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Ultrasound in Obstetrics & Gynecology :... Aug 2012To review the available evidence regarding pregnancy loss following first-trimester chorionic villus sampling (CVS) and mid-trimester genetic amniocentesis in twins. (Review)
Review
OBJECTIVE
To review the available evidence regarding pregnancy loss following first-trimester chorionic villus sampling (CVS) and mid-trimester genetic amniocentesis in twins.
METHODS
We searched the MEDLINE database from January 1990 to May 2011 for randomized and cohort studies reporting on the risk of pregnancy loss after first-trimester CVS performed between 9 and 14 weeks and after genetic amniocentesis performed between 14 and 22 weeks. Where appropriate, we calculated pooled proportions and relative risks with 95% CI.
RESULTS
No randomized studies were found. For CVS, nine studies fulfilled the inclusion criteria. The overall pregnancy-loss rate was 3.84% (95% CI, 2.48-5.47; n = 4). The rate of pregnancy loss before 20 weeks was 2.75% (95% CI, 1.28-4.75; n = 3) and before 28 weeks was 3.44% (95% CI, 1.67-5.81; n = 3). For amniocentesis, the overall pregnancy-loss rate was 3.07% (95% CI, 1.83-4.61; n = 4). The rate of pregnancy loss before 20 weeks was 2.25% (95% CI, 1.23-3.57; n = 2), before 24 weeks was 2.54% (95% CI, 1.43-3.96; n = 9) and before 28 weeks was 1.70% (95% CI, 0.37-3.97; n = 5). Pooled data from four case-control studies showed a higher risk (2.59% vs. 1.53%) of pregnancy loss before 24 weeks following amniocentesis (relative risk = 1.81; 95% CI, 1.02-3.19). There were no statistically significant differences in reported pregnancy loss between transabdominal and transcervical approaches, use of a single-needle system vs. a double-needle system and single uterine entry vs. double uterine entry in the CVS group. Similarly, in the amniocentesis group, there was no statistically significant difference in fetal loss between the single uterine entry vs. the double uterine entry.
CONCLUSION
In the absence of randomized studies, it is not possible to estimate accurately the excess risk following invasive procedures in twins. Currently available data show similar overall pregnancy-loss rates for both amniocentesis and CVS with the excess risk of around 1% above the background risk.
Topics: Amniocentesis; Chorionic Villi Sampling; Embryo Loss; Female; Humans; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Pregnancy, Twin
PubMed: 22125091
DOI: 10.1002/uog.10152 -
Prenatal Diagnosis May 2012Using published data, we sought to determine the amniocentesis-related loss rate in twin gestations. (Review)
Review
OBJECTIVE
Using published data, we sought to determine the amniocentesis-related loss rate in twin gestations.
METHODS
We searched the PUBMED database using keywords "amniocentesis", "twin" and "twins" to identify articles evaluating genetic amniocentesis in twin gestations published from January 1970 to December 2010. Random effects models were used to pool procedure-related loss rates from included studies.
RESULTS
The definition of "loss" varied across the 17 studies identified (Table 1). The pooled procedure-related loss rate at < 24 weeks was 3.5% (95% confidence interval [CI] 2.6-4.7) (Figure 2). Pooled loss rates at < 28 weeks (Figure 4) and to term (Figure 5) could not be calculated due to unacceptable heterogeneity of available data. Seven studies included a control (no amniocentesis) group and reported a pooled odds ratio for total pregnancy loss among cases of 1.8 (95% CI 1.2-2.7) (Figure 3). Only 1 study reported procedure-related loss rates by chorionicity (7.7% among monochorionics vs 1.4% among controls; p 0.02).
CONCLUSION
Analysis of published data demonstrated a pooled amniocentesis-related loss rate of 3.5% in twin gestations < 24 weeks. Pooled loss rates within other post-amniocentesis intervals or other gestational age windows and the impact of chorionicity on procedure-related loss rates cannot be determined from published data.
Topics: Amniocentesis; Female; Humans; Pregnancy; Twins
PubMed: 22028248
DOI: 10.1002/pd.2897 -
Fetal Diagnosis and Therapy 2009Pentasomy 49,XXXXY is a rare sex chromosome polysomy usually diagnosed postnatally by the combina- tion of mental retardation, facial dysmorphism, and genital, cardiac... (Review)
Review
OBJECTIVES
Pentasomy 49,XXXXY is a rare sex chromosome polysomy usually diagnosed postnatally by the combina- tion of mental retardation, facial dysmorphism, and genital, cardiac and skeletal malformations. Prenatal detection of 49,XXXXY is unusual and may be incidental due to non-specific ultrasound (US) findings. We report a case of 49,XXXXY diagnosed prenatally and present a literature review of the few prenatally diagnosed cases.
METHODS
We searched the PubMed electronic database without year and language restriction, using the keywords 'Prenatal', 'Diagnosis', and '49,XXXY', performing a systematic review.
RESULTS
We report a 35-year-old patient with normal first-trimester US but increased combined risk for trisomies 18 and 13. Amniocentesis at 16 weeks of gestation revealed a 49,XXXXY karyotype. Pregnancy was terminated at 19 weeks' gestation, and a male fetus with facial dysmorphism and hypospadia was delivered. A total of 12 articles were identified in the systematic review. All were case reports and dated from 1980 until 2008. The mean maternal age was 34.8 years (range 30-41). The most common prenatal US feature was cystic hygroma, present in 5 cases. Hypogenitalism was the most common macroscopic clinical feature identified after pathology examination in 7 cases. In 2 cases, there was an increase in first-trimester combined risk for trisomy 21.
CONCLUSIONS
Pentasomy 49,XXXXY is associated with a variety of non-specific US findings, of which cystic hygroma was the commonest. No specific sequence of findings could be identified in this review.
Topics: Adult; Amniocentesis; Aneuploidy; Female; Humans; Male; Pregnancy; Sex Chromosome Disorders
PubMed: 19816022
DOI: 10.1159/000236351 -
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... 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