A Fetus with Congenital Microcephaly, Microphthalmia and Cataract Was Detected with Biallelic Variants in the OCLN Gene: A Case Report.

Microcephaly and microphthalmia are both rare congenital abnormalities, while concurrently, these two are even rarer. The underlying etiology would be complex interplaying between heterogeneous genetic background and the environmental pathogens, particularly during critical periods of early tissue development. Here, we reported a prenatal case with microcephaly, microphthalmia, and bilateral cataracts detected by ultrasonography and confirmed by autopsy. Various routine infection-related tests and invasive genetic testing were negative. Whole genome sequencing of fetus and parents revealed OCLN gene defects may be associated with these multiple congenital abnormalities.

Clinical Implementation of Expanded Carrier Screening in Pregnant Women at Early Gestational Weeks: A Chinese Cohort Study.

Demands for expanded carrier screening (ECS) are growing and ECS is becoming an important part of obstetrics practice and reproductive planning. The aim of this study is to evaluate the feasibility of a small-size ECS panel in clinical implementation and investigate Chinese couples' attitudes towards ECS. An ECS panel containing 11 recessive conditions was offered to Chinese pregnant women below 16 gestational weeks. Sequential testing of their partners was recommended for women with a positive carrier status. The reproductive decision and pregnancy outcome were surveyed for at-risk couples. A total of 1321 women performed ECS successfully and the overall carrier rate was 19.23%. The estimated at-risk couple rate was 0.83%. Sequential testing was performed in less than half of male partners. Eight at-risk couples were identified and four of them performed prenatal diagnosis. Our study demonstrated that a small-size ECS panel could yield comparable clinical value to a larger-size panel when the carrier rate of the individual condition is equal or greater than 1%. In addition, more than half of male partners whose wives were carriers declined any types of sequential testing possibly due to a lack of awareness and knowledge of genetic disorders. Genetic education is warranted for the better implementation of ECS.

The utility of genome-wide cell-free DNA screening in the prenatal diagnosis of Pallister-Killian syndrome.

OBJECTIVE: To report genome-wide cell-free DNA (cfDNA) screening facilitating the diagnosis of Pallister-Killian syndrome (PKS). METHODS: This is a retrospective cohort analysis of positive genome-wide cfDNA screening results showing increased signal from chromosome 12 and the detection of PKS. The genome-wide cfDNA screening results and the subsequent investigations were reviewed. RESULTS: Three singleton pregnancies (3/29007) from 2016 to 2017 yielded positive results indicating large gains on the entire p-arm of chromosome 12. In two cases, multiple structural abnormalities were detected by prenatal ultrasound and the couples opted for termination of pregnancy. Chromosomal microarray performed on fetal skin tissues of the two abortuses detected mosaic tetrasomy 12p, consistent with PKS. In the third case, karyotype and chromosomal microarray performed on an amniotic fluid sample also showed mosaic tetrasomy 12p. In each of the three cases, genome-wide cfDNA screening revealed a large gain on chromosome 12p; subsequent prenatal or postnatal diagnostic testing confirmed the diagnosis of PKS. CONCLUSION: We report the ability of genome-wide cfDNA screening to provide early suspicion and facilitate the subsequent genetic diagnosis of PKS. As genome-wide cfDNA screening becomes increasingly available, incidental diagnosis of partial aneuploidies is expected to increase.

Cervical pessary placement for prevention of preterm birth in unselected twin pregnancies: a randomized controlled trial.

