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Obstetrics and Gynecology Sep 2007To compile a systematic review of complications related to genetic amniocentesis and chorionic villus sampling (CVS) to provide benchmark data for counseling and... (Review)
Review
OBJECTIVE
To compile a systematic review of complications related to genetic amniocentesis and chorionic villus sampling (CVS) to provide benchmark data for counseling and performance assessment of individual operators.
DATA SOURCES
We searched the MEDLINE database for articles published after January 1, 1995, that reported data for at least 100 women with singleton pregnancies with genetic amniocentesis after 14 weeks of pregnancy and reports of CVS carried out transabdominally between 10 and 14 weeks.
METHODS OF STUDY SELECTION
For amniocentesis, 29 articles fulfilled search criteria. Sixteen studies fulfilled search criteria for CVS.
TABULATION, INTEGRATION, AND RESULTS
After genetic amniocentesis, pooled pregnancy loss within 14 days was 0.6% (95% confidence interval [CI] 0.5-0.7), rising to 0.9% (95% CI 0.6-1.3) for pregnancy loss before 24 weeks and 1.9% (95% CI 1.4-2.5) for total pregnancy loss. Corresponding figures for CVS were 0.7%, 1.3%, and 2%. The data on multiple insertions showed large heterogeneity, ranging from 0.2% to 2.9% for amniocentesis (pooled risk 2.0%, 95% CI 0.9-3.6) and from 1.4% to 26.6% for CVS (pooled risk 7.8%, 95% CI 3.1-14.2). Only five amniocentesis studies provided controls, but none was matched for gestational age. Pooled relative risks for fetal loss before 28 weeks and total pregnancy loss were 1.46 (95% CI 0.86-2.49) and 1.25 (95% CI 1.02-1.53), respectively.
CONCLUSION
Although the risks of pregnancy loss are relatively low, lack of adequate controls tends to underestimate the true added risk of prenatal invasive procedures.
Topics: Abortion, Spontaneous; Amniocentesis; Chorionic Villi Sampling; Congenital Abnormalities; Female; Humans; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Risk Factors
PubMed: 17766619
DOI: 10.1097/01.AOG.0000278820.54029.e3 -
WITHDRAWN: Early amniocentesis versus transabdominal chorion villus sampling for prenatal diagnosis.The Cochrane Database of Systematic... Jul 2007A major disadvantage of amniocentesis is that test results are usually available only after 18 weeks gestation. Early amniocentesis can now be done between 9 to 14 weeks... (Review)
Review
BACKGROUND
A major disadvantage of amniocentesis is that test results are usually available only after 18 weeks gestation. Early amniocentesis can now be done between 9 to 14 weeks gestation.
OBJECTIVES
The objective was to assess the safety and accuracy of early amniocentesis compared with chorion villus sampling.
SEARCH STRATEGY
The Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register were searched. Date of last search: October 1998.
SELECTION CRITERIA
Randomised trials comparing early amniocentesis with transabdominal chorion villus sampling.
DATA COLLECTION AND ANALYSIS
One reviewer assessed eligibility and trial quality.
MAIN RESULTS
Three studies were included. Sampling failure was 0.4% in the early amniocentesis group compared to 2% in the chorion villus group (relative risk 0.23, 95% confidence interval 0.08 to 0.65). Consequently, more women in the chorion villus sampling group needed a second prenatal diagnostic test (relative risk 0.43, 95% confidence interval 0.21 to 0.88). There were no statistically significant differences in the laboratory failures (relative risk 0.43, 95% confidence interval 0.17 to 1.10) or number of women with various chromosomal abnormalities (relative risk 0.51, 95% confidence interval 0.26 to 1.04). Combined total pregnancy loss in the early amniocentesis group was 6.2% (57/915) compared with 5% (46/917) in the chorion villus sampling group (relative risk 1.24, 95% confidence interval 0.85 to 1.81). There were more spontaneous miscarriages after early amniocentesis (4.4% versus 2.3%, relative risk 1.92, 95% confidence interval 1.14 to 3.23). There was no difference in the incidence of neonatal respiratory distress and anomalies in the newborn infants. The incidence of talipes was greater in the early amniocentesis group, although haemangiomas were more common in the chorion villus sampling group.
