Chorionic Villus Sampling Procedures Research Articles

878 Can maternal-fetal medicine fellows safely perform chorionic villus sampling procedures in ongoing pregnancies?

Obtaining hands on experience in chorionic villus sampling (CVS) can be challenging for MFM trainees. Our protocol allows fellows who have met established criteria to perform CVS under direct supervision in consenting patients with fetal cystic hygroma (CH). The objective of this study was to evaluate the safety of CVS procedures performed by fellows in ongoing pregnancies. This is a retrospective cohort study of patients who had CVS performed from 6/2013 – 12/2019 at a single academic medical center for the indication of CH. Data on clinician training level (attending vs. fellow), karyotype results, number of passes, and approach (transcervical vs. transabdominal) were obtained from hospital records. Outcomes at 2-week follow up were also collected (spontaneous loss within 2 weeks, elective termination within 2 weeks, and ongoing pregnancy rates at 2 weeks). Statistics were performed with chi squared analyses to compare procedural data and 2 week outcomes. 406 CVS were performed during the study time period, 92 of which were performed for CH. 90 had 2-week follow up data available and were included in analysis (n=27 by attendings; n=63 by fellows). All 90 had adequate samples for analysis. 4 losses occurred within 2 weeks of CVS; all had abnormal karyotypes. When comparing CVS outcomes by attendings vs. fellows, there was no difference in the proportion of abnormal karyotypes (17/27 (63.0%) vs. 39/63 (61.9%), p=0.92), elective termination rate within 2 weeks (11/27 (40.7%) vs. 23/63 (36.5%), p=0.70), spontaneous loss rate within 2 weeks (2/27 (7.4%) vs. 2/63 (3.2%), p=0.37), procedures requiring >1 pass (1/27 (3.7%) vs. 9/63 (14.3%), p=0.14), or transcervical approach (15/27 (55.6%) vs. 31/63 (49.2%), p = 0.58). There was no difference in 2-week pregnancy loss rate following CVS performed by attendings vs. fellows. CVS may be safely performed by fellows under supervision.

Continued Validation of Ultrasound Guidance Targeting Tasks: Relationship with Procedure Performance

To determine if deliberative practice with novel ultrasound guidance targeting tasks improves simulated procedural skill. In a nonrandomized interventional trial first year medical students practiced the previous described dowel and straw targeting tasks 1 hour a week for 4 weeks (training group) or had no training (controls). Afterward, they each performed a simulated amniocentesis (AMN) and chorionic villus sampling (CVS) procedure. Procedures were scored using a global rating scale (GRS) and compared between groups with Mann-Whitney U tests. Two-way random effects intraclass correlation coefficients for the inter- and intra-rater variability were calculated for each item in both GRS's. The training group (n = 22) had higher scores on several aspects and overall performance of AMN compared to controls (n = 15). There were no differences between groups for CVS. The inter-rater and intra-rater reliability of the GRS's for both AMN and CVS ranged from 0.16 to 0.89 with most values demonstrating good to excellent agreement. This study demonstrates validity evidence in the content and internal structure domains for the AMN and CVS simulators and their accompanying GRS's. Repetitive practice of the targeting tasks improved student performance in simulated AMN, but modifications are needed for it to be relevant to other procedures such as CVS.

Impact of cell-free fetal DNA on early invasive prenatal diagnosis at a Chinese reference maternal medicine center

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.

Validation Studies for Single Circulating Trophoblast Genetic Testing as a Form of Noninvasive Prenatal Diagnosis

It has long been appreciated that genetic analysis of fetal or trophoblast cells in maternal blood could revolutionize prenatal diagnosis. We implemented a protocol for single circulating trophoblast (SCT) testing using positive selection by magnetic-activated cell sorting and single-cell low-coverage whole-genome sequencing to detect fetal aneuploidies and copy-number variants (CNVs) at ∼1 Mb resolution. In 95 validation cases, we identified on average 0.20 putative trophoblasts/mL, of which 55% were of high quality and scorable for both aneuploidy and CNVs. We emphasize the importance of analyzing individual cells because some cells are apoptotic, in S-phase, or otherwise of poor quality. When two or more high-quality trophoblast cells were available for singleton pregnancies, there was complete concordance between all trophoblasts unless there was evidence of confined placental mosaicism. SCT results were highly concordant with available clinical data from chorionic villus sampling (CVS) or amniocentesis procedures. Although determining the exact sensitivity and specificity will require more data, this study further supports the potential for SCT testing to become a diagnostic prenatal test.