BACKGROUND: Preterm birth is the leading cause of neonatal death and handicap in survivors. Although twins are found in 1.5% of pregnancies they account for about 25% of preterm births. Randomized controlled trials in singleton pregnancies reported that the prophylactic use of progestogens, cervical cerclage and cervical pessary reduce significantly the rate of early preterm birth. In twin pregnancies, progestogens and cervical cerclage have been shown to be ineffective in reducing preterm birth. OBJECTIVE: The objective of this study was to test the hypothesis that the insertion of a cervical pessary in twin pregnancies would reduce the rate of spontaneous early preterm birth. STUDY DESIGN: This was a multicenter, randomized controlled trial in unselected twin pregnancies of cervical pessary placement from 20(+0)-24(+6) weeks' gestation until elective removal or delivery vs. expectant management. Primary outcome was spontaneous birth <34 weeks. Secondary outcomes included perinatal death and a composite of adverse neonatal outcomes (intraventricular haemorrhage, respiratory distress syndrome, retinopathy of prematurity or necrotizing enterocolitis) or need for neonatal therapy (ventilation, phototherapy, treatment for proven or suspected sepsis, or blood transfusion). Analysis was by intention to treat. This trial is registered in the ISRCTN registry, number 01096902. RESULTS: A total of 1,180 (56.0%) of the 2,107 eligible women agreed to take part in the trial; 590 received cervical pessary and 590 had expectant management. Two of the former and one of the latter were lost to follow up. There were no significant differences between the pessary and control groups in rates of spontaneous birth <34 weeks (13.6% vs. 12.9%; relative risk 1.054, 95% confidence interval [CI] 0.787-1.413; p=0.722), perinatal death (2.5% vs. 2.7%; relative risk 0.908, 95% CI 0.553-1.491; p=0.702), adverse neonatal outcome (10.0 vs. 9.2%; relative risk 1.094, 95% CI 0.851-1.407; p=0.524) or neonatal therapy (17.9% vs. 17.2%; relative risk 1.040, 95% CI 0.871-1.242; p=0.701). A post hoc subgroup analysis of 214 women with short cervix (≤25 mm) showed no benefit from the insertion of a cervical pessary. CONCLUSION: In women with twin pregnancy, routine treatment with cervical pessary does not reduce the rate of spontaneous early preterm birth.

Pseudoamniotic Band Syndrome after In Utero Intervention for Twin-to-Twin Transfusion Syndrome: Case Reports and Literature Review.

Pseudoamniotic band syndrome (PABS) is a rare iatrogenic complication that arises after invasive procedures in monochorionic twins. We report 3 cases of PABS, 2 after fetoscopic laser photocoagulation and 1 after bipolar cord coagulation. Two cases were detected antenatally by ultrasound; out of the two, one underwent successful fetoscopic release of amniotic band, which is the first report in twin pregnancy to our knowledge. In our centre, the incidence of PABS was found to be 2%. There were 25 cases of PABS reported previously, of which 12 cases with clinical details were reviewed together with our 3 cases. The fetal limbs were involved in all 15 cases, leading to constriction or amputation. The umbilical cord was involved in 2 cases, resulting in fetal death in one and pregnancy termination in the other. Antenatal detection of PABS is rare (27%; 4/15) as this requires a high index of suspicion. Serial postoperative targeted ultrasound surveillance of the fetal limbs and umbilical cord is necessary, particularly when features of septostomy or chorioamniotic membrane separation are found. Colour Doppler examination for the perfusion of the affected limb should be performed when PABS is detected. Fetoscopic release of amniotic band could salvage the fetal limb from amputation when impaired blood flow is detected.

Noninvasive prenatal testing of trisomies 21 and 18 by massively parallel sequencing of maternal plasma DNA in twin pregnancies.

OBJECTIVE: The objective of this study is to assess the performance of noninvasive prenatal testing for trisomies 21 and 18 on the basis of massively parallel sequencing of cell-free DNA from maternal plasma in twin pregnancies. METHOD: A double-blind study was performed over 12 months. A total of 189 pregnant women carrying twins were recruited from seven hospitals. Maternal plasma DNA sequencing was performed to detect trisomies 21 and 18. The fetal karyotype was used as gold standard to estimate the sensitivity and specificity of sequencing-based noninvasive prenatal test. RESULTS: There were nine cases of trisomy 21 and two cases of trisomy 18 confirmed by karyotyping. Plasma DNA sequencing correctly identified nine cases of trisomy 21 and one case of trisomy 18. The discordant case of trisomy 18 was an unusual case of monozygotic twin with discordant fetal karyotype (one normal and the other trisomy 18). The sensitivity and specificity of maternal plasma DNA sequencing for fetal trisomy 21 were both 100% and for fetal trisomy 18 were 50% and 100%, respectively. CONCLUSION: Our study further supported that sequencing-based noninvasive prenatal testing of trisomy 21 in twin pregnancies could be achieved with a high accuracy, which could effectively avoid almost 95% of invasive prenatal diagnosis procedures.