AUTHORS' CONCLUSIONS
Current data suggest that early amniocentesis is associated with a greater risk of spontaneous miscarriage and neonatal talipes compared to transabdominal chorion villus sampling. An increased risk of these complications needs to be weighed against fewer technical difficulties and the possibility of fewer neonatal haemangiomas.
Topics: Amniocentesis; Chorionic Villi Sampling; Female; Humans; Pregnancy; Randomized Controlled Trials as Topic
PubMed: 17636584
DOI: 10.1002/14651858.CD000077 -
The Cochrane Database of Systematic... Apr 1996Amniocentesis test results are usually available only after 18 weeks gestation. Chorion villus sampling (CVS) may be performed transabdominally or transvaginally,... (Review)
Review
BACKGROUND
Amniocentesis test results are usually available only after 18 weeks gestation. Chorion villus sampling (CVS) may be performed transabdominally or transvaginally, usually between 10 and 12 weeks gestation.
OBJECTIVES
The objective of this review was to assess the safety and accuracy of chorion villus sampling compared to amniocentesis.
SEARCH STRATEGY
We searched the Cochrane Pregnancy and Childbirth Group trials register.
SELECTION CRITERIA
Randomised trials comparing first trimester chorion villus sampling and second trimester amniocentesis.
DATA COLLECTION AND ANALYSIS
Trial quality was assessed.
MAIN RESULTS
Three studies involving over 9000 women were included. The trials were generally of good quality. Compared to amniocentesis, chorion villus sampling was associated with more sampling and technical failures, and more false positive and false negative results. Pregnancy loss was more common after chorion villus sampling (odds ratio 1.33, 95% confidence interval 1.17 to 1.52). There is a suggestion (though not statistically significant) of an increase in stillbirths and neonatal deaths following chorion villus sampling. Maternal complications were uncommon.
AUTHORS' CONCLUSIONS
The increase in miscarriages after chorion villus sampling compared to amniocentesis appear to be procedure related. Second trimester amniocentesis appears to be safer than chorion villus sampling. The benefits of earlier diagnosis with chorion villus sampling must be set against the greater risk of pregnancy loss.
Topics: Chorionic Villi Sampling; Female; Humans; Pregnancy; Randomized Controlled Trials as Topic; Risk
PubMed: 17636578
DOI: 10.1002/14651858.CD000055 -
Journal of Obstetrics and Gynaecology... Jun 2006To assess the rate of fetal losses in twin pregnancies undergoing genetic mid-trimester amniocentesis. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To assess the rate of fetal losses in twin pregnancies undergoing genetic mid-trimester amniocentesis.
METHODS
In the first part of this investigation, a retrospective cohort study compared a group of women . 32 years old with twin pregnancies who underwent amniocentesis with a similar group unexposed to amniocentesis. Data were compiled from January 1990 to March 2004 for patients from a single institution. Pregnancies complicated by twin-to-twin transfusion syndrome, monoamniotic twins, or lethal fetal anomalies, and those treated by fetal reduction were excluded. The primary outcome was the loss of one or both fetuses prior to 24 weeks' gestation. In the second part of the investigation, a systematic review of the literature and a meta-analysis were performed.
RESULTS
In the first part of the study, data were collected for 132 women exposed to amniocentesis and 248 women not exposed to amniocentesis. There was no significant difference in the rate of fetal losses between the two groups (3.0% vs. 0.8%, P = 0.10). No losses occurred within four weeks of the procedure. In the second part of the investigation, four studies, including ours, were considered for a meta-analysis of 2026 women with twin pregnancies. Compared with women unexposed to the procedure, amniocentesis in women with twin pregnancies increased the risk of fetal losses prior to 20 to 24 weeks' gestation (odds ratio 2.42; 95% confidence intervals 1.24-4.74, P = 0.01) with an additional risk of one adverse outcome (1 or 2 fetal losses) for every 64 amniocenteses.
CONCLUSION
Genetic mid-trimester amniocentesis in twin pregnancies is associated.