Pain perception during transabdominal chorionic villus sampling: a randomized trial comparing topical ethyl chloride anesthetic spray and lidocaine injection

Background: Chorionic villus sampling is an important invasive procedure used for early antenatal genetic testing that can be associated with anxiety and fear of pain. Pain analgesia prior to chorionic villus sampling can be offered with subdermal lidocaine; however, lidocaine injection itself is associated with pain. Our objective was to determine whether administration of topical ethyl chloride anesthetic spray is associated with decreased pain perception during transabdominal chorionic villus sampling compared to 1% lidocaine subdermal injection.Study design: Women undergoing transabdominal chorionic villus sampling from 10 to 13 weeks and 6 days in an outpatient setting were randomized with equal allocation to either 1% lidocaine injection or topical ethyl chloride anesthetic spray prior to the procedure. Women were asked about their pain on a scale of 0–100 prior to, during, and after the procedure. The primary outcome was pain perception during time of transabdominal chorionic villus sampling as measured on a 100-mm visual analog scale. The secondary outcome was pain immediately after procedure.Results: From October 2016 to June 2017, a total of 120 women were enrolled (63 in the lidocaine injection group and 57 in the topical ethyl chloride anesthetic spray group). Baseline demographic characteristics were similar between groups. During the procedure, patients in the topical ethyl chloride arm demonstrated significantly higher pain scores compared to the lidocaine injection group (median score of 50 mm (interquartile range [IQR]: 40–65) versus 50 mm (IQR: 30–60); p = .03). There was no significant difference in pain scores before or after the procedure.Conclusion: During transabdominal chorionic villus sampling procedures, topical ethyl chloride anesthetic spray is associated with a higher distribution of pain scores as compared to 1% lidocaine subdermal injection, which suggests higher levels of pain.Clinical trial registration: This trial is registered with clinicaltrials.gov (NCT03140293). https://clinicaltrials.gov/ct2/show/NCT03140293?term=NCT03140293&rank=1.

A survey of current clinical practice of chorionic villus sampling.

The number of invasive procedures (chorionic villus sampling (CVS) or amniocentesis) for fetal testing is decreasing because of the availability of non-invasive prenatal test (NIPT) leading to a centralisation of prenatal diagnostic services to accredited fetal medicine centres. A new survey was conducted 10years after the previous one to update the current clinical practice among clinicians who regularly perform CVS. Consultants from 32 centres in the United Kingdom were invited to take part in an online survey evaluating: The total number of CVS procedures carried out in the unit in a typical week, the preferred route (transabdominal [TA] vs transcervical [TC]), technique (use of local anaesthetic [LA] and needle technique). Response rate was 96.9%; TA was the preferred route (96.8%) in all centres except one. Single-needle technique is used exclusively in half the centres (51.6%). LA is used by most operators (90.3%) before the procedure. Three centres did not routinely use LA for CVS. Operators across the United Kingdom almost exclusively use the TA route for CVS with single-needle technique in 51.6% of cases. The use of LA prior to CVS is a very common practice in the United Kingdom.

