A survey of current clinical practice of chorionic villus sampling.

OBJECTIVE: 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 10 years after the previous one to update the current clinical practice among clinicians who regularly perform CVS. METHOD: 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). RESULTS: 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. CONCLUSIONS: 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.

Instruments for chorionic villus sampling for prenatal diagnosis.

BACKGROUND: Chorionic villus sampling (CVS) is the method of choice for obtaining fetal tissue for prenatal diagnosis before 15 weeks of pregnancy. CVS can be performed using either a transabdominal or transcervical approach. The type of instrument and technique used could have a significant impact on the outcome of the procedure. An ability to manoeuvre the instrument within the uterine cavity without puncturing the gestational sac, to see the tip of the instrument on ultrasound scanning and to minimise the number of instrument passes into the uterus are particularly important. OBJECTIVES: To compare the efficacy and safety of different instruments and techniques used to obtain chorionic tissue in early pregnancy by the transabdominal or transcervical route. Primary outcomes included failure to obtain an adequate sample (greater than 5 mg of chorionic villi), need for reinsertion of the instrument, pain, and miscarriage following the procedure. Secondary outcomes included mean weight of tissue obtained, successful culture, difficult instrument insertion, poor visualisation of instrument, vaginal bleeding following the procedure and cost per procedure. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2012). SELECTION CRITERIA: Randomised trials comparing different instruments (forceps, cannula, needle) or techniques for CVS using either transabdominal or transcervical approach. DATA COLLECTION AND ANALYSIS: Two review authors assessed eligibility and trial quality. MAIN RESULTS: For transcervical CVS, forceps and cannulae were evaluated in five trials involving 472 women. When a cannula was used, operators failed to obtain an adequate sample (greater than 5 mg of chorionic villi) more often (average risk ratio (RR) 3.81; 95% confidence interval (CI) 1.52 to 9.56). There was no difference in the need for reinsertion of instruments (average RR 2.44; 95% CI 0.83 to 7.20). However, inserting a cannula was more painful (RR 1.93; 95% CI 1.11 to 3.37). There was no difference in spontaneous miscarriage when the use of a cannula was compared with biopsy forceps (RR 1.00; 95% CI 0.14 to 6.96). One study reported the cost of the procedures and found CVS with a cannula to be more expensive (mean difference (MD) $183.7; 95% CI 152.62 to 214.78).When different types of cannulae for transcervical CVS were compared, a Portex cannula was more likely to result in an inadequate sample (RR 2.23; 95% CI 1.25 to 3.98) compared with the silver cannula and to result in a difficult (RR 3.26; 95% CI 1.38 to 7.67) or painful (RR 5.81; 95% CI 1.41 to 23.88) procedure when compared with the aluminium cannula.For transabdominal CVS, two trials comparing different needle techniques were included involving 285 women. One study using an ex vivo system of term placentae was excluded. The included trials compared different continuous negative pressure aspiration techniques with a discontinuous negative pressure system created by a syringe attached to a 20 gauge needle. The studies produced discrepant results. One study found there was no significant difference between groups in the mean weight of chorionic villi obtained (MD 0.40; 95% CI -2.25 to 3.05) or in failure to obtain an adequate sample (more than 5 mg of chorionic villi) on the first attempt (RR 1.02; 95% CI 0.54 to 1.93), whereas the other study found both of these outcomes to be significantly less favourable with the standard discontinuous technique using a syringe (mean weight of chorionic villi obtained: MD -14.80; 95% CI -21.71 to -7.89; failure to obtain an adequate sample on the first attempt: RR 2.73; 95% CI 1.08 to 6.92). There was no difference in rate of miscarriage following the procedure in either study (RR 7.15; 95% CI 0.37 to 136.50; RR 2.93; 95% CI 0.12 to 70.00). Perceived pain by the patient was similar between groups (MD 0.00; 95% CI -0.04 to 0.04) as was success of culture (no failed cases). AUTHORS' CONCLUSIONS: For transcervical CVS, although there is some evidence to support the use of small forceps instead of cannulae, the evidence is not strong enough to support change in practice for clinicians who have become familiar with a particular technique. For transabdominal CVS, based on current evidence, there is no difference in clinically important outcomes with the use of a continuous compared with a discontinuous negative pressure needle aspiration system.

