Single-layer vs double-layer uterine closure during cesarean delivery: 3-year follow-up of a randomized controlled trial (2Close study)

BACKGROUND

The rising rate of cesarean deliveries has led to an increased incidence of long long-term complications, including niche formation in the uterine scar. Niche development is associated with various gynecologic complaints and complications in subsequent pregnancies, such as uterine rupture and placenta accreta spectrum disorders. Although uterine closure technique is considered a potential risk factor for niche development, consensus on the optimal technique remains elusive.

OBJECTIVE

We aimed to evaluate the effect of single-layer vs double-layer closure of the uterine incision on live birth rate at a 3-year follow-up with secondary objectives focusing on gynecologic, fertility, and obstetrical outcomes at the same follow-up.

STUDY DESIGN

A multicenter, double-blind, randomized controlled trial was performed at 32 hospitals in the Netherlands. Women ≥18 years old undergoing a first cesarean delivery were randomly assigned (1:1) to receive either single-layer or double-layer closure of the uterine incision. The primary outcome of the long-term follow-up was the live birth rate; with secondary outcomes, including pregnancy rate, the need for fertility treatment, mode of delivery, and obstetrical and gynecologic complications. This trial is registered on the International Clinical Trials Registry Platform www.who.int (NTR5480; trial finished).

RESULTS

Between 2016 and 2018, the 2Close study randomly assigned 2292 women, with 830 of 1144 and 818 of 1148 responding to the 3-year questionnaire in the single-layer and double-layer closure. No differences were observed in live birth rates; also there were no differences in pregnancy rate, need for fertility treatments, mode of delivery, or uterine ruptures in subsequent pregnancies. High rates of gynecologic symptoms, including spotting (30%-32%), dysmenorrhea (47%-49%), and sexual dysfunction (Female Sexual Function Index score, 23) are reported in both groups.

CONCLUSION

The study did not demonstrate the superiority of double-layer closure over single-layer closure in terms of reproductive outcomes after a first cesarean delivery. This challenges the current recommendation favoring double-layer closure, and we propose that surgeons can choose their preferred technique. Furthermore, the high risk of gynecologic symptoms after a cesarean delivery should be discussed with patients.

Aetiology, risk factors and preventive strategies for niche development: A review

The increase in caesarean sections (CS) has resulted in an increase in women with a uterine niche. The exact aetiology of niche development has yet to be elucidated but is likely multifactorial. This study aimed to give a systematic overview of the available literature on histopathological features, risk factors and results of preventive strategies on niche development to gain more insight into the underlying mechanisms. Based on current published data histopathological findings associated with niche development were necrosis, fibrosis, inflammation, adenomyosis and insufficient approximation. Patient-related risk factors included multiple CS, BMI and smoking. Labour-related factors were CS before onset of labour, extended cervical dilatation, premature rupture of membranes and presenting part of the fetus at CS below the pelvic inlet. Preventive strategies should focus on the optimal level of incision, training of surgeons and full-thickness closure of the myometrium (single or double-layer) using non-locking sutures. Conflicting data exist concerning the effect of endometrial inclusion. Future studies without heterogeneity in population, using standardized performance of the CS after proper training and using standardized niche evaluation with a relevant core outcome set are required to allow meta-analyses and to develop evidence-based preventive strategies. These studies are needed to reduce the prevalence of niches and prevent complications in subsequent pregnancies such as caesarean scar pregnancies.

Effectiveness, complications, and reproductive outcomes after cesarean scar pregnancy management: a retrospective cohort study

BACKGROUND

There is a dramatic rise in cesarean deliveries worldwide, leading to higher complication rates in subsequent pregnancies. One of these complications is a cesarean scar pregnancy. During the last decades, treatment options for cesarean scar pregnancies have changed, and less invasive interventions have been employed to preserve fertility and reduce morbidity. However, the optimal treatment approach and the influence of various treatments on reproductive outcomes have to be determined.

OBJECTIVE

This study aimed to evaluate the short- and long-term outcomes after cesarean scar pregnancy management.

