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Purpose: The aim of this study is to evaluate the impact of the utility of maternal cell-free DNA (cfDNA) on the number of chorionic villus sampling (CVS) at a mainland Chinese maternal hospital.Methods: This was a retrospective cohort study conducted in consecutive singleton pregnancies that underwent CVS between the 11th and 14th gestational weeks at a Chinese maternal hospital during a nine-year period. The indications, complications and prenatal diagnosis results were evaluated.Results: This study consisted of 5108 CVS procedures, including 2000 performed for fetal karyotyping, and 3108 performed for fetal single-gene genotyping. During the period with the introduction of cfDNA, the proportion of the number of CVS procedures for the indication of positive serum screening declined significantly, and abnormal ultrasound was the main indication for CVS performed for fetal karyotyping. Thalassemia was always the main indication for CVS, accounting for 50.5% of all CVS cases.Conclusions: cfDNA has changed the spectrum of CVS indications. CVS is now the invasive procedure performed for patients with a fetus having a very high risk of fetal genetic defects, including fetuses having major abnormal ultrasound or having a risk of single-gene disorder inherited from their parents. [ABSTRACT FROM AUTHOR]

Objective: In this study, we report the indications for prenatal cytogenetic diagnosis of triploid cases, in an attempt to identify clues to early diagnosis.Study Design: This was a retrospective analysis of prenatal cases of triploidy during a 9-year period at mainland China. Clinical data were reviewed for these cases, including maternal demographics, indications for invasive testing, fetal ultrasound findings, and pregnancy outcomes.Results: A total of 22 singleton pregnancies affected with triploid fetuses were detected. The fetal karyotype included 69,XXX (72.7%) and 69,XXY (27.3%). Eighteen cases were identified by the first trimester screening program. One case was missed by maternal cell-free DNA testing, but detected by second trimester anatomy scan. Three cases escaped the first trimester screening and were detected by second trimester anatomy scan.Conclusions: The present study demonstrates that most triploid cases can be diagnosed prenatally during the first trimester. The early asymmetrical fetal growth restriction, structural anomalies, and extremely high risk serum screening result for trisomy 21 or 18 should alert the physicians to the investigation of triploidy.Key Message: Ultrasound-based first-trimester screening plays a major role in early diagnosis of fetal triploidy. Future replacement of routine first-trimester screening by cell-DNA testing might miss the chance of early diagnosis and management of triploid pregnancies. [ABSTRACT FROM AUTHOR]

Objective: Only a small number of reports have been made on the prenatal ultrasound findings observed in 1p36 deletion syndrome. We explored prenatal diagnosis of 1p36 deletion by ultrasound as well as chromosomal microarray (CMA), and delineated the fetal presentation of this syndrome.Study Design: This was a retrospective analysis of 10 new prenatal cases of 1p36 deletion identified by CMA at a single Chinese medical center. Clinical data were reviewed for these cases, including maternal demographics, indications for invasive testing, sonographic findings, CMA results and pregnancy outcomes.Results: One case was diagnosed because of a positive cell-free DNA (cfDNA) testing result for terminal 1p deletion, and the remaining nine cases were identified because of an abnormal ultrasound findings, including early miscarriage, structural abnormalities and fetal growth restriction. CMA revealed 1p36 deletions to be terminal in six cases, and interstitial in four cases. Deletion sizes ranged from 1.7 to 42.7 Mb.Conclusions: Prenatal findings such as cardiac malformations, especially Ebstein anomaly, and fetal growth retardation should warrant the diagnosis of 1p36 deletion and invasive genetic testing using CMA. [ABSTRACT FROM AUTHOR]

Objective: To evaluate whether cell-free DNA (cfDNA) testing could replace an invasive procedure in pregnancies with isolated fetal omphalocele.Study design: This was a retrospective study of all pregnancies with sonographically detected fetal omphalocele at three tertiary referral centers between 2012 and 2016. Invasive diagnostic testing was performed for genetic investigations using conventional karyotyping or chromosomal microarray. cfDNA testing was assumed to be offered to patients with isolated fetal omphalocele for screening for common aneuploidies.Results: Invasive genetic testing was performed in a total of 107 pregnancies with a fetal omphalocele. Abnormal karyotype was found in 66% (31/47) of nonisolated omphalocele cases and in 1.7% (1/60) of isolated omphalocele cases. No pathogenic copy number variations (CNVs) were detected in 59 cases with isolated omphalocele and normal karyotype. If cfDNA screening was used in cases with isolated omphalocele, the affected fetus with trisomy 18 would be detected, and no rare chromosomal aberrations or submicroscopic pathogenic CNVs would be missed.Conclusions: cfDNA testing could be recommended for prenatal genetic evaluation in pregnancies with isolated fetal omphalocele after thorough pretest counseling.Key Message: A very low percentage of aneuploidies and rare chromosomal/subchromosomal abnormalities are found in prenatal cases of isolated omphalocele. It seems that for pregnancies with isolated omphalocele, cfDNA testing represents an alternative for patients who choose to continue the pregnancies and are reluctant to undertake invasive diagnostic testing. [ABSTRACT FROM AUTHOR]