First trimester transabdominal chorionic villus sampling--does the needle matter?

PURPOSE: To compare first-trimester transabdominal chorionic villus samples (TA-CVS) when obtained by 20-gauge amniocentesis versus lancet needles. METHODS: This is a retrospective study of all women with viable singleton pregnancies undergoing TA-CVS from 01/01/2009 to 03/31/2011. All CVS were performed by a single operator using a freehand technique and amniocentesis needles from 01/01/2009 to 08/31/2010 and lancet needles from 09/01/2010 to 03/31/2011. All samples were processed by the same laboratory. RESULTS: There were no differences between groups regarding maternal age, weight, gestational age at CVS, indication for CVS, uterine position, or placental location. Lancet needles were associated with significantly larger samples (median 18 [range 3-40] versus 7 [range 1-33] mg, p < 0.0001), more successful in situ hybridization (96% versus 74.2%, p = 0.03), and faster result reporting (median 7 [range 5-12] versus 9 [range 6-26] days, p = 0.002). CONCLUSIONS: Needle type may be clinically important when selecting 20-gauge TA-CVS needles.

The transvaginal probe as a uterine manipulator: a new technique to simplify transabdominal chorionic villus sampling in cases with difficult access to the trophoblast.

OBJECTIVES: To evaluate the efficacy of using the transvaginal probe to manipulate the uterus and change the position of the trophoblast, and to simplify access to the chorionic villus under difficult conditions. METHODS: One thousand five hundred and thirty-nine procedures were performed in our centre in 1524 pregnant women from September 2006 to September 2009. In 90 of these, a difficult access to the trophoblast was observed and uterine manipulation under continuous ultrasound guidance with a double needle technique, was applied to obtain the sample. Of these, 86 samples were taken from singleton pregnancies and 4 from two bichorionic twin pregnancies RESULTS: One thousand five hundred and thirty-nine transabdominal chorionic villus sampling (TA-CVS) procedures were conducted on 1524 pregnant women. As many as 1449 were performed without manipulation with the transvaginal probe and in 90 cases the manipulation was carried out. In 89 cases, access to the trophoblast was difficult and the uterus was manipulated, which enabled an adequate TA-CVS to be performed with a single aspiration. In one case, TA-CVS was not performed due to significant pelvic pain in a patient with a fixed, retroflexed uterus and a previous history of endometriosis. CONCLUSIONS: Uterine manipulation with the transvaginal probe may be a useful solution in cases where TA-CVS is limited by difficult access to the trophoblast.

Evaluation of the feasibility of a new method for performing chorion villus sampling.

OBJECTIVE: This study aimed to evaluate the usefulness and safety of a new method for taking a placental biopsy. METHODS: The procedures were performed using the traditional single needle technique (group 1) or the new method (group 2). In group 2, the piston was fixed in a simple metallic clip and the negative pressure was maintained in a continuous manner which was controlled with a three-way stopcock. RESULTS: Multiple uterine insertion was necessary in 14 cases (32.6%) in group 1 and five (11.9%) in group 2 (p < 0.05). The amount of chorionic tissue obtained was significantly higher in group 2 (19.1 +/- 15.0 mg vs. 33.9 +/- 17.4 mg p < 0.05). The abortion rates did not differ in either group. CONCLUSION: While using this technique, the operator is capable of performing the procedure without any assistance and of applying constant negative pressure only in the placenta. The advantageous outcomes are probably related to the size as well as the incessant fashion of the vacuum force.

A randomized study to assess two different techniques of aspiration while performing transabdominal chorionic villus sampling.

