Intraoperative

Collaborators and Investigators

• Sponsor: Sohag University
• Investigators: Principal Investigator: Ahmed Salah Ali, MSC, Sohag University

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2028

Study Registration Dates

• First Submitted: February 22, 2026
• First Submitted That Met QC Criteria: March 1, 2026
• First Posted (Actual): March 5, 2026

Study Record Updates

• Last Update Posted (Actual): March 5, 2026
• Last Update Submitted That Met QC Criteria: March 1, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Preterm labor; Placenta accreta; Cervical length; Ultrasound evaluation; Placenta accreta spectrum; Cervical invasion
• Additional Relevant MeSH Terms: Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Obstetric Labor Complications; Pregnancy Complications; Placenta Diseases; Placenta Previa; Obstetric Labor, Premature; Placenta Accreta
• Other Study ID Numbers: Soh-Med--26-2-3MD

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No