The Utility of the Congenital Pulmonary Airway Malformation-Volume Ratio in the Assessment of Fetal Echogenic Lung Lesions: A Systematic Review.

Although relatively uncommon, the incidence of fetal echogenic lung lesions - a heterogeneous group of anomalies that includes congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestrations (BPS) - has increased recently. Two decades ago, the CPAM-volume ratio (CVR) was first described as a tool to predict the development of hydrops, with this outcome found to be unlikely in fetuses with CVRs of ≤1.6 cm2. Since then, no clear international consensus has evolved as to the optimal CVR thresholds for the prediction of fetal/neonatal outcomes. This systematic review aimed to assess all original research studies that reported on the predictive utility of the CVR. Potentially relevant papers were identified through searching for citations of the paper that originally described the CVR, in addition to keyword searches of electronic databases. Fifty-two original research papers were included in the final review. Of these, 34 used the CVR for descriptive purposes only, 5 assessed the validity of established thresholds in different populations, and 13 proposed new thresholds. The evidence identified in this review would suggest that a threshold much lower than 1.6 cm2 is likely to be of greater utility in most populations for many outcomes of perinatal relevance. For neonatal outcomes (mostly respiratory compromise at birth), a CVR on the initial ultrasound scan ranging from 0.5 to 1.0 cm2 appears to have the greatest predictive value. Although a number of studies concurred that 1.6 cm2 was a useful threshold for the prediction of hydrops, many others were unable to assess this due to the rarity of this complication. For this reason, thresholds as low as 0.4 cm2 may be more useful for the prediction of a broader range of fetal concerns, including mediastinal shift and fluid collections. Further large-scale studies are required to determine the true utility of this well-established index.

Hypoplastic nasal bone: A potential marker for facial dysmorphism associated with pathogenic copy number variants on microarray.

OBJECTIVES: To compare the frequency of abnormal genetic diagnoses spanning a period before and after the availability of chromosomal microarray analysis (CMA). We hypothesised that microarray would provide additional clinically relevant information in cases of isolated hypoplastic nasal bone. METHOD: Fetuses with ultrasound-detected hypoplastic nasal bone (absent or <2.5th percentile in length) between 16 and 37 weeks' gestation over a 10-year period were analysed retrospectively. RESULTS: A total of 118 cases of hypoplastic nasal bone met the inclusion criteria. A pathogenic or potentially pathogenic karyotype was detected more frequently in the era where CMA was available (31/60, 52% vs 19/58, 33%). Of these, 25 cases (42%) had common aneuploidies, and six cases (10%) had clinically relevant copy number variants (CNVs). A clinically relevant CNV was detected in two fetuses that presented with isolated hypoplastic nasal bone on initial ultrasound. CONCLUSION: In addition to its known association with trisomy 21, a hypoplastic nasal bone may be an objective marker of facial dysmorphism associated with clinically relevant CNVs. Our results support consideration of invasive testing with microarray for pregnancies in which a hypoplastic nasal bone has been diagnosed on ultrasound irrespective of a low-risk screening result for common chromosomal abnormalities.

Cesarean Scar Pregnancies: Incidence and Factors Associated with Conversion to Surgery from Medical Management.

STUDY OBJECTIVE: To describe the incidence, management, and complications of cesarean scar pregnancy (CSP) and define risk factors for conversion from medical to surgical treatment of CSP. DESIGN: Retrospective clinical study (Canadian Task Force classification II-3). SETTING: Tertiary medical center. PATIENTS: All patients who were admitted and treated for CSP between 2008 and 2016. INTERVENTIONS: The cohort was divided according to management, and demographic, clinical, and sonographic data were collected. Rates of conversion were compared between groups, and risk factors necessitating conversion were sought. MEASUREMENTS AND MAIN RESULTS: Forty-six cases of CSP were identified. The incidence of CSP has increased from 0.05% to 0.09% of all deliveries. A regression model for absolute numbers of CSP predicted an additional 0.47 CSP each year (p = .03). The most common treatment modalities were systemic treatment with methotrexate (28.2%) and ultrasound-guided intrasac injection of KCl with systemic treatment of methotrexate (58.7%). The mean sac diameter (MSD) of cases that were converted was 11.2 mm larger than in cases that were not converted (p < .001). No patients with an MSD <10 mm or a trophoblastic mass <20 mm3 were converted to surgical management. Maximal levels of beta human chorionic gonadotropin (ß-hCG) were significantly associated with the risk of conversion. Only 6.3% of patients with a ß-hCG level <10,000 IU at presentation were converted from medical to surgical management. There was no significant association between fetal cardiac activity and conversion from medical to surgical management. CONCLUSIONS: CSP has emerged as an important phenomenon in modern obstetrics and gynecology, and its frequency appears to be on the rise. The preferred method of treatment remains unclear; however, it is possible that a large MSD and trophoblastic mass at presentation should prompt surgical treatment.

