Development of the utero-placental circulation in cesarean scar pregnancies: A case-control study

BACKGROUND: Cesarean scar pregnancies (CSP) are at high risk of pregnancy complications including placenta previa with antepartum hemorrhage, placenta accreta spectrum (PAS) and uterine rupture. OBJECTIVE: To evaluate the development of the utero-placental circulation in the first half of pregnancy in ongoing CSP and compare it to pregnancies implanted in the lower uterine segment above a prior cesarean section scar with no evidence of PAS at delivery. MATERIAL AND METHODS: This was a retrospective case-control study conducted in two tertiary referral centers. The study group included 27 women diagnosed with a live caesarean scar pregnancy in the first trimester of pregnancy who elected to conservative management. The control group included 27 women diagnosed with a low-lying/placenta previa at 19-22 weeks of gestation who had a first and an early second trimester ultrasound examinations. In both groups, the first ultrasound examination was carried out at 6-10 weeks to establish pregnancy location, viability and to confirm the gestational age. The utero-placental and intra-placental vasculatures were examined using color Doppler imaging (CDI) and described semi quantitatively using CDI score 1-4. The remaining myometrial thickness (RMT) was recorded in the study group whereas in the controls the ultrasound features of prior cesarean scar were noted including the presence of a niche. Both CSP and controls had also ultrasound examinations at 11-14 and 19-22 weeks of gestation. RESULTS: The mean CDI vascularity score at the 6-10 weeks ultrasound examination was significantly (P <.001) higher in the CSP group than in the controls. The high vascularity scores 3 and 4 were recorded in 20/27 (74%) cases of the CSP group. There was no vascularity score of 4 and only 3/27 (11%) controls had vascularity score of 3. In 15/27 (55.6%) CSPs the RMT was < 2 mm. At the 11-14 weeks ultrasound examination, there was no significant difference between the groups for the number of cases with increased subplacental vascularity but 12 CSPs (44%) presented with one or more placental lacunae whereas there was no case with lacunae in the controls. In the 18 CSP that progressed into the third trimester, ten were diagnosed with placenta previa creta at birth, including 4 creta and 6 increta. At the 19-22 weeks ultrasound examination, eight of the ten PAS presented with subplacental hypervascularity out of which, six showed also placental lacunae. CONCLUSION: The vascular changes in the utero-placental and intervillous circulations in CSPs are due to the loss of the normal uterine structure in the scar area and the development of placental tissue in proximity of large diameter arteries of the outer uterine wall. The intensity of these vascular changes, development of PAS and risk of uterine rupture depend on the RMT of the cesarean scar defect at the start of pregnancy. A better understanding of the pathophysiology of the utero-placental vascular changes associated with CSP should help in identifying those cases that may develop major complications and thus contribute to counselling women about the risks associated with different management strategies

A new methodologic approach for clinico-pathologic correlations in invasive placenta previa accreta

BACKGROUND: The development of new management strategies for women presenting with placenta accreta spectrum requires quality epidemiology data which have so far been limited by the high variability in clinical and histopathologic data confirming the diagnosis at birth. OBJECTIVE: To evaluate the role of a new methodologic approach for the correlation of clinical and pathological data for women with a history of prior cesarean delivery diagnosed prenatally with placenta previa accreta. STUDY DESIGN: A modified pathologic technique for gross examination of hysterectomy specimens with placenta in-situ consisting of intra-operative examination, immediate post-operative examination and guided histologic sampling was used prospectively in a cohort of 24 patients with singleton pregnancies complicated by placenta low-lying/placenta previa accreta. The maternal characteristics, detailed ultrasound findings, surgical outcomes and histopathologic examination were compared with those of a group of 24 patients with similar clinical characteristics where a standard pathologic examination method was used. RESULTS: The median reporting time for obtaining the complete histopathology results including the microscopic examination was significantly shorter (7 vs 15 days; P<0.001) and the median number of samples taken for histologic examination significantly lower (4 vs 14 samples; P<0.001) in the study group than in the controls. The number of histologic slides showing villous invasion was significantly higher (2 vs 1 slides; P=0.002) and the ratio of the number of samples taken to the numbers of slides confirming villous invasion was significantly lower (2 vs 9; P<0.001) in the study group than in the controls. In all cases of the study group, intra-operative examination identified a dense tangled bed of vessels or multiple vessels running laterally and cranio-caudally in the uterine serosa above the placental insertion which were no longer visible during immediate gross post-operative examination of the hysterectomy specimens. Immediate post-operative dissection enables the differential diagnosis between focal and large increta areas, and between abnormally adherent placenta and invasive placenta accreta. CONCLUSIONS: Valuable clinical information on the serosal vascularity, uterine dehiscence and extension of the accreta area is added with the description of the macroscopic examination during the surgical procedure and immediate dissection of the specimen. This methodological approach is cost-effective and increases the quality of the histologic sampling. It thus provides more accurate correlations with the clinical data and more accurate epidemiologic data collection. Perinatal pathologists should be part of multidisciplinary teams involved the management placenta accreta spectrum disorders