Topics: Abortion, Spontaneous; Adult; Amniocentesis; Cohort Studies; Female; Gestational Age; Humans; Pregnancy; Pregnancy Trimester, Second; Pregnancy, Multiple; Retrospective Studies; Risk Factors; Twins
PubMed: 16857119
DOI: 10.1016/s1701-2163(16)32171-5 -
Journal of Obstetrics and Gynaecology... Nov 2003To provide information regarding the use of folic acid for the prevention of neural tube defects (NTDs) and other congenital anomalies, in order that physicians,... (Review)
Review
OBJECTIVE
To provide information regarding the use of folic acid for the prevention of neural tube defects (NTDs) and other congenital anomalies, in order that physicians, midwives, nurses, and other health-care workers can assist in the education of women in the preconception phase of their health care. OPTION: Folic acid supplementation is problematic, since 50% of pregnancies are unplanned and the health status of women may not be optimal.
OUTCOMES
Folic acid supplementation has been proven to decrease or minimize specific birth defects.
EVIDENCE
A systematic review of the literature, including review and peer-reviewed articles, government publications, the previous Society of Obstetricians and Gynaecologists of Canada (SOGC) Policy Statement of March 1993, and statements from the American College of Obstetrics and Gynecology, was used to develop a new clinical practice guideline for the SOGC.
VALUES
Peer-review process within the committee structure.
BENEFITS, HARMS, AND COSTS
The benefit is reduced lethal and severe morbidity birth defects and the harm is minimal. The personal cost is of vitamin supplementation on a daily basis and eating a healthy diet.
RECOMMENDATIONS
1. Women in the reproductive age group should be advised about the benefits of folic acid supplementation during wellness visits (birth control renewal, Pap testing, yearly examination), especially if pregnancy is contemplated. (III-A) 2. Women should be advised to maintain a healthy nutritional diet, as recommended in Canada's Food Guide to Healthy Eating (good or excellent sources of folic acid: broccoli, spinach, peas, Brussels sprouts, corn, beans, lentils, oranges). (III-A) 3. Women who could become pregnant should be advised to take a multivitamin containing 0.4 mg to 1.0 mg of folic acid daily. (II-1A) 4. Women taking a multivitamin with folic acid supplement should be advised not to take more than 1 daily dose of vitamin supplement, as indicated on the product label. (II-2A) 5. Women in intermediate- to high-risk categories for NTDs (NTD-affected previous pregnancy, family history, insulin-dependent diabetes, epilepsy treatment with valproic acid or carbamazepine) should be advised that high-dose folic acid (4.0 mg-5.0 mg daily) supplementation is recommended. This should be taken as folic acid alone, not in a multivitamin format, due to risk of excessive intake of other vitamins such as vitamin A. (I-A) 6. The choice of a 5 mg folic acid daily dose for women considering a pregnancy should be made under medical supervision after minimizing the risk of undiagnosed vitamin B12 deficiency (hypersegmentation of polymorphonuclear cells, macrocystic indices, large ovalocytes, leukopenia, thrombocytopenia, markedly elevated lactate dehydrogenase level, confirmed red blood cell folate level). (II-2A) 7. Signs or symptoms of vitamin B12 deficiency should be considered before initiating folic acid supplementation of doses greater than 1.0 mg. (III-A) 8. A three-generation pedigree on the families of both the pregnant woman and the biological father should be obtained to identify increased risk for congenital birth defects (i.e., NTD, cardiac, chromosomal, genetic). (III-A) 9. Women who become pregnant should be advised of the availability of noninvasive screening tests and invasive diagnostic tests for congenital birth defects (including NTDs): maternal serum "triple marker screen" at 15 to 20 weeks, ultrasound at 16 to 20 weeks, and amniocentesis after 15 weeks of pregnancy if a positive screening test is present. (I-A) VALIDATION: This is a revision of a previous guideline and information from other consensus reviews from medical and government publications has been used.
Topics: Canada; Congenital Abnormalities; Female; Folic Acid; Humans; Neural Tube Defects; Pregnancy; Prenatal Care
PubMed: 14608448
DOI: 10.1016/s1701-2163(16)30248-1 -
The Cochrane Database of Systematic... 2003A major disadvantage of second trimester amniocentesis is that the result is usually available only after 18 weeks' gestation. Chorionic villus sampling (CVS) and early... (Review)
Review
BACKGROUND
A major disadvantage of second trimester amniocentesis is that the result is usually available only after 18 weeks' gestation. Chorionic villus sampling (CVS) and early amniocentesis can be done between 9 and 14 weeks and offer an earlier alternative.
