Transvaginal Sonographic Evaluation of Cesarean Section Scar Niche in Pregnancy: A Prospective Longitudinal Study

Background and Objectives: To investigate the prevalence of a Cesarean section (CS) scar niche during pregnancy, assessed by transvaginal ultrasound imaging, and to relate scar measurements, demographic and obstetric variables to the niche evolution and final pregnancy outcome. Materials and Methods: In this prospective observational study, we used transvaginal sonography to examine the uterine scars of 122 women at 11⁺⁰–13⁺⁶, 18⁺⁰–20⁺⁶ and 32⁺⁰–35⁺⁶ weeks of gestation. A scar was defined as visible on pregnant status when the area of hypoechogenic myometrial discontinuity of the lower uterine segment was identified. The CS scar niche (“defect”) was defined as an indentation at the site of the CS scar with a depth of at least 2 mm in the sagittal plane. We measured the hypoechogenic part of the CS niche in two dimensions, as myometrial thickness adjacent to the niche and the residual myometrial thickness (RMT). In the second and third trimesters of pregnancy, the full lower uterine segment (LUS) thickness and the myometrial layer thickness were measured at the thinnest part of the scar area. Two independent examiners measured CS scars in a non-selected subset of patients (n = 24). Descriptive analysis was used to assess scar visibility, and the intraclass correlation coefficient (ICC) was calculated to show the strength of absolute agreement between two examiners for scar measurements. Factors associated with the CS scar niche, including maternal age, BMI, smoking status, previous vaginal delivery, obstetrics complications and a history of previous uterine curettage, were investigated. Clinical information about pregnancy outcomes and complications was obtained from the hospital’s electronic medical database. Results: The scar was visible in 77.9% of the women. Among those with a visible CS scar, the incidence of a CS scar niche was 51.6%. The intra- and interobserver agreement for CS scar niche measurements was excellent (ICC 0.98 and 0.89, respectively). Comparing subgroups of women in terms of CS scar niche (n = 49) and non-niche (n = 73), there was no statistically significant correlation between maternal age (p = 0.486), BMI (p = 0.529), gestational diabetes (p = 1.000), smoking status (p = 0.662), previous vaginal delivery after CS (p = 1.000) and niche development. Uterine scar niches were seen in 56.3% (18/48) of the women who had undergone uterine curettage, compared with 34.4% (31/74) without uterine curettage (p = 0.045). We observed an absence of correlation between the uterine scar niche at the first trimester of pregnancy and mode of delivery (p = 0.337). Two cases (4.7%) of uterine scar dehiscence were confirmed following a trial of vaginal delivery. Conclusions: Based on ultrasonography examination, the CS scar niche remained visible in half of the cases with a visible CS scar at the first trimester of pregnancy and could be reproducibly measured by a transvaginal scan. Previous uterine curettage was associated with an increased risk for uterine niche formation in a subsequent pregnancy. Uterine scar dehiscence might be potentially related to the CS scar niche.

Symptomatic Uterine Rupture: A Fifteen Year Review

Background and objectives: To assess the incidence of complete and partial uterine rupture during childbirth in a single tertiary referral centre as well as the significant risk factors, symptoms and peripartum complications. Materials and Methods: A retrospective single-centre study involved all cases of uterine rupture at the Kaunas Perinatal Centre in 2004–2019. Data were from a local medical database complemented with written information from medical records. We included 45,893 women with an intact uterus and 5630 with uterine scars. Women (n = 5626) with scarred uterus’ after previous cesarean delivery. The diagnosis was defined by clinical symptoms, leading to an emergency cesarean delivery, when complete or partial uterine rupture (n = 35) was confirmed. Asymptomatic cases, when uterine rupture was found at elective cesarean section (n = 3), were excluded. The control group is represented by all births delivered in our department during the study period (n = 51,525). The outcome was complete (tearing of all uterine wall layers, including serosa and membranes) and partial uterine rupture (uterine muscle defect but intact serosa), common uterine rupture symptoms. Risk factors were parameters related to pregnancy and labour. Results: 51,525 deliveries occurred in Kaunas Perinatal Centre during the 15 years of the study period. A total number of 35 (0.06%) symptomatic uterine ruptures were recorded: 22 complete and 13 partial, leading to an incidence rate of 6.8 per 10,000 deliveries. The uterine rupture incidence rate after a single previous cesarean delivery is 44.4 per 10,000 births. 29 (83%) cases had a uterine scar after previous cesarean, 4 (11%) had a previous laparoscopic myomectomy, 2 (6%) had an unscarred uterus. The most significant risk factors of uterine rupture include uterine scarring and augmentation or epidural anaesthesia in patients with a uterine scar after cesarean delivery. The most common clinical sign was acute abdominal pain in labour 18 (51%). No maternal, six intrapartum perinatal deaths (17%) occurred, and one hysterectomy (2.8%) was performed due to uterine rupture. Neonatal mortality reached 22% among the complete ruptures. Average blood loss was 1415 mL, 4 (11%) patients required blood transfusion. Conclusions: The incidence rate of uterine rupture (complete and incomplete) at Kaunas Perinatal Centre is 6.8 per 10,000 deliveries. In cases with a scar of the uterus after a single cesarean, the incidence of uterine rupture is higher, exceeding 44 cases per 10,000 births. The most significant risk factors were uterine scar and augmentation or epidural anaesthesia in a previous cesarean delivery. Acute abdominal pain in labour is the most frequent symptom for uterine rupture.

Resolution of Fetal Hydrops Dependent on Sustained Fetal Supraventricular Tachycardia after Digoxin Therapy

We present a special case of fetal supraventricular tachycardia detected at 34 weeks gestation. Fetal hydrops was noted on ultrasound upon admission. Normal fetal heart rate was maintained for three weeks by maternal administration of digoxin. A live infant was delivered via caesarian section at 37 weeks gestation. This clinical case demonstrated that pharmacological treatment can be effective and helps to prolong pregnancy safely.