First Trimester Ultrasound in Prenatal Diagnosis-Part of the Turning Pyramid of Prenatal Care

Sonographic measurement of ear length among normal fetuses of pregnant Igbo women in port Harcourt, Nigeria

BACKGROUND

Fetal ear length measurement has been associated with some clinical values: sonographic marker for chromosomal aneuploidy and for biometric estimation of fetal gestational age.

OBJECTIVES

To establish a baseline reference value for fetal ear length and to assess relationship between fetal ear length and gestational age.

METHODS

Ear length measurements were obtained prospectively from fetuses in 551 normal singleton pregnancies of 15 to 41 weeks gestation. Normal cases were defined as normal sonographic findings during examination plus normal infant post-delivery. The relationship between gestational age (GA) in weeks and fetal ear length (FEL) in millimeters were analyzed by simple linear regression. Correlation of FEL measurements with GA, biparietal diameter (BPD), Head circumference (HC), Abdominal Circumference (AC), Femur Length (FL) and maternal age (MA) were also obtained.

RESULTS

Linear relationships were found between FEL and GA (FEL=0.872GA-2.972). There was a high correlation between FEL and GA (r = 0.837; P = .001). Good linear relationship and strong positive correlation were demonstrated between FEL and BPD, AC, HC, and FL (p<0.05).

CONCLUSION

The result of this study provides normal baseline reference value for FEL. The study also showed good linear relationship and good correlation between FEL and fetal biometric measurements.

Microarray and RASopathy-disorder testing in fetuses with increased nuchal translucency

OBJECTIVES

To determine the incidence of chromosomal abnormalities, submicroscopic chromosomal abnormalities and RASopathy-disorder (RD) pathogenic variants in a cohort of pregnancies with nuchal translucency thickness (NT) ≥ 3.5 mm, and to propose a clinical protocol for surveillance of this group of patients.

METHODS

This was a retrospective chart review of patients referred to The Prenatal Diagnosis and Medical Genetics Program at Mount Sinai Hospital between January 2013 and December 2015, due to NT ≥ 3.5 mm, who underwent chorionic villus sampling or amniocentesis. Patients underwent extensive genetic counseling prior to invasive procedures and testing. Quantitative fluorescence polymerase chain reaction (QF-PCR) was performed as the first-line test for aneuploidy. If the result was negative, patients underwent karyotyping and/or chromosomal microarray analysis (CMA), and if the findings were normal, they had testing for RD pathogenic variants, which included nine known genes. Patients also underwent detailed fetal ultrasound examinations and echocardiography, performed by expert operators.

RESULTS

A total of 226 eligible patients were identified. In 116/226 (51.3%) patients, QF-PCR identified a chromosomal aneuploidy. The remaining 110/226 (48.7%) patients had further genetic testing. Karyotyping/CMA detected an abnormal/pathogenic cytogenetic result in 9/110 (8.2%) patients, as well as five variants of unknown significance (VOUS). RD testing yielded three pathogenic variants (3/103), giving a detection rate of 2.9%, and one VOUS. The optimal NT cut-off for RD screening was 7.9 mm in this population. In 92/110 (83.6%) patients, the genetic investigations were normal. Of these pregnancies, an early (14-16 weeks' gestation) detailed fetal ultrasound examination identified a structural abnormality in 24 (26.1%), 15 (16.3%) had an abnormal detailed ultrasound examination at 18-22 weeks' gestation and fetal echocardiography showed a cardiac abnormality in nine (9.8%). The birth outcome in the 83 pregnancies that had normal genetic investigations and known outcome included seven (8.4%) cases of termination of pregnancy, seven (8.4%) cases of intrauterine fetal death and 69 (83.1%) cases of live birth. Nine (9.8%) patients were lost to follow-up.

CONCLUSIONS

Both CMA and molecular testing for RD are important investigations in pregnancies with NT ≥ 3.5 mm. The use of genetic testing combined with fetal ultrasound examination provides valuable information that can influence pregnancy outcome, and provide recurrence risks, in this patient population. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Chromosomal microarray analysis for the detection of chromosome abnormalities in fetuses with echogenic intracardiac focus in women without high-risk factors

To investigate the association between pathogenic copy number variants (p-CNVs) and abnormal karyotypes detected by chromosomal microarray analysis (CMA) and echogenic intracardiac focus (EIF).This was a retrospective study of fetuses with EIF with CMA data at the Prenatal Diagnosis Center of the West China Second University Hospital of Sichuan University between September 2014 and May 2017. Fetuses were assigned to the isolated EIF and non-isolated EIF groups according to the presence of other ultrasound abnormalities.Among 244 pregnant women, there were 143 cases of isolated EIF and 101 of non-isolated EIF. CMA revealed chromosome abnormality (n = 9 (3.7%): trisomy 21, n = 4; sexual trisomy, n = 2; and p-CNV, n = 3), variants of unknown significance (VOUS, n = 19), and benign CNV (b-CNV, n = 216). Among the fetuses with isolated EIF, 5 had chromosomal abnormalities (3.5%). Among the fetuses with non-isolated EIF, four had chromosomal abnormalities (4.0%). All fetuses with trisomy 21 were in the non-isolated group. The frequency of labor induction was 66.7% (6/9) among the fetuses with chromosome abnormality and 21.1% (4/19) among those with VOUS. Among those with chromosomal abnormalities, one (11.1%) had congenital heart disease.In pregnant women without high-risk factors for chromosomal abnormalities, ultrasound abnormalities, including EIF, could be an indication for CMA. Ultrasound abnormalities (including EIF) and chromosome abnormality could indicate a high risk of CHD. The presence of EIF and at least another ultrasound abnormality could indicate a high risk of trisomy 21.

Risk Assessment at 11-14-Week Antenatal Visit: A Tertiary Referral Center Experience from South India

Background

Present study carried out in a tertiary referral hospital in South India attempts to determine the predictive value of integrated screening at 11-14-week antenatal visit.

Objectives

To determine the detection rate of fetal abnormalities at 11-14 weeks and also to predict the placental dysfunction disorders based on early integrated evaluation.

Method

Integrated screening performed on 440 women between 11 and 14 weeks, including detailed maternal history [medical history, bad obstetric history (BOH)], body mass index (BMI), mean arterial pressure (MAP), detailed ultrasound and maternal serum biochemistry as part of combined first-trimester screening for aneuploidy.

Results

There were two proven Down's syndrome foetuses; both detected with combined screening test. There were 12 fetuses with major anomalies, out of whom 7 (58.3%) detected in 11-14-week scan. Among 440, 114 pregnancies (25.9%) developed complications in pregnancy, including 33 (7.5%) gestational hypertension, 8 (1.8%) pre-eclampsia, 41 (9.38%) SGA, 13 (2.9%) abortions, 22 (5%) indicated and 9 (2.04%) spontaneous preterm deliveries, 38 (8.63%) GDM and 3 (0.6%) stillbirth/IUD. Among the risk factors, age >35 years, BMI >23 kg/m², BOH, MAP >105 mmHg and PAPP-A <0.5 MoM correlated well with adverse outcome. Using early integrated screening, 78.9% of obstetric complications could be predicted although 306 (69.5%) were labeled high risk, among whom 90 (29.4%) developed adverse pregnancy outcomes.

Conclusions

Majority of fetal abnormalities can be detected, and majority adverse pregnancy outcomes can be predicted at 11-14-week antenatal visit, although this study shows high screen positivity and low specificity in a tertiary referral unit.