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The Cochrane Database of Systematic... Sep 2017During pregnancy, fetal cells suitable for genetic testing can be obtained from amniotic fluid by amniocentesis (AC), placental tissue by chorionic villus sampling... (Review)
Review
BACKGROUND
During pregnancy, fetal cells suitable for genetic testing can be obtained from amniotic fluid by amniocentesis (AC), placental tissue by chorionic villus sampling (CVS), or fetal blood. A major disadvantage of second trimester amniocentesis is that the results are available relatively late in pregnancy (after 16 weeks' gestation). Earlier alternatives are chorionic villus sampling (CVS) and early amniocentesis, which can be performed in the first trimester of pregnancy.
OBJECTIVES
The objective of this review was to compare the safety and accuracy of all types of AC (i.e. early and late) and CVS (e.g. transabdominal, transcervical) for prenatal diagnosis.
SEARCH METHODS
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (3 March 2017), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP; 3 March 2017), and reference lists of retrieved studies.
SELECTION CRITERIA
All randomised trials comparing AC and CVS by either transabdominal or transcervical route.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. The quality of the evidence was assessed using the GRADE approach.
MAIN RESULTS
We included a total of 16 randomised studies, with a total of 33,555 women, 14 of which were deemed to be at low risk of bias. The number of women included in the trials ranged from 223 to 4606.Studies were categorized into six comparisons: 1. second trimester AC versus control; 2. early versus second trimester AC; 3. CVS versus second trimester AC; 4. CVS methods; 5. Early AC versus CVS; and 6. AC with or without ultrasound.One study compared second trimester AC with no AC (control) in a low risk population (women = 4606). Background pregnancy loss was around 2%. Second trimester AC compared to no testing increased total pregnancy loss by another 1%. The confidence intervals (CI) around this excess risk were relatively large (3.2% versus 2.3 %, average risk ratio (RR) 1.41, 95% CI 0.99 to 2.00; moderate-quality evidence). In the same study, spontaneous miscarriages were also higher (2.1% versus 1.3%; average RR 1.60, 95% CI 1.02 to 2.52; high-quality evidence). The number of congenital anomalies was similar in both groups (2.0% versus 2.2%, average RR 0.93, 95% CI 0.62 to 1.39; moderate-quality evidence).One study (women = 4334) found that early amniocentesis was not a safe early alternative compared to second trimester amniocentesis because of increased total pregnancy losses (7.6% versus 5.9%; average RR 1.29, 95% CI 1.03 to 1.61; high-quality evidence), spontaneous miscarriages (3.6% versus 2.5%, average RR 1.41, 95% CI 1.00 to 1.98; moderate-quality evidence), and a higher incidence of congential anomalies, including talipes (4.7% versus 2.7%; average RR 1.73, 95% CI 1.26 to 2.38; high-quality evidence).When pregnancy loss after CVS was compared with second trimester AC, there was a clinically significant heterogeneity in the size and direction of the effect depending on the technique used (transabdominal or transcervical), therefore, the results were not pooled. Only one study compared transabdominal CVS with second trimester AC (women = 2234). They found no clear difference between the two procedures in the total pregnancy loss (6.3% versus 7%; average RR 0.90, 95% CI 0.66 to 1.23, low-quality evidence), spontaneous miscarriages (3.0% versus 3.9%; average RR 0.77, 95% CI 0.49 to 1.21; low-quality evidence), and perinatal deaths (0.7% versus 0.6%; average RR 1.18, 95% CI 0.40 to 3.51; low-quality evidence). Transcervical CVS may carry a higher risk of pregnancy loss (14.5% versus 11.5%; average RR 1.40, 95% CI 1.09 to 1.81), but the results were quite heterogeneous.Five studies compared transabdominal and transcervical CVS (women = 7978). There were no clear differences between the two methods in pregnancy losses (average RR 1.16, 95% CI 0.81 to 1.65; very low-quality evidence), spontaneous miscarriages (average RR 1.68, 95% CI 0.79 to 3.58; very low-quality evidence), or anomalies (average RR 0.68, 95% CI 0.41 to 1.12; low-quality evidence). We downgraded the quality of the evidence to low due to heterogeneity between studies. Transcervical CVS may be more technically demanding than transabdominal CVS, with more failures to obtain sample (2.0% versus 1.1%; average RR 1.79, 95% CI 1.13 to 2.82, moderate-quality evidence).Overall, we found low-quality evidence for outcomes when early amniocentesis was compared to transabdominal CVS. Spontaneous miscarriage was the only outcome supported by moderate-quality evidence, resulting in more miscarriages after early AC compared with transabdominal CVS (2.3% versus 1.3%; average RR 1.73, 95% CI 1.15 to 2.60). There were no clear differences in pregnancy losses (average RR 1.15, 95% CI 0.86 to 1.54; low-quality evidence), or anomalies (average RR 1.14, 95% CI 0.57 to 2.30; very low-quality evidence).We found one study that examined AC with or without ultrasound, which evaluated a type of ultrasound-assisted procedure that is now considered obsolete.