OBJECTIVE: The technique used to perform transabdominal chorionic villus sampling (CVS) is not standardized, but aspiration of villi is generally obtained by discontinuous vacuum created in a syringe, manually or by a hand-grip device. We evaluated the feasibility of a new method of performing CVS which employs a 4-mL Vacutainer connected to the needle, producing a continuous negative pressure. METHODS: Two hundred pregnant women, whose gestational age ranged from 10 + 2 to 16 + 2 (mean, 12 + 1) weeks, entered the randomized study, which was powered to detect with 90% probability the absence of any difference in the size of chorionic samples obtained by using a 20-mL syringe with the vacuum obtained by a hand-grip device (Group 1) or by a vacutainer (Group 2). Four operators with different levels of experience performed all the procedures, which were done transabdominally using a freehand technique with a 20-gauge needle under ultrasound guidance. RESULTS: Maternal age, body mass index, gestational age and the way the needle was inserted within the chorion were similar in the two groups. The median amount of villi sampled was 20 mg, with no differences between the two groups. The rate of fetal loss was 1.7%. All losses occurred in women of Group 1 who had only one needle insertion. A second needle insertion was required more frequently while using the vacutainer. CONCLUSION: This new technique for performing transabdominal CVS uses a readily available device and is as effective as traditional sampling systems to aspirate villi. It has the advantage of being a one-operator procedure.

Pain experience during chorionic villus sampling and amniocentesis: a preliminary study.

OBJECTIVE: To investigate the maternal perception of pain before and after amniocentesis (AC) or transabdominal chorionic villus sampling (TA-CVS). STUDY DESIGN: Three hundred women were divided into groups of 100 participants destined to undergo three different fetal sampling procedures: amniocentesis (group 1), transabdominal chorionic villus sampling (CVS) with a 19 gauge Blache needle (group 2) and transabdominal CVS with a 20 gauge needle (group 3). The visual analog scale (VAS) was used to quantify the patient's pre-sampling expected pain level and the real pain level was measured immediately after the sampling procedure. The factors liable to influence the VAS score after the sampling procedure were studied by single and multivariate analysis and concerned either the sampling procedure or patient demographic data. RESULTS: The VAS scores obtained before the procedure were not significantly different for the three sampling groups. When performed with a 19 gauge Blache needle TA-CVS is significantly more painful than the other sampling procedures (p=0.0002): VAS score of 3.62 (group 2), 2.49 (group 3) and 2.68 (group 1) for CVS with 20 gauge needle and amniocentesis. Multivariate analysis identified a group of patients for which the perception of pain induced by sampling was higher compared to the other patients: nulliparous patients, having undergone 19 gauge Blache needle CVS, with a high pre-sampling VAS score. CONCLUSION: Transabdominal chorionic villus sampling with a 19 gauge Blache needle seems to be the most painful sampling procedure. We question the need to use a 19 gauge needle as acceptable results are obtained with a 20 gauge needle.

Chorionic villus sampling for early prenatal diagnosis at Bhumibol Adulyadej Hospital.

OBJECTIVE: To evaluate results of chorionic villus sampling for early prenatal diagnosis at Bhumibol Adulyadej Hospital. DESIGN: Retrospective descriptive study. SETTING: Perinatal unit, Department of Obstetrics and Gynaecology, Bhumibol Adulyadej Hospital. SUBJECTS: Three hundred and eighty three women were enrolled to chorionic villus sampling at the perinatal unit, Department of Obstetrics and Gynecology, Bhumibol Adulyadej Hospital, from November 10,1997 to October 17, 2006. RESULTS: During the present study periods three hundred and eighty three women were recruited, of these chorionic villus sampling for chromosome diagnosis were performed on 355 while 6 were for abnormal Thalassemia screening. Twenty two cases were excluded because ultrasound examination showed anembryonic pregnancy or fetal demise in utero in 13 cases, multiple fibroids in 4 cases, large area of placental hemorrhage in 3 cases, 1 case of multiple pregnancy and in 1 case the placenta was in an inappropriate position. The most common indication was elderly gravidarum (95.84%). Other indications were abnormal Thalassemia screening, abnormal ultrasound findings, family chromosome disorder previous Down syndrome, and severe oligohydramnios. The authors found eleven cases of chromosome abnormalities, four cases of maternal cell contamination and three cases of failed tissue culture (two cases from transcervical chorionic villus sampling and one case from transabdominal chorionic villus sampling) and two cases of mosaicism. There were two fetal losses in the present study and all the babies from the normal chromosome result looked normal. Second trimester amniocentesis following chorionic villus sampling was required due to maternal cell contamination, mosaicism and failed tissue culture. (2.77%) All cases had follow-up ultrasound scan during 18-20 weeks. CONCLUSION: The authors found that chorionic villus sampling is a possible alternative technique for prenatal diagnosis of cytogenetic abnormalities and abnormal Thalassemia screening in Thailand. It probably has a slightly higher rate of failed tissue culture and maternal cell contamination than amniocentesis, but it is generally done earlier in pregnancy than amniocentesis and is particularly advantageous for detecting certain genetic conditions.