OBJECTIVES
The objective was to assess comparative safety and accuracy of second trimester amniocentesis, early amniocentesis, transcervical and transabdominal CVS.
SEARCH STRATEGY
We searched the Cochrane Pregnancy and Childbirth Group trials register (March 2003) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2002).
SELECTION CRITERIA
All randomised trials comparing amniocentesis and CVS.
DATA COLLECTION AND ANALYSIS
Two reviewers assessed eligibility and trial quality and performed data extraction. We analysed the data using RevMan software.
MAIN RESULTS
A total of 14 randomised studies have been included. In a low risk population with a background pregnancy loss of around 2%, a second trimester amniocentesis will increase this risk by another 1%. This difference did not reach statistical significance, but the increase in spontaneous miscarriages following second trimester amniocentesis compared with controls (no amniocentesis) did (2.1% versus 1.3%; relative risk (RR) 1.02 to 2.52). Early amniocentesis is not a safe early alternative to second trimester amniocentesis because of increased pregnancy loss (7.6% versus 5.9%; RR 1.29, 95% CI 1.03 to 1.61) and higher incidence of talipes compared to CVS (1.8% versus 0.2%; RR 6.43, 95% CI 1.68 to 24.64).Compared with second trimester amniocentesis, transcervical CVS carries a significantly higher risk of pregnancy loss (14.5% versus 11%; RR 1.40, 95% CI 1.09 to 1.81) and spontaneous miscarriage (12.9% versus 9.4%; RR 1.50, 95% CI 1.07 to 2.11). One study compared transabdominal CVS with second trimester amniocentesis and found no significant difference in the total pregnancy loss between the two procedures (6.3% versus 7%). Transcervical CVS is more technically demanding than transabdominal CVS with more failures to obtain sample and more multiple insertions.
REVIEWER'S CONCLUSIONS
Second trimester amniocentesis is safer than transcervical CVS and early amniocentesis. If earlier diagnosis is required, transabdominal CVS is preferable to early amniocentesis or transcervical CVS. In circumstances where transabdominal CVS may be technically difficult the preferred options are transcervical CVS in the first trimester or second trimester amniocentesis.
Topics: Amniocentesis; Chorionic Villi Sampling; Congenital Abnormalities; Female; Humans; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Randomized Controlled Trials as Topic
PubMed: 12917956
DOI: 10.1002/14651858.CD003252 -
The Cochrane Database of Systematic... 2001Twin-twin transfusion syndrome, a condition affecting monochorionic twin pregnancies, is associated with a high risk of perinatal mortality and morbidity. A number of... (Review)
Review
BACKGROUND
Twin-twin transfusion syndrome, a condition affecting monochorionic twin pregnancies, is associated with a high risk of perinatal mortality and morbidity. A number of treatments have been introduced to treat the condition but it is unclear which intervention improves maternal and fetal outcome.
OBJECTIVES
The objective of this review was to evaluate the impact of treatment modalities in twin-twin transfusion syndrome.
SEARCH STRATEGY
We searched The Cochrane Pregnancy and Childbirth Trials Register and Cochrane Controlled Trials Register. We also searched conference proceedings and made personal contact with experts active in the area of the review. Date of last search: August 2000.
SELECTION CRITERIA
Randomised and quasi-randomised studies of amnioreduction versus laser coagulation, septostomy versus laser coagulation or septostomy versus amnioreduction.
DATA COLLECTION AND ANALYSIS
Eligibility was assessed by one reviewer. Study authors were contacted for additional information.
MAIN RESULTS
No studies were included.
REVIEWER'S CONCLUSIONS
There is no current evidence from randomised trials to influence practice. Three ongoing randomised studies have been identified.
Topics: Amniocentesis; Amnion; Female; Fetofetal Transfusion; Humans; Laser Coagulation; Pregnancy; Pregnancy Reduction, Multifetal; Punctures; Randomized Controlled Trials as Topic
PubMed: 11279749
DOI: 10.1002/14651858.CD002073 -
The Cochrane Database of Systematic... 2000A major disadvantage of amniocentesis is that test results are usually available only after 18 weeks gestation. Early amniocentesis can now be done between 9 to 14 weeks... (Review)
Review
BACKGROUND
A major disadvantage of amniocentesis is that test results are usually available only after 18 weeks gestation. Early amniocentesis can now be done between 9 to 14 weeks gestation.