STUDY DESIGN

We conducted a retrospective cohort study of women determined to have a cesarean scar pregnancy from 2010 to 2021 at a tertiary referral center, the Amsterdam University Medical Center, in the Netherlands. Outcomes of the following management strategies were compared: expectant management, methotrexate, curettage with temporary cervical cerclage, or a laparoscopic niche resection. We performed a curettage if the cesarean scar pregnancy did not cross the serosal line of the uterus, and a laparoscopic niche resection was performed if the cesarean scar pregnancy crossed the serosal line. The main outcomes were treatment efficacy and time to subsequent ongoing pregnancy or pregnancy leading to a live birth.

RESULTS

Of the 60 included women, 5 (8.3%) were managed expectantly, 8 (13.3%) were treated with methotrexate, 31 (51.8%) were treated with a curettage, and 16 (26.7%) with a laparoscopic niche resection. The groups were not comparable. The gestational age and human chorionic gonadotropin levels were generally higher in women who received methotrexate or a laparoscopic niche resection. Additional treatment in the conservative group was needed for 4 (80%) women after expectant management and for 7 (87.5%) women after methotrexate treatment. In the surgical group, all 31 women treated with a curettage and all 16 treated with a laparoscopic niche resection did not require additional treatment. The subsequent ongoing pregnancy rate after cesarean scar pregnancy management was 81.1% (30/37) among women who wished to conceive, with a live birth rate of 78.4% (29/37); 1 woman was in her third trimester of pregnancy at the time of analyses. The time between cesarean scar pregnancy management and subsequent ongoing pregnancy was 4 months (interquartile range, 3-6; P=.02) after expectant management, 18 months (interquartile range, 13-22) after initial methotrexate treatment, 5 months (interquartile range, 3-14; P=.01) after a curettage, and 6 months (interquartile range, 4-15; P=.03) after a laparoscopic niche resection.

CONCLUSION

Surgical treatment of a cesarean scar pregnancy led to a high success rate without additional interventions, high pregnancy rates with a short time interval between treatment, and subsequent pregnancy leading to an ongoing pregnancy or live birth. Conservative management, both with expectant management and methotrexate treatment, led to high (re)intervention rates. Different management approaches are indicated for different types of cesarean scar pregnancies.

Definition and sonographic reporting system for Cesarean scar pregnancy in early gestation: modified Delphi method

OBJECTIVE

To develop a standardized sonographic evaluation and reporting system for Cesarean scar pregnancy (CSP) in the first trimester, for use by both general gynecology and expert clinics.

METHODS

A modified Delphi procedure was carried out, in which 28 international experts in obstetric and gynecological ultrasonography were invited to participate. Extensive experience in the use of ultrasound to evaluate Cesarean section (CS) scars in early pregnancy and/or publications concerning CSP or niche evaluation was required to participate. Relevant items for the detection and evaluation of CSP were determined based on the results of a literature search. Consensus was predefined as a level of agreement of at least 70% for each item, and a minimum of three Delphi rounds were planned (two online questionnaires and one group meeting).

RESULTS

Sixteen experts participated in the Delphi study and four Delphi rounds were performed. In total, 58 items were determined to be relevant. We differentiated between basic measurements to be performed in general practice and advanced measurements for expert centers or for research purposes. The panel also formulated advice on indications for referral to an expert clinic. Consensus was reached for all 58 items on the definition, terminology, relevant items for evaluation and reporting of CSP. It was recommended that the first CS scar evaluation to determine the location of the pregnancy should be performed at 6-7 weeks' gestation using transvaginal ultrasound. The use of magnetic resonance imaging was not considered to add value in the diagnosis of CSP. A CSP was defined as a pregnancy with implantation in, or in close contact with, the niche. The experts agreed that a CSP can occur only when a niche is present and not in relation to a healed CS scar. Relevant sonographic items to record included gestational sac (GS) size, vascularity, location in relation to the uterine vessels, thickness of the residual myometrium and location of the pregnancy in relation to the uterine cavity and serosa. According to its location, a CSP can be classified as: (1) CSP in which the largest part of the GS protrudes towards the uterine cavity; (2) CSP in which the largest part of the GS is embedded in the myometrium but does not cross the serosal contour; and (3) CSP in which the GS is partially located beyond the outer contour of the cervix or uterus. The type of CSP may change with advancing gestation. Future studies are needed to validate this reporting system and the value of the different CSP types.

CONCLUSION

Consensus was achieved among experts regarding the sonographic evaluation and reporting of CSP in the first trimester. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.