Radiofrequency ablation for selective reduction in complicated monochorionic multiple pregnancies.

OBJECTIVE: To evaluate the perinatal outcome of monochorionic (MC) multiple pregnancies after selective reduction by radiofrequency ablation (RFA). METHODS: A case series of all MC multiple pregnancies with selective reduction by RFA in one single institution was reviewed. RESULTS: Ten consecutive patients with an MC pregnancy (9 pairs of twins and 1 set of triplets) underwent RFA. The median gestational age at the time of the procedure was 15.6 weeks (range, 12.3-19.6). The indications for selective reduction included discordance for fetal anomalies (4 cases), twin reversed arterial perfusion sequence (3 cases), selective intrauterine growth restriction (2 cases) and severe twin-twin transfusion syndrome (1 case). All procedures were technically successful in achieving selective reduction. The overall survival rate of the co-twin was 81.8% (9/11), and the median gestational age at delivery was 35.9 weeks (range, 32.4-38.6). There was one preterm delivery before 34 weeks of gestation (11.1%). Preterm premature rupture of the membranes occurred in 2 patients (20%); however, this was not observed within 4 weeks postoperatively, nor did they deliver before 32 weeks. CONCLUSIONS: RFA is a promising technique for selective reduction in complicated MC multiple pregnancies with a high survival rate and low complication rate.

Secondary findings from non-invasive prenatal testing for common fetal aneuploidies by whole genome sequencing as a clinical service.

OBJECTIVE: To report secondary or additional findings arising from introduction of non-invasive prenatal testing (NIPT) for aneuploidy by whole genome sequencing as a clinical service. METHODS: Five cases with secondary findings were reviewed. RESULTS: In Case 1, NIPT revealed a large duplication in chromosome 18p, which was supported by arrayCGH of amniocyte DNA, with final karyotype showing mosaic tetrasomy 18p. In Case 2, a deletion in the proximal long arm of chromosome 18 of maternal origin was suspected and confirmed by arrayCGH of maternal white cell DNA. In Case 3, NIPT was negative for trisomies 21 and 18. In-depth analysis for deletions/duplications was requested when fetal structural anomalies were detected at routine scan. A deletion in the proximal long arm of chromosome 3 was found and confirmed by karyotyping. In Case 4, NIPT correctly predicted confined placental mosaicism with triple trisomy involving chromosomes X, 7 and 21. In Case 5, NIPT correctly detected a previously unknown maternal mosaicism for 45X. CONCLUSION: Non-invasive prenatal testing is able to detect a wide range of fetal, placental and maternal chromosomal abnormalities. This has important implications on patient counseling when an abnormality is detected by NIPT.

A method for noninvasive detection of fetal large deletions/duplications by low coverage massively parallel sequencing.

OBJECTIVE: To report the feasibility of fetal chromosomal deletion/duplication detection using a novel bioinformatic method of low coverage whole genome sequencing of maternal plasma. METHOD: A practical method Fetal Copy-number Analysis through Maternal Plasma Sequencing (FCAPS), integrated with GC-bias correction, binary segmentation algorithm and dynamic threshold strategy, was developed to detect fetal chromosomal deletions/duplications of >10 Mb by low coverage whole genome sequencing (about 0.08-fold). The sensitivity/specificity of the resultant FCAPS algorithm in detecting deletions/duplications was firstly assessed in silico and then tested in 1311 maternal plasma samples from those with known G-banding karyotyping results of the fetus. RESULTS: Deletions/duplications, ranged from 9.01 to 28.46 Mb, were suspected in four of the 1311 samples, of which three were consistent with the results of fetal karyotyping. In one case, the suspected abnormality was not confirmed by karyotyping, representing a false positive case. No false negative case was observed in the remaining 1307 low-risk samples. The sensitivity and specificity for detection of >10-Mb chromosomal deletions/duplications were100% and 99.92%, respectively. CONCLUSION: Our study demonstrated FCAPS has the potential to detect fetal large deletions/duplications (>10 Mb) with low coverage maternal plasma DNA sequencing currently used for fetal aneuploidy detection.

Detection of the fetal conotruncal anomalies using real-time three-dimensional echocardiography with live xPlane imaging of the fetal ductal arch view.

