Mode of birth in women with low-lying placenta: protocol for a prospective multicentre 1:3 matched case-control study in Italy (the MODEL-PLACENTA study).

INTRODUCTION: The term placenta praevia defines a placenta that lies over the internal os, whereas the term low-lying placenta identifies a placenta that is partially implanted in the lower uterine segment with the inferior placental edge located at 1-20 mm from the internal cervical os (internal-os-distance). The most appropriate mode of birth in women with low-lying placenta is still controversial, with the majority of them undergoing caesarean section. The current project aims to evaluate the rate of vaginal birth and caesarean section in labour due to bleeding by offering a trial of labour to all women with an internal-os-distance >5 mm as assessed by transvaginal sonography in the late third trimester. METHODS AND ANALYSIS: The MODEL-PLACENTA is a prospective, multicentre, 1:3 matched case-control study involving 17 Maternity Units across Lombardy and Emilia-Romagna regions, Italy. The study includes women with a placenta located in the lower uterine segment at the second trimester scan. Women with a normally located placenta will be enrolled as controls. A sample size of 30 women with an internal-os-distance >5 mm at the late third trimester scan is needed at each participating Unit. Since the incidence of low-lying placenta decreases from 2% in the second trimester to 0.4% at the end of pregnancy, 150 women should be recruited at each centre at the second trimester scan. A vaginal birth rate ≥60% in women with an internal-os-distance >5 mm will be considered appropriate to start routinely admitting to labour these women. ETHICS AND DISSEMINATION: Ethical approval for the study was given by the Brianza Ethics Committee (No 3157, 2019). Written informed consent will be obtained from study participants. Results will be disseminated by publication in peer-reviewed journals and presentation in international conferences. TRIAL REGISTRATION NUMBER: NCT04827433 (pre-results stage).

Isolated Upward Rotation of the Fetal Cerebellar Vermis (Blake's Pouch Cyst) Is a Normal Variant: An Analysis of 111 Cases.

INTRODUCTION: The objective of the study was to provide more detailed data about fetal isolated upward rotation of the cerebellar vermis rotation (Blake's pouch cyst) in particular regarding pregnancy outcome. METHODS: This is a retrospective study of all cases of fetal isolated upward rotation of the cerebellar vermis (URCV) diagnosed in 3 referral centers in Italy from January 2009 to November 2019. Whenever possible, prenatal magnetic resonance imaging (MRI) was performed and a fetal karyotype was obtained. A detailed follow-up was obtained by consultation of medical records, interview with the parents, and the pediatricians. RESULTS: Our study population included 111 patients with a prenatal diagnosis of isolated URCV made at a median gestational age of 21 weeks +3 days (interquartile range (IQR) 21 + 0-22 + 2). The median brain stem-vermis (BV) angle was 27° (IQR 24-29°). In 37.9% of the cases, a regression of the finding with restoration of normal anatomy was noted at a follow-up scan or at postnatal checks. A BV angle of 25° or less predicted regression with a probability in excess of 90%. MRI was performed in utero or at birth in 101 patients and always confirmed sonographic diagnosis. Fetal CGH array and/or karyotype was available in 97 cases and was always normal, but in 1 case. A postnatal follow-up was available in 102 infants (mean 7 months, range 0-10 years of age) and documented a normal neurologic development in all the cases. CONCLUSIONS: Isolated URCV is most likely a normal variant of fetal anatomy without clinical consequences, at least at an early follow-up. A BV angle of 25° or less predicts intrauterine regression of the finding, but the outcome is good in all the cases. When a confident sonographic diagnosis is made, MRI is not mandatory. The risk of a chromosomal anomaly in these cases is probably low.

Tetralogy of Fallot and Outlet Ventricular Septal Defect with Anterior Malalignment Detected at Early Fetal Echocardiography.

