PURPOSE: This study aimed to investigate fetal ultrasonographic findings in cases of prenatally diagnosed de novo balanced translocations and the role of fetal ultrasound in prenatal genetic counseling. MATERIALS AND METHODS: We collected cases with de novo balanced translocations that were confirmed in chorionic villus sampling, amniocentesis, and cordocentesis between 1995 and 2016. A detailed, high-resolution ultrasonography was performed for prediction of prognosis. Chromosomes from the parents of affected fetuses were also analyzed to determine whether the balanced translocations were de novo or inherited. RESULTS: Among 32,070 cases with prenatal cytogenetic analysis, 27 cases (1/1,188 incidence) with de novo balanced translocations were identified. Fourteen cases (51.9%) showed abnormal findings, and the frequency of major structural anomalies was 11.1%. Excluding the major structural anomalies, all mothers who continued pregnancies delivered healthy babies. CONCLUSION: Results of a detailed, high-resolution ultrasound examination are very important in genetic counseling for prenatally diagnosed de novo balanced translocations.
Amniocentesis ; Chorionic Villi Sampling ; Cordocentesis ; Cytogenetic Analysis ; Female ; Fetus ; Genetic Counseling ; Humans ; Mothers ; Parents ; Pregnancy ; Prenatal Diagnosis ; Prognosis ; Translocation, Genetic ; Ultrasonography* ; Ultrasonography, Prenatal

Partial hydatidiform mole and coexisting fetus is a rare entity with antecedent high risk of maternal and fetal complications, and risk of persistent trophoblastic disease in later life. Here, we report a case of twin pregnancy with live fetus identified as 45,X and normal placenta and another partial mole. Ultrasound scan at 10 weeks showed a hydrops fetus with a focal area of multicystic placenta. The patient underwent chorionic villus sampling and amniocentesis for chromosomal analysis, and the result was 45,X. Based on these finding, the patient then underwent induced abortion. Pathological examination (immunohistochemical staining) of the placenta confirmed the partial mole. This report suggests that careful prenatal ultrasonography and appropriate karyotyping in a molar pregnancy and coexisting fetus enable early diagnosis and may be beneficial for prognosis.
Abortion, Induced ; Amniocentesis ; Chorionic Villi Sampling ; Early Diagnosis ; Edema ; Female ; Fetus* ; Humans ; Hydatidiform Mole* ; Karyotyping ; Molar* ; Placenta ; Pregnancy ; Pregnancy, Twin ; Prognosis ; Trophoblasts ; Turner Syndrome* ; Twins ; Ultrasonography ; Ultrasonography, Prenatal

Although conventional prenatal screening tests for Down syndrome have been developed over the past 20 years, the positive predictive value of these tests is around 5%. Through these tests, many pregnant women have taken invasive tests including chorionic villi sampling and amniocentesis for confirming Down syndrome. Invasive test carries the risk of fetal loss at a low but significant rate. There is a large amount of evidence that non-invasive prenatal test (NIPT) using cell free DNA in maternal serum is more sensitive and specific than conventional maternal serum and/or ultrasound screening. Therefore implementing NIPT will increase aneuploidy detection rate and concurrently decrease fetal loss rate accompanying invasive test. More than 1,000,000 NIPT were performed globally since 2011. The uptake rate of NIPT is expected to increase more rapidly in the future. Moreover, as a molecular genetic technique advances, NIPT can be used for not only common aneuploidy screening but single gene disorder, microdeletion, and whole fetal genome sequencing. In this review, I will focus on the NIPT for common aneuploidies such as trisomy 13, 18, and 21.
Amniocentesis ; Aneuploidy ; Chorionic Villi Sampling ; DNA* ; Down Syndrome ; Female ; Genome ; Humans ; Mass Screening ; Maternal Serum Screening Tests ; Molecular Biology ; Pregnancy ; Pregnant Women ; Prenatal Diagnosis ; Trisomy ; Ultrasonography