AUTHORS' CONCLUSIONS
Second trimester amniocentesis increased the risk of pregnancy loss, but it was not possible to quantify this increase precisely from only one study, carried out more than 30 years ago.Early amniocentesis was not as safe as second trimester amniocentesis, illustrated by increased pregnancy loss and congenital anomalies (talipes). Transcervical chorionic villus sampling compared with second trimester amniocentesis may be associated with a higher risk of pregnancy loss, but results were quite heterogeneous.Diagnostic accuracy of different methods could not be assessed adequately because of incomplete karyotype data in most studies.
Topics: Amniocentesis; Chorionic Villi Sampling; Congenital Abnormalities; Female; Humans; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Randomized Controlled Trials as Topic
PubMed: 28869276
DOI: 10.1002/14651858.CD003252.pub2 -
Ultrasound in Obstetrics & Gynecology :... Oct 2019To estimate the procedure-related risk of miscarriage after amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and an... (Comparative Study)
Comparative Study Meta-Analysis
OBJECTIVE
To estimate the procedure-related risk of miscarriage after amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and an updated meta-analysis.
METHODS
A search of MEDLINE, EMBASE and The Cochrane Library was carried out to identify studies reporting complications following CVS or amniocentesis. Eligible for inclusion were large controlled studies reporting data for pregnancy loss prior to 24 weeks' gestation. Study authors were contacted when required to identify additional necessary data. Data for cases that had an invasive procedure and controls were inputted into contingency tables and the risk of miscarriage was estimated for each study. Summary statistics based on a random-effects model were calculated after taking into account the weighting for each study included in the systematic review. Procedure-related risk of miscarriage was estimated as a weighted risk difference from the summary statistics for cases and controls. Subgroup analyses were performed according to the similarity in risk levels for chromosomal abnormality between the invasive-testing and control groups. Heterogeneity was assessed using the I statistic. Egger's bias was estimated to assess reporting bias in published studies.
RESULTS
The electronic search yielded 2943 potential citations, from which 12 controlled studies for amniocentesis and seven for CVS were selected for inclusion in the systematic review. A total of 580 miscarriages occurred following 63 723 amniocentesis procedures, resulting in a weighted risk of pregnancy loss of 0.91% (95% CI, 0.73-1.09%). In the control group, there were 1726 miscarriages in 330 469 pregnancies with a loss rate of 0.58% (95% CI, 0.47-0.70%). The weighted procedure-related risk of miscarriage following amniocentesis was 0.30% (95% CI, 0.11-0.49%; I = 70.1%). A total of 163 miscarriages occurred following 13 011 CVS procedures, resulting in a risk of pregnancy loss of 1.39% (95% CI, 0.76-2.02%). In the control group, there were 1946 miscarriages in 232 680 pregnancies with a loss rate of 1.23% (95% CI, 0.86-1.59%). The weighted procedure-related risk of miscarriage following CVS was 0.20% (95% CI, -0.13 to 0.52%; I = 52.7%). However, when studies including only women with similar risk profiles for chromosomal abnormality in the intervention and control groups were considered, the procedure-related risk for amniocentesis was 0.12% (95% CI, -0.05 to 0.30%; I = 44.1%) and for CVS it was -0.11% (95% CI, -0.29 to 0.08%; I = 0%).
CONCLUSIONS
The procedure-related risks of miscarriage following amniocentesis and CVS are lower than currently quoted to women. The risk appears to be negligible when these interventions were compared to control groups of the same risk profile. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Abortion, Spontaneous; Adult; Amniocentesis; Chorionic Villi Sampling; Chromosome Aberrations; Embryo Loss; Female; Gestational Age; Humans; Pregnancy; Pregnancy Trimester, Second; Prenatal Diagnosis; Randomized Controlled Trials as Topic; Risk Assessment
PubMed: 31124209
DOI: 10.1002/uog.20353 -
Minerva Ginecologica Apr 2018The aim of this paper was to estimate the risk of miscarriage after amniocentesis or chorionic villus sampling (CVS) based on a systematic review of the literature. (Comparative Study)
Comparative Study Review
INTRODUCTION
The aim of this paper was to estimate the risk of miscarriage after amniocentesis or chorionic villus sampling (CVS) based on a systematic review of the literature.