OBJECTIVES: To examine the evolution of tetralogy of Fallot (TOF) and outlet ventricular septal defect (VSD) with anterior malalignment (am) from the initial diagnosis at early fetal echocardiography through the gestation and to evaluate the impact of the first-trimester scan on the outcome. METHODS: We identified cases of TOF or outlet VSD with am diagnosed before 16 weeks' gestation. For all cases, prenatal data and pregnancy outcomes were evaluated. In continuing pregnancies, the evolution in severity of the disease was assessed. RESULTS: Fifty-one fetuses with TOF or outlet VSD with am were diagnosed at early fetal echocardiography. Parents opted for termination of pregnancy in all 23 cases associated with additional anomalies. In 2 of 28 continuing pregnancies, there was an intrauterine death. In the remaining 26, there was progression in severity in 7 (by 20-22 weeks in 3 cases and during the third trimester in the remaining 4). CONCLUSIONS: TOF and outlet VSD with am diagnosed before 16 weeks' gestation can progress in severity throughout pregnancy in over one-quarter of cases. In addition, a high proportion of cases diagnosed in the first trimester may have associated extracardiac anomalies, with a significant impact on clinical management and on the rate of early termination of pregnancy.

The influence of fetal sex on the antenatal diagnosis of small for gestational age.

OBJECTIVE: We evaluated the influence of fetal sex on the antenatal diagnosis and detection of small for gestational age (SGA). METHODS: The cohort consisted of unselected singleton pregnancies, undergoing routine biometry and cerebroplacental ratio (CPR) assessment at 36 weeks. Locally fitted equations for centiles and Z scores were used. "Ultrasound SGA" was defined as estimated fetal weight (EFW) < 10th centile, "SGA at birth" as birthweight (BW) < 10th centile adjusted for sex. RESULTS: Among 4112 pregnancies, there were 235 female "ultrasound SGA" fetuses and 177 male; (odds ratios (OR) 1.502 (1.223 - 1.845)); the detection rate of SGA at birth was 50.6% and 40.9%, respectively (OR 1.479 (0.980 - 2.228)). In "ultrasound SGA" girls the abdominal circumference growth velocity (ACGV) between 20 and 36 weeks was less frequently in the lowest decile (OR 0.490 (0.320 - 0.750)), with no differences in CPR. CONCLUSIONS: Females are more commonly diagnosed as SGA; those diagnosed may be at less risk than males.

A reference range of fetal abdominal circumference growth velocity between 20 and 36 weeks' gestation.

OBJECTIVE: To create a single equation and reference range for abdominal circumference growth velocity (ACGV) between 20 and 36 weeks in singleton pregnancies. METHOD: Observational study of pregnant women having routine scans for abdominal circumference (AC) at 20 and 36 weeks' gestation. Exclusion criteria were multiple pregnancy, abnormal karyotype, major fetal abnormalities, and absent data on first-trimester dating. Scan image quality and AC measurement reliability were assessed according to INTERGROWTH-21st criteria. Regression models for the AC mean and standard deviation were fitted separately at 20 and 36 weeks, and z scores were calculated. Abdominal circumference growth velocity was defined as the z score difference between 20 and 36 weeks divided by the interval in days and multiplied by 100. RESULTS: The study population included 3334 fetuses. The equation for ACGV is (((AC36  - 53.090 - 1.081*GA36 )/(0.057638*GA36  + 0.622741)) - ((AC20  + 68.349 - 1.571*GA20 )/(0.06265*GA20  - 2.55361)))*100/(GA36  - GA20 ), where AC is expressed in millimeters and GA is gestational age in days. The 3rd, 5th, 10th, 50th, 90th, 95th, and 97th centiles are -1.8997, -1.6785, -1.3091, -0.0069, 1.3255, 1.7279, 1.9973, respectively. CONCLUSION: We have defined ACGV between 20 and 36 weeks, and we have established its reference range. Further studies are needed to evaluate the clinical significance of growth patterns in the tail ends of this distribution.

The three-vessel and trachea view (3VTV) in the first trimester of pregnancy: an additional tool in screening for congenital heart defects (CHD) in an unselected population.