Epidemiological and cohort study finds no association between COVID-19 and Guillain-Barré syndrome

Reports of Guillain-Barré syndrome (GBS) have emerged during the Coronavirus disease 2019 (COVID-19) pandemic. This epidemiological and cohort study sought to investigate any causative association between COVID-19 infection and GBS. The epidemiology of GBS cases reported to the UK National Immunoglobulin Database was studied from 2016 to 2019 and compared to cases reported during the COVID-19 pandemic. Data were stratified by hospital trust and region, with numbers of reported cases per month. UK population data for COVID-19 infection were collated from UK public health bodies. In parallel, but separately, members of the British Peripheral Nerve Society prospectively reported incident cases of GBS during the pandemic at their hospitals to a central register. The clinical features, investigation findings and outcomes of COVID-19 (definite or probable) and non-COVID-19 associated GBS cases in this cohort were compared. The incidence of GBS treated in UK hospitals from 2016 to 2019 was 1.65–1.88 per 100 000 individuals per year. GBS incidence fell between March and May 2020 compared to the same months of 2016–19. GBS and COVID-19 incidences during the pandemic also varied between regions and did not correlate with one another (r = 0.06, 95% confidence interval: −0.56 to 0.63, P = 0.86). In the independent cohort study, 47 GBS cases were reported (COVID-19 status: 13 definite, 12 probable, 22 non-COVID-19). There were no significant differences in the pattern of weakness, time to nadir, neurophysiology, CSF findings or outcome between these groups. Intubation was more frequent in the COVID-19 affected cohort (7/13, 54% versus 5/22, 23% in COVID-19-negative) attributed to COVID-19 pulmonary involvement. Although it is not possible to entirely rule out the possibility of a link, this study finds no epidemiological or phenotypic clues of SARS-CoV-2 being causative of GBS. GBS incidence has fallen during the pandemic, which may be the influence of lockdown measures reducing transmission of GBS inducing pathogens such as Campylobacter jejuni and respiratory viruses

Fetal blood sampling from intrahepatic vein versus cord insertion: effect on PH and blood gases

Objective: To determine whether venous pH, base excess, and blood gas values collected by antenatal ultrasound-guided sampling from the fetal intrahepatic vein (intraabdominal umbilical vein, portal sinus, or portal vein) differ from those obtained from the placental cord insertion

Incidence of major structural cardiac defects associated with increased nuchal translucency but normal karyotype

Objective: To examine the association between increased nuchal translucency thickness and major cardiac defects in chromosomally normal fetuses. Setting: Tertiary referral unit for fetal medicine and fetal cardiology. Methods: During a 4-year period (January 1997 to January 2001), detailed echocardiography was performed in 1319 chromosomally normal fetuses with increased nuchal translucency thickness at 10-14 weeks of gestation. The incidence of major cardiac defects was examined in relation to the fetal NT at the 10-14-week scan. Results: Major cardiac defects were diagnosed in 60 (4.5%) of the 1319 fetuses. In fetuses with a nuchal translucency thickness in the range of 2.5-3.4 mm, the incidence of major cardiac defects was 2.5% (18/722; 95% confidence interval, 1.5-3.9) and in those with a nuchal translucency thickness ≥3.5 mm, it was 7% (42/597; 95% confidence interval, 5.1-9.4). Conclusion: Specialist echocardiography is indicated in all fetuses with increased nuchal translucency thickness because, in such fetuses, the incidence of major cardiac defects is substantially higher than in pregnancies with maternal diabetes, family history and exposure to drugs, where fetal echocardiography is widely considered to be necessary

Clinical and echographic features of in utero cardiac dysfunction in the recipient twin in twin-twin transfusion syndrome.