EP02.10: Placental mosaicism and early oligohydramnios: a case report

We present a case of a 34 year-old gravida 3, para 1 with placental mosaicism and early-onset oligohydramnios. Her first child was born at gestational age (GA) 27+4 with an emergency Caesarean section due to severe pre-eclampsia. At the first trimester ultrasound screening (GA 13+0) the risk for Trisomy 21 was risen–1:64, PAPP-A 0,149 MoM, hCG 0,486 MoM. Chorionic villus sampling (CVS) was performed and tetraploidy was found in 85-90% of the sample cells – karyotype 46,XY/92,XXYY. At GA 16+0, amniocentesis was performed to specify the extent of mosaicism. A normal male karyotype 46,XY was attained and confined placental mosaicism was diagnosed. At GA 19+6 oligohydramnios was discovered in ultrasound – deepest vertical pocket (DPV) depth 1cm. No anatomic anomalies or abnormalities in fetal blood flow indices were found. TORCH analyses showed no recently acquired infections. The family was counselled about the possible complications of this pathology (IUGR, pulmonary hypoplasia, limb contractures), they decided not to terminate the pregnancy. At GA 20+6 the first amnioinfusion was performed with 200mL of saline solution, DPV increased to 2,6cm. 5 further amnioinfusions were performed from GA 22+1 to 28+3. After the 3rd procedure a leakage of amniotic fluid occurred. Betamethazone for fetal lung maturation and antibiotic treatment were started. Given the partial rupture of membranes, risk of limb contractures and no further benefit for the maturation of lungs, a delivery by Caesarean section at GA 30+0 was planned. A premature baby, Apgar 8-8, 1276g (25th percentile) was born. Postoperative follow-up was uneventful. The child required ventilation support due to respiratory distress syndrome and developed bronchopulmonary dysplasia (as a result of prematurity). Placental chromosomal mosaicism is a phenomenon occurring in 1–2% of CVS procedures. In 85-90% of cases the mosaicism is confined to the placenta, the remaining instances are true fetal mosaicism. CPM is associated with IUGR, but its connection to isolated oligohydramnios has not been widely studied. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Declining invasive prenatal diagnostic procedures: A comparison of tertiary hospital and national data from 2012 to 2015

In recent years, the superior accuracy of maternal plasma cell-free DNA-based prenatal screening has resulted in >50% national decline in amniocenteses and chorionic villus sampling (CVS), creating new implications for specialist training. To compare the annual figures on amniocenteses and CVS in a tertiary hospital with national population-based trends between 2012 and 2015. Retrospective study examining the amniocentesis and CVS procedures performed in a tertiary hospital between 2012 and 2015. Numbers of procedures, indications for testing, type of test and diagnostic results were analysed. Trends in the annual numbers of procedures were compared to national population-based data from Medicare Benefits Schedule database. The annual numbers of diagnostic procedures in our tertiary centre fell from 267 to 215 over the study period, representing a 19.5% decline. This was significantly smaller than the corresponding national decline of 53.7% for the same period (P<0.0001). In 2015, ultrasound abnormality (including nuchal translucency ≥3.5mm) surpassed high-risk screening results as the most common indication for invasive testing. Thirty percent of procedures performed for an ultrasound abnormality occurred prior to 18weeks gestation. Our tertiary centre experienced a relatively smaller decline in prenatal diagnostic procedures compared with national figures, largely due to an increase in testing for ultrasound abnormalities. Our results demonstrate the increasing contribution of first trimester ultrasound in the detection of fetal abnormalities in the cell-free DNA era and the continued viability of specialist training in invasive procedures.

Chorionic villus sampling in the cell‐free DNA aneuploidy screening era: careful selection criteria can maximise the clinical utility of screening and invasive testing

To quantify the impact of cell-free DNA (cfDNA) screening on chorionic villus sampling (CVS) test indications and outcomes in a tertiary maternity service. Retrospective cohort study of all CVS procedures performed for any indication on singleton pregnancies at The Royal Women's Hospital, Melbourne, and at Women's Ultrasound Melbourne, Australia, between August 2008 and February 2015. Karyotypes were classified according to pathogenicity and detectability by standard cfDNA screening panels. A total of 2051 CVS procedures, 25 373 twelve-week scans and 2394 cfDNA tests were performed. The CVS rate per 12-week scan fell from 9.8 to 3.9% following introduction of cfDNA screening. The yield of pathogenic chromosomal anomalies per CVS increased from 12.9 to 25.2%, with 70% of pathogenic results now comprising T21, up from 52%. Sixteen (5.3%) of the pathogenic chromosomal abnormalities identified on CVS would not have been predicted by current cfDNA tests. There is an evolving tension between improved screening performance for common aneuploidies offered by cfDNA testing, and the increasing diagnostic utility of molecular karyotyping. However, the risk of not identifying pathogenic chromosomal abnormalities is low if cfDNA screening is offered in the absence of a structural fetal anomaly, increased nuchal translucency or relevant family history. © 2017 John Wiley & Sons, Ltd.

How many procedures does it take? Success of a CVS training program for Maternal Fetal Medicine fellows.