Objective: To report the experience with first-trimester prenatal detection of pregnancies complicated by trisomy 18. Study design: Proven cases of trisomy 18 identified between 11 and 14 weeks of gestation were retrospectively reviewed. Information on maternal demographics, prenatal sonographic findings, indications for prenatal diagnosis and chromosomal analysis results was obtained by reviewing medical records. Results: During the 7-year period from January 2011 to December 2017, 89 cases of full trisomy 18 had first-trimester indications for prenatal diagnosis at Guangzhou Women and Children's Medical Center. Eighty-five (95.5%) had abnormal sonographic findings in the first trimester. The most common finding was increased nuchal translucency (55.1%), followed by cystic hygroma (18.0%), omphalocele (14.6%), and fetalis hydrops (11.2%). Four cases (4.5%) were not associated with any abnormal first-trimester sonographic finding, and were diagnosed because of routine positive screening results for trisomy 18. A single case was diagnosed because of a positive cell-free DNA (cfDNA) result. Conclusion: These results demonstrate that a large number of fetuses with trisomy 18 have abnormal sonographic findings in the first trimester, and support the continued utility of first-trimester sonographic examination in the diagnosis of this trisomy even with the availability of cfDNA. [ABSTRACT FROM AUTHOR]

Objectives: To study the perinatal outcomes in the women who's the different changes of an increased fetal nuchal translucency thickness. Methods: Since 2013–2016, the pregnant women whose initial measurement of fetal nuchal translucency (NT) ≥ 3.5 mm would be invited to scan the NT again after a week. Between the two measurements over 1 mm, defined as "change". According to different results between two measurements, they were divided into three groups: unchanged group, thinned group and thicken group. To follow-up and compare the perinatal outcomes among the three groups. Results: One hundred seventy-five cases met our criteria and were retrieved in the study. There are 90 cases of the unchanged group, 60 cases of the thinned group and 25 cases of thicken group. Among three groups, the chromosomal abnormalities rate is 11.11, 21.67, and 60.0% respectively, the structure abnormalities rate is 10.0, 8.51, and 20.0%, the normal delivery rate is 76.67, 70.0, and 28.0%. There all have the significantly differences in statistics except the structure abnormalities rate. Conclusion: The chromosomal abnormalities rate and adverse perinatal outcome rate were worse if NT continues to thicken. However, the perinatal outcome of the NT thinned group is no better than the NT unchanged case. [ABSTRACT FROM AUTHOR]

Objectives: To study the perinatal outcomes in the women who's the different changes of an increased fetal nuchal translucency thickness.Methods: Since 2013-2016, the pregnant women whose initial measurement of fetal nuchal translucency (NT) ≥ 3.5 mm would be invited to scan the NT again after a week. Between the two measurements over 1 mm, defined as "change". According to different results between two measurements, they were divided into three groups: unchanged group, thinned group and thicken group. To follow-up and compare the perinatal outcomes among the three groups.Results: One hundred seventy-five cases met our criteria and were retrieved in the study. There are 90 cases of the unchanged group, 60 cases of the thinned group and 25 cases of thicken group. Among three groups, the chromosomal abnormalities rate is 11.11, 21.67, and 60.0% respectively, the structure abnormalities rate is 10.0, 8.51, and 20.0%, the normal delivery rate is 76.67, 70.0, and 28.0%. There all have the significantly differences in statistics except the structure abnormalities rate.Conclusion: The chromosomal abnormalities rate and adverse perinatal outcome rate were worse if NT continues to thicken. However, the perinatal outcome of the NT thinned group is no better than the NT unchanged case. [ABSTRACT FROM AUTHOR]

Objective: To report the experience with first-trimester prenatal detection of pregnancies complicated by trisomy 18.Study design: Proven cases of trisomy 18 identified between 11 and 14 weeks of gestation were retrospectively reviewed. Information on maternal demographics, prenatal sonographic findings, indications for prenatal diagnosis and chromosomal analysis results was obtained by reviewing medical records.Results: During the 7-year period from January 2011 to December 2017, 89 cases of full trisomy 18 had first-trimester indications for prenatal diagnosis at Guangzhou Women and Children's Medical Center. Eighty-five (95.5%) had abnormal sonographic findings in the first trimester. The most common finding was increased nuchal translucency (55.1%), followed by cystic hygroma (18.0%), omphalocele (14.6%), and fetalis hydrops (11.2%). Four cases (4.5%) were not associated with any abnormal first-trimester sonographic finding, and were diagnosed because of routine positive screening results for trisomy 18. A single case was diagnosed because of a positive cell-free DNA (cfDNA) result.Conclusion: These results demonstrate that a large number of fetuses with trisomy 18 have abnormal sonographic findings in the first trimester, and support the continued utility of first-trimester sonographic examination in the diagnosis of this trisomy even with the availability of cfDNA. [ABSTRACT FROM AUTHOR]