OBJECTIVE--Fetal twin-twin transfusion syndrome (TTTS) presenting in the second trimester has been associated with almost no perinatal survival until recently, when serial drainage of amniotic fluid has improved the prognosis to 70%-80%. Most recipient twins now survive but develop cardiac dysfunction. The study was undertaken to evaluate the abnormal echocardiographic features and clinical complications of cardiac disease in the recipient twin of TTTS. DESIGN--Antenatal and postnatal echocardiographic and clinical observational study. SETTING--Antenatal studies in a tertiary referral centre. Postnatal management and follow up were performed by the same paediatric cardiologist, either at the obstetric hospital or at the regional referral centre. PATIENTS--Twin pregnancies complicated by TTTS with severe polyhydramnios diagnosed earlier than 25 weeks that proceeded until viability (n = 5). INTERVENTION--Serial fetal echocardiography with colour Doppler. Postnatal echocardiography in the first week and between two and seven months. Serial amnioreduction was performed in all pregnancies. Digoxin treatment, pericardiocentesis, paracentesis, or laser ablation of placental anastomoses was undertaken when there was hydrops. RESULTS--Increased cardiothoracic ratio and tricuspid regurgitation were seen in all recipient twins. High pulmonary artery velocities developed in three. One recipient twin died a week after delivery of endocardial fibroelastosis and infundibular pulmonary stenosis. Two other had balloon dilatation for pulmonary stenosis, one shortly after birth and one at four months. A further twin has apical thickening of the right ventricle at six months. The remaining recipient twin had normal echocardiographic findings at follow up. CONCLUSION--This report characterises for the first time a cardiac disease acquired in utero in the recipient twin in pregnancies complicated by TTTS. Clinical manifestations in utero range from mild to critical pulmonary stenosis or lethal cardiomyopathy. Although perinatal prognosis seems to be related to the severity of dysfunction when first diagnosed in utero, follow up in infancy is recommended in view of the possibility of progressive pulmonary stenosis

Impact of placenta previa with placenta accreta spectrum disorder on fetal growth

Objectives: To evaluate fetal growth in pregnancies complicated by placenta previa, both with and without PAS, compared to pregnancies with just a low‐lying placenta. Methods: This was a multicentre retrospective cohort study of singleton pregnancies complicated by placenta previa, both with and without placenta accreta spectrum (PAS), for which maternal characteristics, ultrasound estimated fetal weight and birthweight were available. The control group chosen was singleton pregnancies with a low‐lying placenta (0.5‐2cm from the internal os). For comparison, the study groups were matched for smoking status, ethnic origin and gestational age at delivery. The diagnosis of PAS and depth of invasiveness was confirmed at birth using both a pre‐defined clinical grading score and histopathological examination. Four maternal‐fetal medicine units participated in data collection of diagnosis, treatment, and outcomes. Results: The study included 82 women with previa‐PAS, subdivided into adherent previa‐PAS (n= 35) and invasive previa‐PAS (n= 47) and 146 women with a placenta previa. There were 64 controls with a low‐lying placenta. There was no significant difference in the incidence of small‐for‐gestational age (SGA) and large‐for‐gestational age (LGA) between the study groups at the different percentiles cut‐off values. The median gestational age at diagnosis was significantly (P=0.002) lower in the placenta previa than in the low‐lying placenta group. No significant difference was found between previa‐PAS and placenta previa groups for any of the variables. The median EFW percentile was significantly higher in the adherent compared to the invasive subgroup (P= 0.048). The actual birthweight percentiles at delivery did not differ significantly (P= 0.804) between the subgroups. Conclusions: No difference was seen in fetal growth for pregnancies with a previa‐PAS when compared with placenta previa and low‐lying placenta. There was also no increased incidence of either SGA or LGA babies when a placenta previa was complicated by PAS when compared to a previa which separated spontaneously at birth. Neonatal outcome in previa‐PAS is linked to premature delivery and not to impaired fetal growth.</p