To quantify the learning curve for a training program for Maternal Fetal Medicine (MFM) fellows in obtaining successful transvaginal chorionic villus sampling (CVS) results in women with early pregnancy failure (EPF). Retrospective observational cohort study of transvaginal CVS and subsequent manual vacuum aspiration (MVA) performed by MFM fellows. CVS samples were sent for karyotype, and products of conception (POC) were sent if CVS sample did not yield a result. Success was defined as karyotype result on CVS specimen. A total of 130 women with EPF up to 9 weeks of gestation underwent transvaginal CVS and MVA from December 2011 to April 2015. CVS samples were successful in 53 (40.8%) cases, POC were analyzed for karyotype in 68 (52.3%) cases, and maternal decidua was obtained in 9 (6.9%) cases. Nine MFM fellows performed the CVS and MVA procedures. The mean number of procedures per fellow was 14 (5-24). The average success rate of transvaginal CVS sample was 33.3% after the first procedure and 50% at the 14th procedure. One procedure was performed per patient. Success increased over time from 33.3% to 50.0%. Given the gestational age and failed pregnancy status, this is a reasonable success rate for CVS at time of EPF. © 2016 John Wiley & Sons, Ltd.

Revisiting the challenges of training Maternal Fetal Medicine fellows in chorionic villus sampling

More than a decade ago, researchers described a survey of Maternal Fetal Medicine fellows that showed that chorionic villus sampling training was limited for Maternal Fetal Medicine fellows in the United States. Prenatal screening and diagnosis have rapidly evolved since then and include the introduction of noninvasive aneuploidy screening that uses cell-free fetal DNA. Yet, chorionic villus sampling remains the only method available for first-trimester genetic diagnosis. This study evaluated the chorionic villus sampling training of Maternal Fetal Medicine fellows with respect to availability, competency standards, and education methods. In November 2015, an electronic survey was sent to Maternal Fetal Medicine fellows and fellowship directors of accredited Maternal Fetal Medicine fellowship programs in the United States. Fifty-eight percent of fellows (179/310) and 46% of program directors (35/76) responded. Ninety-five percent of Maternal Fetal Medicine fellows think that invasive diagnostic testing is essential to their training; 100% of fellows have amniocentesis training; and 65% have chorionic villus sampling training. The median number of chorionic villus sampling procedures that are expected during a fellowship in those who trained was 10. Eighty-eight percent of fellows and 89% of program directors state that chorionic villus sampling training could be better; 89% of fellows and 97% of directors would like access to simulated models. Barriers to training included lack of patients (71%) and lack of proficient attending supervisors (43%). Since the last survey, >10 years ago, chorionic villus sampling training has declined further. A decrease in the number of procedures that are performed is the leading barrier to this training.

Procedure-Related Fetal Loss following Chorionic Villus Sampling after First-Trimester Aneuploidy Screening

Objective: The aim was to determine the institutional procedure-related fetal loss rate after chorionic villus sampling (CVS) and the factors which may identify pregnancies at increased risk of having a procedure-related loss. Materials and Methods: Pregnancy outcomes were retrieved of all women having a singleton pregnancy and undergoing a CVS procedure between 2004 and 2013 at a university hospital in Hong Kong. The incidence of procedure-related fetal loss due to unintended miscarriages adjusted for the background loss incidence of miscarriages was determined. Multivariate regression was performed to examine the factors contributing to an unintended fetal loss and miscarriage. Results: CVS was performed on 1,906 fetuses. The procedure-related fetal loss rate was 0.17% (95% CI -0.2 to 0.7). After multivariate analysis, a decreased plasma protein-A (PAPP-A) multiple of the median (OR 0.27; 95% CI 0.08-0.98, p = 0.046) was significantly associated with miscarriage in women who did not undergo a CVS. Patient-specific prediction of spontaneous abortion in women who did not undergo CVS was not statistically significant (AUC 0.56; 95% CI 0.49-0.6, p = 0.14). Conclusions: The CVS-related fetal loss rate adjusted for background loss was 0.17%. Pregnancies with reduced PAPP-A carry an increased risk of miscarriage irrespective of whether they had undergone an invasive procedure.

Using fetal cells for prenatal diagnosis: History and recent progress.