Transabdominal chorionic villus sampling (CVS) for prenatal diagnosis of genetic disorders.

OBJECTIVE: To determine the safety and outcome of transabdominal Chorionic Villus Sampling (CVS) for prenatal diagnosis of genetic disorders. DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Department of Pathology, PNS Shifa, Karachi, from January 2003 to December 2004. PATIENTS AND METHODS: A total of 143 couples with request for prenatal diagnosis of various genetic disorders were studied. Transabdominal CVS was done under local anesthesia and ultrasound guidance. A Co-axial Chorion Biopsy needle set with an outer guide and an inner aspiration needle was used. The needle was introduced into the placenta in its longitudinal direction. Once the needle was adequately placed, the chorionic villi were aspirated with a to and fro jiggling movement of the aspiration needle and a suction force was applied through a syringe. Results were recorded and analyzed for descriptive statistics. RESULTS: A total of 144 CVSs were done in the outdoor on 143 couples including one with a twin pregnancy. The most common indication was b-thalassaemia (97%). Most procedures (76%) were done between 12 and 14 weeks (range 10-21 weeks). All placental positions including 52% anterior and 48% posterior were approachable through the trans-abdominal route. Most aspirations were easy, however, in 28% the aspiration was difficult due to a variety of factors. The overall success rate was 100%. In 85% of the cases sample yield was >25mg while in the remaining cases 10-25mg of sample was obtained that allowed a comfortable diagnosis. The procedure related abortion occurred in 1/144 (0.7%). CONCLUSION: Transabdominal CVS is a useful outdoor procedure for prenatal diagnosis. Placentae in almost any position can be approached without significant risk to the mother and the fetus.

Articulated needle guide: report on the first 30 cases.

This report represents our initial experience with a new type of needle guide for amniocentesis, transabdominal chorionic villus biopsies, and funipuncture developed at the Ohio State University and tested at the Harris Birthright Centre for Fetal Medicine. This articulated needle guide is designed to combine the advantages of the existing needle guides and the freehand technique. The needle guide offers improved maneuverability compared with standard needle guides and maintains easy visualization of the needle.

Instruments for transcervical chorionic villus sampling for prenatal diagnosis.

BACKGROUND: The type of instrument used in chorion villus sampling could have a significant impact on the success rate of the procedure. An ability to manoeuvre the instrument within the uterine cavity without puncturing the gestational sac, and to see the tip of the instrument on ultrasound scanning are particularly important. OBJECTIVES: The objective of this review was to assess the effects of different instruments for transcervical chorionic villus sampling on perinatal outcome, quality and quantity of obtained tissue, technical difficulties during the procedure and maternal adverse effects. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register was searched. Date of last search: October 1998. SELECTION CRITERIA: Randomised trials comparing different instruments for transcervical chorionic villus sampling. DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed by one reviewer. MAIN RESULTS: Three trials involving 268 women were included. None of the trials mentioned method of randomisation. An adequate sample was more likely to be obtained using small forceps than aspiration cannula (odds ratio 7.29, 95% confidence interval 3. 39 to 15.67). However small forceps were more difficult to insert than an aspiration cannula (odds ratio 0.35, 95% confidence interval 0.13 to 0.96). Use of the Portex cannula was more likely to result in an inadequate sample and a difficult or painful procedure when compared with either the silver or aluminium cannula respectively. REVIEWER'S CONCLUSIONS: Although there is some evidence to support the use of small forceps for transcervical chorionic villus sampling, it is not strong enough to support change in practice for clinicians who have become familiar with aspiration cannulas.

Instruments for chorionic villus sampling for prenatal diagnosis.