OBJECTIVES
The objective was to assess the safety and accuracy of early amniocentesis compared with chorion villus sampling.
SEARCH STRATEGY
The Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register were searched. Date of last search: October 1998.
SELECTION CRITERIA
Randomised trials comparing early amniocentesis with transabdominal chorion villus sampling.
DATA COLLECTION AND ANALYSIS
One reviewer assessed eligibility and trial quality.
MAIN RESULTS
Three studies were included. Sampling failure was 0.4% in the early amniocentesis group compared to 2% in the chorion villus group (relative risk 0.23, 95% confidence interval 0.08 to 0.65). Consequently, more women in the chorion villus sampling group needed a second prenatal diagnostic test (relative risk 0.43, 95% confidence interval 0.21 to 0.88). There were no statistically significant differences in the laboratory failures (relative risk 0.43, 95% confidence interval 0. 17 to 1.10) or number of women with various chromosomal abnormalities (relative risk 0.51, 95% confidence interval 0.26 to 1. 04). Combined total pregnancy loss in the early amniocentesis group was 6.2% (57/915) compared with 5% (46/917) in the chorion villus sampling group (relative risk 1.24, 95% confidence interval 0.85 to 1.81). There were more spontaneous miscarriages after early amniocentesis (4.4% versus 2.3%, relative risk 1.92, 95% confidence interval 1.14 to 3.23). There was no difference in the incidence of neonatal respiratory distress and anomalies in the newborn infants. The incidence of talipes was greater in the early amniocentesis group, although haemangiomas were more common in the chorion villus sampling group.
REVIEWER'S CONCLUSIONS
Current data suggest that early amniocentesis is associated with a greater risk of spontaneous miscarriage and neonatal talipes compared to transabdominal chorion villus sampling. An increased risk of these complications needs to be weighed against fewer technical difficulties and the possibility of fewer neonatal haemangiomas.
Topics: Amniocentesis; Chorionic Villi Sampling; Female; Humans; Pregnancy; Randomized Controlled Trials as Topic
PubMed: 10796116
DOI: 10.1002/14651858.CD000077 -
The Cochrane Database of Systematic... 2000Amniocentesis test results are usually available only after 18 weeks gestation. Chorion villus sampling (CVS) may be performed transabdominally or transvaginally,... (Review)
Review
BACKGROUND
Amniocentesis test results are usually available only after 18 weeks gestation. Chorion villus sampling (CVS) may be performed transabdominally or transvaginally, usually between 10 and 12 weeks gestation.
OBJECTIVES
The objective of this review was to assess the safety and accuracy of chorion villus sampling compared to amniocentesis.
SEARCH STRATEGY
We searched the Cochrane Pregnancy and Childbirth Group trials register.
SELECTION CRITERIA
Randomised trials comparing first trimester chorion villus sampling and second trimester amniocentesis.
DATA COLLECTION AND ANALYSIS
Trial quality was assessed.
MAIN RESULTS
Three studies involving over 9000 women were included. The trials were generally of good quality. Compared to amniocentesis, chorion villus sampling was associated with more sampling and technical failures, and more false positive and false negative results. Pregnancy loss was more common after chorion villus sampling (odds ratio 1.33, 95% confidence interval 1.17 to 1.52). There is a suggestion (though not statistically significant) of an increase in stillbirths and neonatal deaths following chorion villus sampling. Maternal complications were uncommon.
REVIEWER'S CONCLUSIONS
The increase in miscarriages after chorion villus sampling compared to amniocentesis appear to be procedure related. Second trimester amniocentesis appears to be safer than chorion villus sampling. The benefits of earlier diagnosis with chorion villus sampling must be set against the greater risk of pregnancy loss.
Topics: Chorionic Villi Sampling; Female; Humans; Pregnancy; Randomized Controlled Trials as Topic; Risk
PubMed: 10796107
DOI: 10.1002/14651858.CD000055