Single Intrauterine Death in Twins: The Importance of Fetal Order.

Perinatal mortality is higher in twins. Effects of twin order have not previously been studied in the context of single fetal demise. Our objective was to determine whether death of the fetus more proximal to the cervix will result in worse perinatal outcomes. Our population included multiple pregnancies with two viable fetuses confirmed prior to 20 weeks' gestation with the subsequent death of at least one twin. All the pregnancies were managed at The Royal Women's Hospital, Melbourne between 2006 and 2014. We excluded pregnancies of higher order multiples, the death of both twins simultaneously, and cases with incomplete outcome data. Maternal and neonatal data were reviewed. Of 46 pregnancies included, in 24 (52%), the dead twin was presenting. Gestational age at delivery was significantly earlier in these cases (mean difference: -5.0 weeks, 95% CI [-7.4, -2.6], p < .001), and emergency cesarean rates were higher 67% versus 32% (OR 4.29, 95% CI [1.25, 14.7], p = .02). There were no differences in the frequency of chorioamnionitis, preterm prelabor rupture of membranes, or placental abruption. Survival rates for co-twins were similar in both groups (presenting 83%; not presenting 91%; OR 0.41, 95% CI [0.07, 2.50], p = .29). The increase in neonatal morbidities was related to prematurity rather than to order. Findings were more common in dichorionic twins. Analysis was limited by a small sample size. If the dead twin is presenting, delivery is likely to occur earlier, with associated morbidity for the survivors. This is especially relevant for dichorionic twin pregnancies.

Chorionic villus sampling in the cell-free DNA aneuploidy screening era: careful selection criteria can maximise the clinical utility of screening and invasive testing.

OBJECTIVES: To quantify the impact of cell-free DNA (cfDNA) screening on chorionic villus sampling (CVS) test indications and outcomes in a tertiary maternity service. METHODS: Retrospective cohort study of all CVS procedures performed for any indication on singleton pregnancies at The Royal Women's Hospital, Melbourne, and at Women's Ultrasound Melbourne, Australia, between August 2008 and February 2015. Karyotypes were classified according to pathogenicity and detectability by standard cfDNA screening panels. RESULTS: A total of 2051 CVS procedures, 25 373 twelve-week scans and 2394 cfDNA tests were performed. The CVS rate per 12-week scan fell from 9.8 to 3.9% following introduction of cfDNA screening. The yield of pathogenic chromosomal anomalies per CVS increased from 12.9 to 25.2%, with 70% of pathogenic results now comprising T21, up from 52%. Sixteen (5.3%) of the pathogenic chromosomal abnormalities identified on CVS would not have been predicted by current cfDNA tests. CONCLUSIONS: There is an evolving tension between improved screening performance for common aneuploidies offered by cfDNA testing, and the increasing diagnostic utility of molecular karyotyping. However, the risk of not identifying pathogenic chromosomal abnormalities is low if cfDNA screening is offered in the absence of a structural fetal anomaly, increased nuchal translucency or relevant family history. © 2017 John Wiley & Sons, Ltd.

Antenatal assessment and postnatal outcome of fetal echogenic lung lesions: a decade's experience at a tertiary referral hospital.

INTRODUCTION: Fetal echogenic lung lesions (ELL) are the commonest pulmonary pathology diagnosed on antenatal sonography, and include congenital pulmonary airway malformations (CPAMs) and bronchopulmonary sequestrations. This study aimed to evaluate the predictive utility of the CPAM volume ratio (CVR) at presentation in a series of fetuses with ELLs at a tertiary Australian referral hospital. MATERIAL AND METHODS: Retrospective cohort study of all pregnancies with a prenatal diagnosis of an isolated fetal echogenic lung lesion managed at the Royal Women's Hospital, Victoria, Australia, between 2005 and 2015. Data were obtained from electronic ultrasound image databases and medical records. RESULTS: Sixty-five cases were included in the final analysis. The mean gestation at presentation was 22 weeks and 6 d, and the mean CVR was 0.66. Hydrops was evident in four cases at presentation, and did not develop subsequently in any other case. Significant perinatal concerns - fetal/neonatal demise, hydrops, requirement for neonatal intubation/ventilation, or surgery in the first year of life - did not occur with or following a CVR at presentation of <0.45. The survival rate at 1 year was 95%. DISCUSSION: The CVR is a potentially useful tool to assess all fetal ELLs, and not just those presumed to be CPAMs. A CVR at presentation of <0.45 was associated with favourable outcomes.