Objective: To investigate the ratio of prenasal thickness (PT) to nasal bone length (NBL) in normal and trisomy 21 fetuses in the second and third trimester in Chinese population. Methods: The NBL and PT were measured blindly by using 3D volumes in 143 normal fetuses and 31 trisomy 21 fetuses. Results: The mean PT ( r = 0.83, p = 0.004) and NBL ( r = 0.87, p = 0.0062) both increased with the gestation age, while the PT/NBL ratio ( r = 0.12, p > 0.10) remained stable. There was significant difference between normal and trisomy 21 fetuses ( p < 0.001). If we took the 95th of the normal fetuses as the cut-off value, the detection rate was only 46%. By using ROC curve to evaluate the screening value of PT/NBL ratio, the area under receiver operating characteristic (ROC) curve was 0.88 (95% confidence interval 0.81 to 0.94, p < 0.0001). Conclusions: In Chinese population, the PT/NBL ratio is not a very strong ultrasound marker to predict trisomy 21 fetuses. However, it can be used as an ultrasound marker for Down syndrome screening during the second and third trimester of pregnancy. [ABSTRACT FROM AUTHOR]

Objective: We describe the changes over a 4-year period in the number of diagnostic testing after the introduction of non-invasive prenatal testing (NIPT).Methods: The rate of NIPT as an indication in women who received amniocentesis, and the number of amniocentesis required for detection of one case with major aneuploidy were compared between a 1-year baseline period before the introduction of NIPT, and the 3 years following NIPT introduction.Results: A total of 7536 amniocentesis procedures were performed over the 4-year study period. During the baseline period of the year 2011, the number of invasive testing required for detection of one common trisomy was 57. During the first 2 years that NIPT was offered, NIPT averaged 1.7 percent of the total indications for amniocentesis, and the required number of invasive testing decreased to 30. With the increase of the percentage of NIPT during the 3rd year, the required number of invasive testing further decreased to 26.Conclusion: After the clinical introduction of NIPT, invasive prenatal diagnostic testing had not decreased at a Chinese prenatal diagnostic unit, but a remarkably improved detection rate of major aneuploidies in diagnostic procedures was observed. [ABSTRACT FROM AUTHOR]

Objective: To report the strategy of first-trimester aneuploidy screening in pregnancies at risk for homozygous α(0)-thalassemian.Methods: Women at risk of homozygous α(0)-thalassemia were given an ultrasound examination at 11-14 weeks' gestation to exclude an affected pregnancy. Fetal cardiothoracic ratio (CTR) and nuchal translucence (NT) were measured. If cardiomegaly was found, chorionic villus sampling (CVS) was offered for α-thalassemia; otherwise the first-trimester combined screening test was performed on the pregnancy. The invasive testing for karyotyping was only followed in those cases with a positive aneuploidy screening test.Results: In total, 69 of 288 pregnancies were found to be affected by homozygous α(0)-thalassemia using ultrasound, and the findings were confirmed by invasive testing. In the remaining 219 pregnancies, invasive testing was not performed for α-thalassemia because of a normal fetal CTR, and the women received the first-trimester combined screening. Nine CVS procedures were performed for karyotyping because of a positive aneuploidy screening. Totally three pregnancies with aneuploidy were diagnosed and terminated.Conclusions: Our strategy can selectively detect aneuploidy pregnancies not affected by homozygous α-thalassemia, and, meanwhile, save on the cost of unnecessary aneuploidy screening or karyotyping in pregnancies with an affected fetus of homozygous α(0)-thalassemia. [ABSTRACT FROM AUTHOR]

α-Thalassemia is a common inherited disease in southern China. The severest form is Hb Bart's hydrops fetalis, in which the affected fetuses almost always die in utero or shortly after birth, and the mothers are at high risk for severe morbidity. Therefore, this condition should be controlled, especially prenatally. In this study, we reported on a two-year experience in prenatal control of Hb Bart's hydrops fetalis at a mainland Chinese hospital. Totally, 573 pregnancies at risk for Hb Bart's hydrops fetalis were referred and different prenatal procedures were offered depending on the gestational age at presentation. One hundred fifty-two affected fetuses were diagnosed prenatally; among these, only half presented in early gestation, and were terminated in time. Although our prenatal program has successfully prevented the birth of children with severe thalassemia, it does not show a satisfactory outcome, considering the gestational age when an affected pregnancy is terminated. [ABSTRACT FROM AUTHOR]