EVIDENCE ACQUISITION
A search of Medline, Embase, and The Cochrane Library (2000-2017) was carried out to identify studies reporting complications following CVS or amniocentesis. The inclusion criteria for the systematic review were studies reporting results from large controlled studies (N.≥1000 invasive procedures) and those reporting data for pregnancy loss prior to 24 weeks' gestation. Data for cases that had invasive procedure and controls were inputted in contingency tables and risk of miscarriage was estimated for each study. Summary statistics were calculated after taking into account the weighting for each study included in the systematic review. Procedure-related risk of miscarriage was estimated as a weighted risk difference from the summary statistics for cases and controls.
EVIDENCE SNTHESIS
The electronic search from the databases yielded 2465 potential citations of which 2431 were excluded, leaving 34 studies for full-text review. The final review included 10 studies for amniocentesis and 6 studies for CVS, which were used to estimate risk of miscarriage in pregnancies that had an invasive procedure and the control pregnancies that did not. The procedure-related risk of miscarriage following amniocentesis was 0.35% (95% confidence interval [CI]: 0.07 to 0.63) and that following CVS was 0.35% (95% CI: -0.31 to 1.00).
CONCLUSIONS
The procedure-related risks of miscarriage following amniocentesis and CVS are lower than currently quoted to women.
Topics: Abortion, Spontaneous; Amniocentesis; Chorionic Villi Sampling; Female; Gestational Age; Humans; Pregnancy; Risk
PubMed: 29161799
DOI: 10.23736/S0026-4784.17.04178-8 -
Viruses Oct 2023Cytomegalovirus (CMV) infection is a significant health concern affecting numerous expectant mothers across the globe. CMV is the leading cause of health problems and... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
Cytomegalovirus (CMV) infection is a significant health concern affecting numerous expectant mothers across the globe. CMV is the leading cause of health problems and developmental delays among infected infants. Notably, this study examines CMV infection in pregnancy, its management, prevention mechanisms, and treatment options.
METHODS
Specifically, information from the Cochrane Library, PUBMED, Wiley Online, Science Direct, and Taylor Francis databases were reviewed along with additional records identified through the register, the Google Scholar search engine. Based on the search, 21 articles were identified for systematic review.
RESULTS
A total of six randomized controlled trials (RCTs) were utilized for a meta-analytic review. As heterogeneity was substantial, the random effects model was used for meta-analysis. Utilizing the random-effects model, the restricted maximum likelihood (REML) approach, the estimate of effect size (d = -0.479, 95% CI = -0.977 to 0.019, = 0.060) suggests the results are not statistically significant, so it cannot be inferred that the prevention methods used were effective, despite an inverse relationship between treatment and number of infected cases. The findings indicated that several techniques are used to prevent, diagnose, and manage CMV infection during pregnancy, including proper hygiene, ultrasound examination (US), magnetic resonance imaging (MRI), amniocentesis, viremia, hyperimmunoglobulin (HIG), and valacyclovir (VACV).
CONCLUSIONS
The current review has significant implications for addressing CMV infection in pregnancy. Specifically, it provides valuable findings on contemporary management interventions to prevent and treat CMV infection among expectant mothers. Therefore, it allows relevant stakeholders to address these critical health concerns and understand the effectiveness of the proposed prevention and treatment options.
Topics: Pregnancy; Infant; Female; Humans; Pregnancy Complications, Infectious; Cytomegalovirus Infections; Amniocentesis; Infectious Disease Transmission, Vertical
PubMed: 38005820
DOI: 10.3390/v15112142 -
Ultrasound in Obstetrics & Gynecology :... Feb 2023Cytomegalovirus (CMV) DNA is detectable in the amniotic fluid collected by amniocentesis in cases in which the fetus has been infected. However, cases of congenital... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Cytomegalovirus (CMV) DNA is detectable in the amniotic fluid collected by amniocentesis in cases in which the fetus has been infected. However, cases of congenital neonatal CMV infection with a negative amniocentesis result have also been reported in the literature. The aim of the present study was to compare pregnancies with a negative amniocentesis result to those with a positive amniocentesis result in terms of incidence of fetal insult and long-term sequelae.
METHODS
Observational studies that included pregnant women with CMV infection who underwent amniocentesis and that reported their results together with neonatal and/or long-term outcomes of the offspring were included. The risk of bias in included studies was assessed using the Newcastle-Ottawa Scale. The rate of severe symptoms at birth, defined as neurological symptoms or multiorgan involvement at birth, and the rate of severe sensorineural hearing loss (SNHL) and/or neurodevelopmental impairment at follow-up were the main outcomes of the study. The secondary outcome was the rate of pregnancy termination due to the presence of CMV-associated central nervous system (CNS) findings or multiorgan involvement on ultrasound/magnetic resonance imaging (MRI).