BACKGROUND: Chorionic villus sampling (CVS) is the method of choice for obtaining fetal tissue for prenatal diagnosis before 15 weeks of pregnancy. CVS can be performed using either transabdominal or transcervical approach. The type of instrument used could have a significant impact on the success rate of the procedure. An ability to manoeuvre the instrument within the uterine cavity without puncturing the gestational sac, and to see the tip of the instrument on ultrasound scanning are particularly important. OBJECTIVES: The objective of this review was to assess the effects of instruments used to obtain chorionic tissue in early pregnancy by transabdominal or transcervical route (chorionic villus sampling). The outcomes of interest were technical difficulties during the procedure, quality and quantity of obtained tissue, maternal adverse effects, pregnancy outcome and cost-effectiveness. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register was searched. Date of last search: November 2002. SELECTION CRITERIA: Randomised trials comparing different instruments (forceps, cannula, needle) for chorionic villus sampling using either transabdominal or transcervical approach. DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed by two reviewers. MAIN RESULTS: There were no trials comparing instruments for transabdominal CVS. Forceps and cannula were evaluated in five transcervical CVS trials involving 472 women. When a cannula was used, operators obtained an inadequate sample (less than 5 mg) more often (relative risk (RR) 4.21, 95% confidence interval (CI) 2.15 to 8.25). Compared with forceps, cannulae had to be re-inserted more often (RR 2.98, 95% CI 1.62 to 5.47). Also, inserting a cannula was more painful (RR 1.93, 95% CI 1.11 to 3.37). One study reported the cost of the procedures and found CVS with cannula to be more expensive (weighted mean difference $183.7, 95% confidence interval 152.62 to 214.78). When different types of cannulae were compared, Portex cannula was more likely to result in an inadequate sample and a difficult or painful procedure when compared with either the silver or aluminum cannula respectively. REVIEWER'S CONCLUSIONS: Although there is some evidence to support the use of small forceps for transcervical chorionic villus sampling, the evidence is not strong enough to support change in practice for clinicians who have become familiar with aspiration cannulae.

Chorionic villus sampling.

Chorionic villus sampling (CVS) has been used a successful and safe first-trimester prenatal diagnostic technique for over 12 years. Developed to avoid the medical and psychological complications of later prenatal diagnosis by amniocentesis, CVS rapidly has become a primary tool for the diagnosis of fetal cytogenetic, molecular, and biochemical disorders. In addition, its development has led to an improved understanding of several biological processes, including confined placental mosaicism and uniparental disomy.

First trimester prenatal diagnosis by transcervical chorionic villus sampling using curved biopsy forceps: lessons of the first 30 continuing pregnancies.

Transcervical chorionic villus sampling was performed on 30 pregnancies who were at risk for chromosomal abnormalities between 9 and 12 weeks of gestation to determine whether the developing fetus had a chromosomal disorder. Curved biopsy forceps were passed transcervically into the chorion frondosum under continuous real-time ultrasound guidance, and chorionic villi were biopsied. Chorion yield was assessed semiquantitatively. An adequate villus sample was obtained in all cases, giving a success rate of 100 per cent. The average weight of the villi was 18.8 mg with a lower limit of 10 mg which proved sufficient for diagnostic purposes. The villi were processed for chromosomal analyses by cultured preparations. A diagnostic result was achieved in 28 of cases (93.3%) within 2 weeks. No major maternal complications were encountered. The fetal loss rate was 3.3 per cent. No fetal anomalies were found in the study group. It is concluded that transcervical chorionic villus sampling appears to be a relatively safe and reliable procedure, but the risk of miscarriage can only be accurately assessed after further investigation. In contrast to amniocentesis, the procedure is performed early in pregnancy and results of the genetic test are available during the first trimester. We believe that transcervical chorionic villus sampling offers an alternative to amniocentesis in the detection of genetic disorders.

[Choriocentesis: comparison of the effectiveness of a new choriocentesis needle and a transcervical biopsy forceps]. / Choriocentèse: comparaison des performances d'une nouvelle aiguille à choriocentèse et de la pince à biopsie transcervicale.