OBJECTIVE: To validate quantitative fluorescent polymerase chain reaction (QF-PCR) via chorionic villus sampling (CVS) for the diagnosis of fetal aneuploidies. METHODS: We retrospectively reviewed the medical records of consecutive pregnant women who had undergone CVS at Cheil General Hospital between December 2009 and June 2014. Only cases with reported QF-PCR before long-term culture (LTC) for conventional cytogenetic analysis were included, and the results of these two methods were compared. RESULTS: A total of 383 pregnant women underwent QF-PCR and LTC via CVS during the study period and 403 CVS specimens were collected. The indications of CVS were as follows: abnormal first-trimester ultrasonographic findings, including increased fetal nuchal translucency (85.1%), advanced maternal age (6.8%), previous history of fetal anomalies (4.2%), and positive dual test results for trisomy 21 (3.9%). The results of QF-PCR via CVS were as follows: 76 (18.9%) cases were identified as trisomy 21 (36 cases), 18 (33 cases), or 13 (seven cases), and 4 (1.0%) cases were suspected to be mosaicism. All results of common autosomal trisomies by QF-PCR were consistent with those of LTC and there were no false-positive findings. Four cases suspected as mosaicism in QF-PCR were confirmed as non-mosaic trisomies of trisomy 21 (one case) or trisomy 18 (three cases) in LTC. CONCLUSION: QF-PCR via CVS has the advantage of rapid prenatal screening at an earlier stage of pregnancy for common chromosomal trisomies and thus can reduce the anxiety of parents. In particular, it can be helpful for pregnant women with increased fetal nuchal translucency or abnormal first-trimester ultrasonographic findings.
Aneuploidy* ; Anxiety ; Chorion* ; Chorionic Villi Sampling* ; Chorionic Villi* ; Cytogenetic Analysis ; Diagnosis ; Down Syndrome ; Female ; Fluorescence ; Hospitals, General ; Humans ; Maternal Age ; Medical Records ; Mosaicism ; Nuchal Translucency Measurement ; Parents ; Polymerase Chain Reaction* ; Pregnancy ; Pregnant Women ; Prenatal Diagnosis* ; Retrospective Studies ; Trisomy

A 31-year-old woman, who was pregnant with twins, underwent chorionic villus sampling because of increased nuchal translucency in one of the fetuses. Cytogenetic analysis showed a normal karyotype in the fetus with increased nuchal translucency. However, the other fetus, with normal nuchal translucency, had a derivative X chromosome (der(X)). For further analysis, fluorescence in situ hybridization (FISH) and additional molecular studies including fragile X analysis were performed. FISH analysis confirmed that the Y chromosome was the origin of extra segment of the der(X). The X-chromosome breakpoint was determined to be at Xq27 by FMR1 CGG repeat analysis, and the Y-chromosome breakpoint was determined to be at Yq11.23 by the Y chromosome microdeletion study. To predict the fetal outcome, the X-inactivation pattern was examined, and it revealed non-random X inactivation of the der(X). To the best of our knowledge, the identification of an unbalanced Xq;Yq translocation at prenatal diagnosis has never been reported. This study was performed to identify precise breakpoints and the X-inactivation pattern as well as to provide the parents with appropriate genetic counseling.
Adult ; Chorionic Villi Sampling ; Cytogenetic Analysis ; Female ; Fetus* ; Fluorescence ; Genetic Counseling ; Humans ; In Situ Hybridization ; Karyotype ; Nuchal Translucency Measurement ; Parents ; Pregnancy ; Prenatal Diagnosis ; Twins ; X Chromosome ; X Chromosome Inactivation ; Y Chromosome

Recently, noninvasive prenatal test (NIPT) has been adopted as a primary screening tool for fetal chromosomal aneuploidy. The principle of NIPT lies in isolating the fetal fraction of cell-free DNA in maternal plasma and analyzing it with bioinformatic tools to measure the amount of gene from the target chromosome, such as chromosomes 21, 18, and 13. NIPT will contribute to decreasing the need for unnecessary invasive procedures, including amniocentesis and chorionic villi sampling, for confirming fetal aneuploidy because of its higher positive predictive value than that of the conventional prenatal screening method. However, its greater cost than that of the current antenatal screening protocol may be an obstacle to the adoption of this innovative technique in clinical practice. Digital polymerase chain reaction (dPCR) is a novel approach for detecting and quantifying nucleic acid. dPCR provides real-time diagnostic advantages with higher sensitivity, accuracy, and absolute quantification than conventional quantitative PCR. Since the groundbreaking discovery that fetal cell-free nucleic acid exists in maternal plasma was reported, dPCR has been used for the quantification of fetal DNA and for screening for fetal aneuploidy. It has been suggested that dPCR will decrease the cost by targeting specific sequences in the target chromosome, and dPCR-based noninvasive testing will facilitate progress toward the implementation of a noninvasive approach for screening for trisomy 21, 18, and 13. In this review, we highlight the principle of dPCR and discuss its future implications in clinical practice.
Amniocentesis ; Aneuploidy ; Chorionic Villi Sampling ; Chromosome Aberrations ; DNA ; Down Syndrome ; Female ; Mass Screening ; Plasma ; Polymerase Chain Reaction* ; Pregnancy ; Prenatal Diagnosis