The potential to use fetal cells in the mother's circulation during the first or second trimester for prenatal diagnosis was described in 1968, but it has not been possible do develop a routine clinical prenatal test despite extensive commercial and academic research efforts. Early attention focused on the detection of aneuploidy, but more recent technology opens the possibility of high resolution detection of copy number abnormalities and even whole genome or exome sequencing to detect both inherited and de novo mutations. In the interim, cell-free noninvasive prenatal testing NIPT has allowed improved detection of aneuploidy, but this has led to a sharp reduction in the number of amniocentesis and chorionic villus sampling (CVS) procedures, which inevitably implies reduced detection of serious de novo deletion abnormalities. Attention has focused of both fetal nucleated red blood cells (fnRBCs) and trophoblasts. Recent progress presented at meetings, but not yet published, suggests that it will soon be possible to perform genome-wide relatively high resolution detection of deletions and duplications by recovering fetal trophoblasts during the first trimester and analyzing them by whole gene genome amplification followed by copy number analysis using arrays or next generation sequencing. © 2016 Wiley Periodicals, Inc.

National decline in invasive prenatal diagnostic procedures in association with uptake of combined first trimester and cell-free DNA aneuploidy screening.

In late 2012, a new screening test for fetal aneuploidy based on circulating cell-free DNA (cfDNA) became available to Australian women. The introduction of this technology in the United States has led to a reduction in invasive diagnostic procedures. Analysis of the number of amniocentesis and chorionic villus sampling (CVS) procedures performed in Australia from 1994 to 2014 shows that the introduction of cfDNA testing has been associated with the most rapid decline in invasive procedures in the last 20 years. This change has important implications for training in, and maintenance of, the procedural skills of amniocentesis and CVS.

First-trimester combined screening for trisomy 21 in women at risk for α-thalassemia

Objective: To report the strategy of first-trimester aneuploidy screening in pregnancies at risk for homozygous α0-thalassemian.Methods: Women at risk of homozygous α0-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 α0-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 α0-thalassemia.

Uptake of noninvasive prenatal testing at a large academic referral center

Noninvasive prenatal testing (NIPT) is a recently developed risk-assessment technique with high sensitivity and specificity for fetal aneuploidy. The effect NIPT has had on traditional screening and diagnostic testing has not been clearly demonstrated. In this study, NIPT uptake and subsequent changes in the utilization of first-trimester screen (FTS), chorionic villus sampling (CVS), and amniocentesis in a single referral center is reported. Monthly numbers of NIPT (in high-risk patients), FTS, CVS, and amniocentesis were compared between a 35-month baseline period (April 2009 through February 2012) before introduction of NIPT, and the initial 16 months following NIPT introduction divided in 4-month quarters beginning in March 2012 through June 2013. A total of 1265 NIPT, 6637 FTS, 251 CVS, and 1134 amniocentesis were recorded over the 51-month study period in singleton pregnancies of women who desired prenatal screening and diagnostic testing. NIPT became the predominant FTS method by the second quarter following its introduction, increasing by 55.0% over the course of the study period. Total first-trimester risk assessments (NIPT+FTS) were not statistically different following NIPT (P = .312), but average monthly FTS procedures significantly decreased following NIPT introduction, decreasing by 48.7% over the course of the study period. Average monthly CVS and amniocentesis procedures significantly decreased following NIPT introduction, representing a 77.2% and 52.5% decrease in testing, respectively. Screening and testing per 100 morphological ultrasounds followed a similar trend. NIPT was quickly adopted by our high-risk patient population, and significantly decreased alternate prenatal screening and diagnostic testing in a short period of time.

Differential Effects of First-Trimester Screening Programs on Chorionic Villus Sampling

