Cesarean Scar Defect
Conditions
Keywords
Isthmocele
Brief summary
The goal of this trial is to examine if the completion or omission of a bladder flap impacts the location and formation of cesarean scar niche in women undergoing primary cesarean section. The main question it aims to answer is if omission of a bladder flap changes the prevalence of cesarean scar niche on a 6-8 week postpartum ultrasound. Researchers will compare participants that have a bladder flap made to those that have a bladder flap omitted at time of their primary cesarean delivery. Participants will have routine postpartum care and be asked to return for a 6-8 week postpartum transvaginal ultrasound.
Detailed description
As the rate of cesarean deliveries increases globally, the importance of a cesarean scar niche (CSN) has evolved into a significant clinical concern with long term obstetric and gynecologic implications including increasing risk for placenta accreta spectrum (PAS) in future pregnancies and abnormal uterine bleeding. In fact, the main cause of PAS is placentation into uterine scars secondary to cesarean deliveries Bladder flap formation is a standard step in cesarean deliveries and involves dissecting the bladder off the uterus to push it inferiorly to allow better access to the lower uterine segment for hysterotomy and decrease risk of bladder injury. The lower uterine segment is targeted for hysterotomy as it has been shown that the proportion of muscle tissue and the thickness of the wall of the uterus increases as one travels from the cervix to the fundus. Therefore, by making an incision in the lower uterine segment, the surgeon has less tissue to go through to deliver the fetus and disrupts less muscle to preserve uterine myometrial integrity. While studies have suggested bladder flap omission in primary cesarean deliveries does not increase intraoperative complications and reduces operating time. CSN assessment was not an outcome evaluated in these studies and the decision to omit or perform a bladder flap is at the discretion of the surgeon. Previous studies have looked at different surgical techniques and different cervical dilations at time of cesarean delivery and the impact on niche formation and location. There has been no consensus on hysterotomy or other surgical techniques to decrease risk of CSN formation. To our knowledge, there have not been studies that have assessed postoperative CSN in relation to completion or omission of a bladder flap prior to hysterotomy. As such, the investigator team hypothesizes that omission of a bladder flap lends itself to a more cephalad hysterotomy and potentially more clinically significant CSNs.
Interventions
PROCEDUREBladder flap formation
Participants in this arm will have a bladder flap completed at the time of their cesarean delivery.
Sponsors
Montefiore Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Intervention model description
Participants will be randomized in a 1:1 ratio into two treatment groups one undergoing bladder flap formation and the other undergoing bladder flap omission
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 18 years or older * Primary low transverse cesarean section performed at Montefiore Weiler or Wakefield Hospitals * Able to provide informed consent in English or Spanish * Plan for postpartum care at Montefiore Medical Center
Exclusion criteria
* History of a prior uterine surgery * Known congenital uterine anomalies * Inability to safely access lower uterine segment at time of delivery * Hysterotomy is extended past/outside the lower uterine segment at time of surgery * Hysterectomy is indicated prior to postpartum follow-up
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Presence of cesarean scar niche | From enrollment to transvaginal ultrasound, completed approximately 6-8 weeks postpartum | A dichotomous measure of the presence or absence of a cesarean scar niche, as defined by a residual myometrial thickness of \<3mm at the scar level, detected on transvaginal ultrasound. The presence of a cesarean scar niche increases risk for gynecologic complaints and abnormal placentation in subsequent pregnancies. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Distance of cesarean scar niche from internal os | From enrollment to time of transvaginal ultrasound, completed approximately 6-8 weeks postpartum | Sonographic distance of cesarean scar niche from internal cervical os, measured in millimeters, on postpartum transvaginal ultrasound. The investigator team hypothesizes that a scar further from the internal os has increased risk for abnormal placentation in future pregnancies. |
| Size of cesarean scar niche | From enrollment to time of transvaginal ultrasound, completed approximately 6-8 weeks postpartum | Sonographic dimensions of length and width of cesarean scar niche, measured in mm, on transvaginal ultrasound. The investigator team hypothesizes that larger niches are associated with increased risk of abnormal placentation in future pregnancies and increased risk of future gynecologic complaints. |
| Measurement of residual myometrium | From enrollment to time of transvaginal ultrasound, completed approximately 6-8 weeks postpartum | Sonographic measurement of residual myometrium in mm by transvaginal ultrasound. Thinner residual myometrium may imply a larger defect, increased risk for abnormal placentation or formation of a uterine window in future pregnancies. |
| Size of cesarean scar defect in subsequent pregnancy | From time of enrollment to time of subsequent pregnancy, up to 5 years following baseline pregnancy | Sonographic measurement of dimensions (length and width) of cesarean scar defect in subsequent pregnancy, measured in mm, to assess if larger postpartum niches are associated with larger defects in subsequent pregnancies as they may carry increased risk of morbidity in the pregnancy. |
| Cases of abnormal placentation in subsequent pregnancies | From time of enrollment to time of subsequent pregnancy, up to 5 years following baseline pregnancy | If encountered in a subsequent pregnancy, the number of cases of abnormal placentation in the cesarean scar and placenta accreta spectrum will be summarized. Ultrasound evidence of placenta accreta spectrum include disappearance of the border between placenta and myometrium, placental lacunae, increased vasculature from placenta extending into myometrium, abnormal invasion of placenta into surrounding organs and structures. Pathology will be used to confirm the number of cases of placenta accreta spectrum. |
| Uterine Position/Flexion | From enrollment to time of transvaginal ultrasound, completed approximately 6-8 weeks postpartum | As an anteverted and retroflexed uterus is commonly the result of a cesarean delivery and scar tissue altering anatomical position, the clinicians will observe if a bladder flap alters position of the uterus. At the 6 week transvaginal ultrasound, the position of the uterus as anteverted or retroverted and flexion as anteflexed or retroflexed will be recorded. In the sagittal plane on transvaginal ultrasound, if the cervix appears on the viewer's right or left, the position is anteverted or retroverted, respectively. The anterior or posterior flexion of the fundus will define anteflexion and retroflexion, respectively |
| Number/percentage of Operative and Postoperative Complications | From enrollment to time of transvaginal ultrasound, completed approximately 6-8 weeks postpartum | Patient charts will be reviewed to summarize the number/percentage of surgical complications in each arm. This includes complications such as damage to surrounding structures, hemorrhage, hematoma formation, surgical site infections. |
Countries
United States
Contacts
CONTACTAlyssa Yeung, MD
PRINCIPAL_INVESTIGATORPe'er Dar, MD
Montefiore Medical Center
Outcome results
None listed