OBJECTIVE: The aim of the study was to evaluate the feasibility of obtaining the three-vessel and trachea view (3VTV) in an unselected population undergoing first trimester screening for aneuploidy, and to investigate its role in the early detection of congenital heart defects (CHD). METHODS: Cardiac examination was performed by expert sonographers. Abnormal findings of 3VTV were classified in three different subgroups: number, size and spatial relationship of the vessels. RESULTS: We enrolled 6350 consecutive singleton pregnancies and included 5343 cases. Examination of 3VTV was feasible in 94% of cases. Fifty-seven (1%) CHD were present in the study period; 24 cases were excluded because parents opted for termination of pregnancy. Of the remaining 33 cases, 25 were suspected at the first trimester and eight were detected only at the mid-trimester. An abnormal 3VTV was suspected in 22 cases, and it was confirmed in 21. Five cases that were erroneously classified in the subgroup of abnormal vessel number were actually characterized by a diminutive size of one of the great arteries. The detection rate for CHD, including 4-CV and 3VTV, was 75.8%. CONCLUSIONS: Our study demonstrates that 3VTV is an easy plane to obtain by expert sonographers in an unselected population during first trimester. Typical suspicions include detection of abnormal number, size or spatial relationship of the vessels. © 2017 John Wiley & Sons, Ltd.

Diagnosis of congenital heart disease by early and second-trimester fetal echocardiography.

OBJECTIVES: The aim of this study was to compare the cardiac findings at 11 to 14 weeks' gestation with the second-trimester findings to evaluate the reliability of first-trimester echocardiography and the possibility of congenital heart disease evolution. METHODS: The database of our fetal medicine unit was searched for all patients who had undergone fetal echocardiography at 11 to 14 and 18 to 22 weeks' gestation from 2005 to 2010. In all of the antenatally suspected cases of congenital heart disease, the diagnosis was established conclusively by postnatal echocardiography, surgery, or autopsy. RESULTS: Among the 870 fetuses included in the study, 802 were considered to have no abnormalities on both examinations. Thirty-six cases had abnormal findings on both examinations, and 32 had discordant findings. Among the 32 discordant findings, 6 cases had a false-positive diagnosis of congenital heart disease on early echocardiography, and 26 had a different diagnosis. In 14 of these 26 cases, the diagnosis was slightly different on the second-trimester examination, or the defect misdiagnosed in the first trimester was a minor one. In 6 of the remaining 12 fetuses, a major congenital heart disease was missed on the early echocardiography. In 6 cases, the congenital heart disease developed or progressed in severity in the second trimester. CONCLUSIONS: First-trimester echocardiography is feasible and seems to allow considerably earlier detection of major congenital heart disease. However, it should be kept in mind that although most forms of heart defects can be diagnosed early in pregnancy, some may develop and become apparent only later in gestation.

Fetal cardiac evaluation at 11-14 weeks by experienced obstetricians in a low-risk population.

OBJECTIVE: The aim of this study was to evaluate the detection rate of congenital heart diseases (CHD) in a low-risk population by performing cardiac evaluation during the first-trimester screening for chromosomal abnormalities. In this context, the role of four-chamber view, tricuspid regurgitation and abnormal ductus venosus flow in the screening for cardiac anomalies in a low-risk population was also investigated. METHOD: The cardiac examination was performed by obstetricians with extensive experience in first- and second-trimester ultrasound (US). Follow-up US evaluations during the second and third trimesters were offered to all patients. In case of abnormal findings during routine assessment, fetal echocardiography was performed by a fetal cardiologist. RESULTS: Among the 4445 fetuses included in the study, 42 CHD were detected (39 diagnosed prenatally and 3 postnatally). In 27 cases, the fetal cardiologist confirmed the type of CHD diagnosed at US screening. In 1 case, the diagnosis was slightly different in the second trimester, and in 3 of the 26 correctly diagnosed in the first-trimester cases, the CHD developed and progressed in severity. A significant association of major CHD and US first-trimester markers was observed. CONCLUSIONS: First-trimester assessment of the fetal heart is feasible in a low-risk population when performed by experienced obstetricians. However, although most types of CHD can be diagnosed early in pregnancy, some may become apparent later in gestation.