INTRODUCTION: The American College of Obstetricians and Gynecologists recommends that all women be offered screening for fetal aneuploidy regardless of maternal age. Two first-trimester screening programs are the first-trimester combined screen and noninvasive prenatal testing with positive screens followed up with invasive methods such as chorionic villus sampling (CVS). We show here the differing effects on CVS procedure rates after the introduction of first-trimester combined screen and noninvasive prenatal testing in a single practice. METHODS: Chorionic villus sampling and first-trimester combined screen procedures for a 9-year period were recorded from clinic billing information and evaluated 1) before first-trimester combined screen was offered (July 2004 to February 2006); 2) after first-trimester combined screen introduction but before noninvasive prenatal testing (March 2006 to February 2012); and 3) after noninvasive prenatal testing introduction (March 2012 to June 2013). Data were normalized per 1,000 targeted ultrasound scans to account for fluctuations in patient number and compared using analysis of variance. RESULTS: A total of 9,780 first-trimester combined screen and 608 CVS procedures were recorded during the 9-year study period. First-trimester combined screen peaked in 2009–2010 with 1,836 procedures but declined by 48.1% to 952 procedures after introduction of noninvasive prenatal testing. Monthly first-trimester combined screen and monthly first-trimester combined screen per 1,000 targeted ultrasound scans also significantly decreased postnoninvasive prenatal testing. During the same period, CVS increased from 55 to 100 procedures in 2007–2008 (81.8% increase from prefirst-trimester combined screen levels) but decreased to 22 procedures in 2012–2013 (78.0% decrease postnoninvasive prenatal testing). Furthermore, CVS procedures per 1,000 targeted ultrasound scans significantly increased after first-trimester combined screen but significantly decreased after noninvasive prenatal testing. CONCLUSION: The introduction of first-trimester combined screen caused a significant increase in CVS testing, whereas introduction of noninvasive prenatal testing caused a significant decrease in CVS testing.

Prenatal diagnostic conundrum involving a novel ATP7A duplication

Prenatal diagnostic conundrum involving a novel <i><scp>ATP7A</scp></i> duplication

Procedure-Related Complications after Genetic Amniocentesis and Chorionic Villus Sampling

Amniocentesis (AC) and chorionic villus sampling (CVS) play an important role in the diagnosis of genetic anomalies. The aim of this study was to evaluate presentable numbers of procedure-related complications of genetic interventions in a tertiary referral hospital. The pregnancy outcome of women who underwent genetic AC or CVS during 2003-2010 at the Department of Obstetrics and Gynecology, Medical University of Graz, Austria, was analyzed retrospectively. The primary outcome was miscarriage or membrane rupture after an invasive procedure. Only singleton gestations were included. 1,569 AC procedures and 334 CVS procedures (234 transabdominal, 99 transcervical, 1 with undocumented route) were performed. Of these, 57 cases were excluded from further analysis because of severe anomalies. Complete outcome data were available for 93.17% of cases. In 164 (8.89%) cases the pregnancy was terminated due to genetic anomalies or severe malformations. In the remaining collective 10 of 1,342 (0.75%) AC procedures, 3 of 150 (2.00%) transabdominal CVS procedures and 2 of 64 (3.13%) transcervical CVS procedures lead to complications resulting in miscarriage < 24 weeks (n = 13) or rupture of membranes (n = 2) within 2 weeks after procedure. Complication rates were significantly higher after CVS than after AC (OR 3.19). Over an observation period of seven years, the complication rates after AC, transabdominal CVS and transcervical CVS were 0.75%, 2.00% and 3.13%, respectively. These results are comparable to recent international investigations.

Chorionic villus sampling for abnormal screening compared to historical indications: prevalence of abnormal karyotypes

Objective: To determine the prevalence of abnormal karyotype results in women undergoing chorionic villus sampling (CVS) for abnormal first trimester screening compared to CVS for historical indications (advanced maternal age (AMA) or prior aneuploidy). Methods: Retrospective cohort of all patients undergoing CVS at Oregon Health & Science University from January 2006 to June 2010. Patients were separated based on CVS indication: (1) positive ultrasound (U/S) or serum screening; or (2) AMA or prior aneuploidy with normal or no screening. Prevalence of abnormal karyotype results were compared between groups. Results: Fetal karyotyping was successful in 500 of 506 CVS procedures performed. 203 CVS were performed for positive screening with 69 abnormal karyotypes (34.0%). 264 CVS were performed for historical indications with 11 abnormal karyotypes (4.2%). This difference was statistically significant (χ2 71.9, p < 0.001; OR 11.8 [95% CI 5.8, 24.6]). There were two age-related aneuplodies in AMA women without positive screening. 42 out of 44 AMA women diagnosed with aneuploidy (95.5%) had abnormal U/S and/or serum screening (35 U/S, 4 serum, 3 U/S and serum). Conclusions: Combined ultrasound and serum screening should be recommended to all women, including AMA women, prior to undergoing invasive testing to improve risk-based counseling and minimize morbidity.