No abstract available.
Chorion* ; Chorionic Villi Sampling* ; Chorionic Villi* ; Female ; Fetus* ; Pregnancy ; Prenatal Diagnosis* ; Trisomy*

No abstract available.
Chorion* ; Chorionic Villi Sampling* ; Chorionic Villi* ; Chromosome Aberrations* ; Female ; Pregnancy ; Prenatal Diagnosis*

Since the existence of cell-free fetal DNA (cff-DNA) in maternal circulation was discovered, it has been identified as a promising source of fetal genetic material in the development of reliable methods for non-invasive prenatal diagnosis (NIPD) of fetal trisomy 21 (T21). Currently, a prenatal diagnosis of fetal T21 is achieved through invasive techniques, such as chorionic villus sampling or amniocentesis. However, such invasive diagnostic tests are expensive, require expert technicians, and have a miscarriage risk approximately 1%. Therefore, NIPD using cff-DNA in the detection of fetal T21 is significant in prenatal care. Recently, the application of new techniques using single-molecular counting methods and the development of fetal-specific epigenetic markers has opened up new possibilities in the NIPD of fetal T21 using cff-DNA. These new technologies will facilitate safer, more sensitive and accurate prenatal tests in the near future. In this review, we investigate the recent methods for the NIPD of fetal T21 and discuss their implications in future clinical practice.
Abortion, Spontaneous ; Amniocentesis ; Chorionic Villi Sampling ; Diagnostic Tests, Routine ; DNA ; Down Syndrome ; Epigenomics ; Female ; Humans ; Pregnancy ; Prenatal Care ; Prenatal Diagnosis ; Trisomy

OBJECTIVE: The aims of this study were 1) to evaluate the indications of chorionic villus sampling CVS) and the positive predictive value for fetal chromosomal abnormalities, 2) to evaluate the reliability of CVS at Asan Medical Center, 3) to find out the risk factors of procedure-related fetal loss, 4) to find out the risk factors of culture failure, and 5) to compare transabdominal with transvaginal approaches. METHODS: Medical records of the 429 out of 461 patients in whom the CVS for prenatal cytogenetic diagnosis were performed were reviewed retrospectively for the period of June 1998 to June 2006. RESULTS: (1) The most common indications of CVS were abnormal ultrasonic findings including increased nuchal translucency (153/429, 35.7%), a previous history of cytogenetically abnormal baby (125/429, 29.1%), old maternal age (100/429, 23.3%), family history of genetic disease (22/429, 5.1 %), and parental abnormal karyotype (11/429, 2.6%). (2) The positive predictive value of abnormal karyotyping according to the indication of CVS was highest in the cases showing abnormal USG findings, including increased fetal nuchal translucency (28.3%). (3) The trial success rate of CVS was 99.5%(427/429). Culture failure rate was 1.9%.(4) Of the 427 cases, normal karyotype was revealed in 349 cases (81.7%), abnormal karyotype in 66 cases (15.2%), maternal cell contamination in 6 cases (1.4%), and pseudomosaicism and confined placental mosaicism (CPM) in 6 cases (1.4%). (5) Procedure-related fetal loss rate was 1.6% (7/419). (6) The significant risk factor of fetal loss was presence of preprocedure vaginal bleeding. (7) The significant risk factor of culture failure was a small amount (less than 10 mg) of tissue. (8) The gestational age at procedure was significantly different between transabdominal and transvaginal methods. In the transabdominal approach group, the incidence of fundal location of placenta was significantly more common. CONCLUSION: If CVS is performed by an expert operator and at a good quality of genetic laboratory, CVS is a very safe and reliable procedure for prenatal genetic diagnosis.
Abnormal Karyotype ; Chorion ; Chorionic Villi ; Chorionic Villi Sampling ; Chromosome Aberrations ; Cytogenetics ; Female ; Gestational Age ; Humans ; Incidence ; Karyotype ; Karyotyping ; Maternal Age ; Medical Records ; Mosaicism ; Nuchal Translucency Measurement ; Parents ; Placenta ; Pregnancy ; Pregnancy Trimester, First ; Prenatal Diagnosis ; Retrospective Studies ; Risk Factors ; Ultrasonics ; Uterine Hemorrhage