OBJECTIVE: To evaluate the role of live xPlane imaging of ductal arch view in detection of fetal conotruncal anomalies. METHODS: Two hundred selected singleton pregnancies, including 152 normal cases, 27 conotruncal anomalies and 21 other types of fetal heart abnormalities were enrolled in this observational study. All the cases were scanned to visualize the ductal arch view with live xPlane imaging by a single observer. The detection rate of conotruncal and non-conotruncal anomalies with live xPlane imaging was compared. RESULTS: In using this new method of live xPlane imaging, an abnormal ductal arch view was visualized in 92.6% of fetal conotruncal anomalies, compared with that of non-conotruncal anomalies (23.8%, p < 0.001). CONCLUSION: The ductal arch view can be obtained by live xPlane imaging. This method is relatively simple and feasible, hence may be a useful tool to detect fetal conotruncal anomalies.

Discordant results between fetal karyotyping and non-invasive prenatal testing by maternal plasma sequencing in a case of uniparental disomy 21 due to trisomic rescue.

Uniparental disomy (UPD) is an uncommon chromosome condition, but UPD involving chromosome 21 is rarely reported. We reported here a case who had first trimester screening test for Down syndrome, chorionic villus sampling for fetal karyotyping, quantitative fluorescence polymerase chain reaction (QF-PCR), as well as non-invasive prenatal testing (NIPT) by maternal plasma sequencing. There were discordant results between fetal karyotyping and NIPT due to UPD 21combined with confined placental mosaicism of trisomy 21. This demonstrated that it is possible to detect placental mosaicism by NIPT, but further studies are required to confirm its sensitivity. Therefore, all positive NIPT results must be confirmed by conventional invasive test and karyotyping. QF-PCR has the additional benefit in diagnosing UPD.

Environmental factors in the first trimester and risk of oral-facial clefts in the offspring.

The averaged incidences of nonsyndromal/isolated cleft lip (CL), cleft palate (CP), and cleft lip with cleft palate (CLCP) by each month-of-conception, and managed in our hospital in from 2002 to 2009 were correlated with the reported levels of sunshine, ultraviolet radiation, and ambient nitrogen oxides (nitrogen oxide, nitrogen monoxide, and nitrogen dioxide), sulfur dioxide, and ozone, at the month of, and then at 4 and 8 weeks after, conception. There were 25, 12, and 22 cases each of CL, CP, and CLCP, respectively, totaling 59 cases (1.21 of 1000 births). On regression analysis, sunshine correlated inversely with the isolated CL at (P = .009) 4 weeks (P = .005) and 8 weeks (P = .008) postconception, and with CP (P = .009) and CLCP (P < .001) at 8 weeks postconception, while NOx correlated inversely with CL (P = .018) and NO with CLCP (P = .031), at 8 weeks postconception. Our results suggested that the interaction between sunshine and nitrogen oxides with other factors results in the reported seasonal variation in the incidence of isolated oral-facial clefts.

Non-invasive prenatal screening of fetal Down syndrome by maternal plasma DNA sequencing in twin pregnancies.

Non-invasive prenatal screening for fetal Down syndrome (NIFTY) by maternal plasma sequencing was performed in 12 subjects with twin pregnancies, including 11 with normal fetuses and 1 with discordant fetal Trisomy 21. For every sample, it was processed, sequenced and reported as soon as it was collected as other clinical samples for singleton pregnancies. The NIFTY test was negative in the 11 pregnancies carried normal fetuses, and was positive (high risk) in the case with discordant fetal Trisomy 21. The sensitivity and specificity were both 100%. This small case series suggested the NIFTY as a screening test for fetal Trisomy 21 is feasible in twin pregnancies.

Cerclage pessary for preventing preterm birth in women with a singleton pregnancy and a short cervix at 20 to 24 weeks: a randomized controlled trial.