71 samples taken by the transabdominal route were compared with 71 samples taken by forceps through the cervix. A fine (1 mm) transabdominal choriocentesis needle with a thin wall (0.1 mm), a short bevel, and a lateral hole was made to bring together simplicity, effectiveness and safety; success was obtained in 95% of the cases (39/41) of our last 41 samples on the first attempt. For comparison with the forceps, the success rate on the first attempt was only 66% (26/41), but it rose to 97.5% if the patient could take 3 attempts at most. The forceps made it possible to collect a mean quantity large enough (19.9 mg) but it was quite variable (16.7 mg being the range) of complete villi, whereas the choriocentesis needle only gathered a smaller volume (12.7 mg) but more reliable (the range being 3.7 mg). The villi were fragmented, however. To work out the study of the DNA and the karyotype, there is a choice between the forceps and the needle. This choice depends principally on the damage the two techniques can do. This has not been worked out yet in our study except indirectly.

[Chorionic villus needle sampling by the transabdominal route or by placental centesis. A series of 930 cases]. / Les prélèvements de villosités choriales à l'aiguille par voie transabdominale ou placentocentèses. Une série de 930 cas.

The authors report on a series of 930 chorion villus sampling diagnoses made with a needle by the transabdominal route, from January 1991 to October 1992 at the Prenatal Diagnosis Center in Marseille. Indications for prenatal diagnosis were: raised maternal age in 75% of cases (N:698); ultrasound findings in 11% (N:106), chromosome abnormalities in the family in 6% cases (N:53), raised human chorionic gonadotrophin in 4% cases (N:38), parental rearrangement in 2% cases (N:20), and sex linked disease in 1% (N:15). The success rate was 97% with 29 failures; the number of needle insertions was one in 97% cases and two in 3% cases. The average gestational age at sampling was related to the indications; 16 weeks of amenorrhoea for raised maternal age, and 22 weeks of amenorrhoea for ultrasound findings. Thirty one abnormalities were observed, four balanced translocations, and seven placental mosaicisms. Forty eight pregnancies terminated in abortion. The rate of fetal loss was 3.5% (7 cases) for the 200 first cases and 1% (8 cases) for the 730 following cases. Choriocentesis through the transabdominal route provides a diagnosis within a few days and the rate of fetal loss is close to that of amniocentesis. These arguments are in favour of an extension of this method of sampling.

PIP: Between January 1, 1991, and September 30, 1992, at the Prenatal Diagnostic Center in Marseille, France, physicians used a needle via the transabdominal route to take chorionic villus samples (CVS) from 930 pregnant women. The indications for CVS were advanced maternal age (75%), ultrasound findings (11%), chromosome abnormalities in the family (6%), high human chorionic gonadotropin levels (4%), chromosomal rearrangement in parent (s) (2%), and condition linked to chromosome X (1%). Only 1 needle puncture was needed in 97% of cases. CVS was successful in 97% of women. Heat denaturation did not allow a satisfactory structural analysis of chromosomes in 29 cases. The average gestational age at CVS was 16 weeks for advanced maternal age and 22 weeks for ultrasound findings. Cytogenetic tests were normal in 95.5% of cases. Chromosomal abnormalities were present in 31 cases, balanced translocations in 4 cases, and placental mosaicisms in 7 cases. 48 women chose to undergo medical abortion for chromosome abnormality in 31 cases and ultrasound-identified malformations in 17 cases. The fetal loss rate was 3.5% for the first 200 CVS cases compared to 1% for the next 730 cases. The fetal loss rate for CVS performed by trained and experienced professionals is similar to that for amniocentesis (0.4-1%). CVS via transabdominal route allowed a diagnosis within 24-28 hours for a chromosomal abnormality of numbers and several days for a structural abnormality. These findings support greater use of this method of CVS.

[Experience with chorionic villi sampling]. / Tapasztalataink chorionboholy-mintavétellel.

The authors discuss their experiences from 412 chorion villus samplings, (CVS), which they have done under four and a half years since 1985. They used eight types of instruments in performing their examinations and each instrument proved to be satisfactory in the gaining of chorion villus samples, suitable for further tests. They also discuss the bacteria found most frequently in the vagina on the basis of the examination and culturing of both vaginal and cervical fluid done prior to 151 CVS examinations and the effective method with which ascending infection can be prevented. They discuss a distributional pattern of their results based on the different indications for the CVS examinations, and the outcome of each of the pregnancies after CVS. In 377 cases they did direct karyotyping, in 30 cases DNA examination and in five cases enzyme determination also occurred.