OBJECTIVE: To determine the effectiveness of cerclage pessary in the prevention of preterm birth in asymptomatic Chinese women with a short cervix at 20 to 24 weeks. METHODS: Low-risk women carrying singleton pregnancies were screened with transvaginal ultrasound, and those with a cervical length <25 mm at 20 to 24 weeks were recruited into a randomized controlled trial, comparing the prophylactic use of cerclage pessary with expectant management. The analysis was by intent-to-treat. The primary outcome measure was preterm delivery before 34 weeks. RESULTS: Among 4438 screened women, 203 women (4.6%) met the inclusion criteria and 108 (58%) consented for the study. A total of 53 and 55 women were allocated to pessary and control groups, respectively. There was no difference in background demographics, including the mean cervical length (19.6 mm versus 20.5 mm) and the mean gestational age at randomization (both 21.9 weeks). Delivery before 34 weeks occurred in 9.4% and 5.5% (p = 0.46) in the pessary and the control groups, respectively. No differences in major side effects were noted between the groups. CONCLUSION: In our population, <5% had a cervical length of less than 25 mm at 20 to 24 weeks' gestation. The prophylactic use of cerclage pessary did not reduce the rate of preterm delivery before 34 weeks.

Can live xPlane imaging of the in-plane view of interventricular septum be used to detect fetal conotruncal anomalies?

OBJECTIVE: To evaluate the feasibility of live xPlane imaging visualizing the in-plane view of IVS in the screening of the fetal conotruncal anomalies. METHOD: One hundred and fifty-two consecutive normal singleton fetuses and forty-eight fetal cardiac defects (27 conotruncal and 21 non-conotruncal cases), were enrolled in this study. The in-plane view of IVS was firstly acquired with live xPlane imaging and then judged whether it is normal or not by one operator. The focus was put on observing the relationship of pulmonary artery and aorta. The comparison between conotruncal and non-conotruncal anomalies in demonstrating the relationship of pulmonary artery and aorta was performed. RESULT: There were 27 cases of conotruncal anomalies enrolled in this study and 19 cases (70.4%) had the abnormal relationship of aorta and pulmonary artery in the in-plane view of IVS. In 21 cases of non-conotruncal CHDs, however, there were only 5 cases (23.8%) had the abnormal relationship in the in-plane view of IVS (p < 0.001). CONCLUSION: Live xPlane imaging of the in-plane view of IVS is feasible to detect the fetal conotruncal anomalies, which may potentially be a useful tool for the non-experienced operators to screen the fetal conotruncal anomalies.

Clinical application of massively parallel sequencing-based prenatal noninvasive fetal trisomy test for trisomies 21 and 18 in 11,105 pregnancies with mixed risk factors.

OBJECTIVE: To report the performance of massively parallel sequencing (MPS) based prenatal noninvasive fetal trisomy test based on cell-free DNA sequencing from maternal plasma in a routine clinical setting in China. METHOD: The MPS-based test was offered as a prenatal screening test for trisomies 21 and 18 to pregnant women in 49 medical centers over 2 years. A total of 11,263 participants were recruited and the MPS-based test was performed in 11,105 pregnancies. Fetal outcome data were obtained after the expected date of confinement. RESULTS: One hundred ninety cases were classified as positive, including 143 cases of trisomy 21 and 47 cases of trisomy 18. With the karyotyping results and the feedback of fetal outcome data, we observed one false positive case of trisomy 21, one false positive case of trisomy 18 and no false negative cases, indicating 100% sensitivity and 99.96% specificity for the detection of trisomies 21 and 18. CONCLUSION: Our large-scale multicenter study proved that the MPS-based test is of high sensitivity and specificity in detecting fetal trisomies 21 and 18. The introduction of this screening test into a routine clinical setting could avoid about 98% of invasive prenatal diagnostic procedures.

[Distribution and normal reference range of fetal nuchal translucency thickness in Kunming pregnant women in the first trimester].

OBJECTIVE: To establish the normal reference range of fetal nuchal translucency (NT) thickness in Kunming Chinese pregnant women in the first trimester. METHODS: The study samples comprised of 1790 Kunming pregnant women who attended antenatal visit in the first trimester in the First Affiliated Hospital of Kunming Medical University. The general information including maternal date of birth, past pregnant history and other related conditions were recorded. The crown rump length (CRL) and NT thickness at 11 - 13(+6) gestational weeks were measured according to guidelines from Fetal Medicine Foundation (FMF). RESULTS: The total 1790 of normal fetuses was recruited for final analysis. The mean and median values of CRL were (59.6 ± 9.2) mm and 58.3 mm, respectively. The mean and median values of NT thickness were (1.7 ± 0.5) mm and 1.7 mm, respectively. While the CRL were at between 45.0 - 54.9 mm, 55.0 - 64.9 mm, 65.0 - 74.9 mm and 75.0 - 84.0 mm, the corresponding values of NT thickness were 1.0 mm, 1.3 mm, 1.5 mm, 1.5 mm at the 5(th) percentile and 2.0 mm, 2.5 mm, 2.7 mm, 2.9 mm at the 95(th) percentile, respectively, and the corresponding medial values of NT thickness were 1.4 mm, 1.7 mm, 2.0 mm, 2.0 mm, respectively. The NT thickness had no relationship with maternal age (P > 0.05). The mean value of NT thickness was (1.8 ± 1.1) mm in male fetuses. The mean value of NT thickness was (1.7 ± 0.6) mm in female fetuses. The NT thickness in male fetuses was significantly thicker than that of females (P = 0.001). CONCLUSION: The present study established a reference range of normal fetal NT thickness corresponding with CRL in early pregnancy with reliable FMF quality control.

[Fetoscopic guided laser occlusion for twin-to-twin transfusion syndrome in 33 cases].

OBJECTIVE: To evaluate the clinical effect of fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) for monochorionic diamniotic twins (MCDA) pregnancies complicated with twin-to-twin transfusion syndrome(TTTS). METHODS: The clinical data of 33 consecutive cases of TTTS from Mainland China, who had FLOC in the Department of Obstetrics and Gynaecology of Prince of Wales Hospital (The Chinese University of Hong Kong) from November 2003 to December 2010, were reviewed and analyzed for peri-operative complications, perinatal outcomes and fetal survival rate. Clinical stage of TTTS was according to the Quintero staging system. RESULTS: (1) Pregnancy characteristics: the mean maternal age was 30; the median gestational age at FLOC was 23(+4) weeks; according to the Quintero staging system, 3 cases were Quintero staging I, 14 cases were Quintero staging II, 7 cases were Quintero staging III and 9 cases were Quintero staging IV. For the 3 stage I cases, FLOC was performed for severe maternal symptoms of polyhyramnios or severe fetal cardiac dysfunction. (2) COMPLICATIONS: intraoperative complications occurred in 5 patients including four uterine bleedings at the puncture site, one placental vascular anastomosis bleeding. Postoperative complications occurred in 6 patients including 2 abortions and 1 intrauterine death within one week after operation, 2 abortions and 1 amniotic band syndrome occurred from two to four weeks after operation. (3) Perinatal outcome and fetal survival rate: the median interval of 33 patients between FLOC and delivery was 9(+4) weeks; the median gestational age at delivery was 31(+6) weeks; the gestation at delivery was less than 24 weeks in 6% (2/33), 24 to 28 weeks in 21% (7/33), 28 to 32 weeks in 18% (6/33), 32 to 37 weeks in 55% (18/33). The mean birth weight of the donor was 1600 g (350 - 2520 g); the mean birth weight of the recipiert was 1930 g (400 - 3040 g). The overall survival rate, the double infant survival rate, the single survival rate and survival rate for at least one twin was 59% (39/66), 52% (17/33), 15% (5/33) and 67% (22/33), respectively. The overall survival rate dropped from 61% (17/28) in Quintero staging II to 9/18 in Quintero staging IV. CONCLUSIONS: FLOC for MCDA complicated with TTTS is associated with an overall survival of about 60%. Major complications are rare. The outcome is not only related to Quintero staging but also the close monitoring and timely termination of pregnancy.

[Combined spectral karyotyping and microarray-based comparative genomic hybridization for the diagnosis of a case with ring chromosome 15].

OBJECTIVE: To assess the value of spectral karyotyping (SKY) combined with microarray-based comparative genomic hybridization (array-CGH) for the diagnosis of complex ring chromosome aberration. METHODS: For an 8-year-old boy featuring growth retardation, G-banding analysis has indicated a 46,XY,r(15)? karyotype, which was delineated by SKY in combination with array-CGH. RESULTS: The ring chromosome has originated from chromosome 15 according to SKY analysis. Position of the breakpoint (15q26.3) and a 594 kb deletion were revealed by array-CGH. CONCLUSION: Molecular cytogenetic technologies are efficient tools for clarifying complex chromosomal abnormality, which has provided a powerful tool for conventional cytogenetic analysis.