RESULTS
Seven studies were included in the systematic review and meta-analysis. The pooled false-negative rate of amniocentesis was 8.0% (95% CI, 5.0-13.0%). The pooled rate of severe symptoms at birth was 0.0% (95% CI, 0.0-1.0%; I = 0%) in fetuses with a negative amniocentesis result and 22.0% (95% CI, 11.0-38.0%; I = 75%) in those with a positive amniocentesis result. The pooled odds ratio (OR) was 0.03 (95% CI, 0.01-0.10; I = 0%). The pooled rate of severe SNHL and/or neurodevelopmental impairment at follow-up in fetuses with a negative amniocentesis result was 0.0% (95% CI, 0.0-1.0%; I = 0%) and, in those with a positive amniocentesis result, it was 14.0% (95% CI, 7.0-26.0%; I = 64%). The pooled OR was 0.04 (95% CI, 0.01-0.14; I = 0%). The pooled rate of pregnancy termination due to the presence of CMV-associated CNS findings or multiorgan involvement on ultrasound/MRI was 0.0% (95% CI, 0.0-2.0%; I = 0%) in fetuses with a negative amniocentesis result and 20.0% (95% CI, 10.0-36.0%; I = 82%) in those with a positive amniocentesis result. The pooled OR was 0.03 (95% CI, 0.01-0.08; I = 0%). A subgroup analysis including only pregnancies with primary CMV infection and a sensitivity analysis including only prospective studies were carried out, showing very similar results to those of the main analysis.
CONCLUSION
A negative amniocentesis result in pregnant women with CMV infection ensures lack of fetal insult and long-term sequelae to the child, even if transmission has occurred. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Topics: Infant, Newborn; Child; Pregnancy; Infant; Female; Humans; Amniocentesis; Pregnancy Complications, Infectious; Prospective Studies; Cytomegalovirus; Cytomegalovirus Infections; Infectious Disease Transmission, Vertical; Observational Studies as Topic
PubMed: 36412976
DOI: 10.1002/uog.26128 -
Journal de Gynecologie, Obstetrique Et... Dec 2014Study of epidemiology of pregnancy loss. (Review)
Review
OBJECTIVES
Study of epidemiology of pregnancy loss.
MATERIALS AND METHOD
A systematic review of the literature was performed using Pubmed and the Cochrane library databases and the guidelines from main international societies.
RESULTS
The occurrence of first trimester miscarriage is 12% of pregnancies and 25% of women. Miscarriage risk factors are ages of woman and man, body mass index greater than or equal to 25kg/m(2), excessive coffee drinking, smoking and alcohol consumption, exposure to magnetic fields and ionizing radiation, history of abortion, some fertility disorders and impaired ovarian reserve. Late miscarriage (LM) complicates less than 1% of pregnancies. Identified risk factors are maternal age, low level of education, living alone, history of previous miscarriage, of premature delivery and of previous termination of pregnancy, any uterine malformation, trachelectomy, existing bacterial vaginosis, amniocentesis, a shortened cervix and a dilated cervical os with prolapsed membranes. Fetal death in utero has a prevalence of 2% in the world and 5/1000 in France. Its main risk factors are detailed in the chapter.
Topics: Abortion, Spontaneous; Female; Fetal Death; Humans; Pregnancy; Pregnancy Outcome
PubMed: 25447360
DOI: 10.1016/j.jgyn.2014.09.011 -
Journal of Pediatric Orthopedics Sep 2018Clubfoot is a common congenital anomaly with multiple potential risk factors. Identification of modifiable risk factors may minimize future incidence of clubfoot. The... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Clubfoot is a common congenital anomaly with multiple potential risk factors. Identification of modifiable risk factors may minimize future incidence of clubfoot. The aim of this meta-analysis was to systematically review and analyze the best clinical evidence regarding risk factors associated with clubfoot.
METHODS
Medline, Embase, and Cochrane databases were systematically searched from 1967 to May 11, 2016 for studies reporting risk factors for clubfoot. Randomized trials and observational studies were eligible for inclusion, and assessed in duplicate. Study quality was assessed with the Newcastle-Ottawa Scale or Cochrane risk of bias tool; low quality studies were excluded, all randomized trials were included. Two reviewers extracted data independently. This meta-analysis was conducted in accordance with PRISMA guidelines. Pooled effect estimates for the odds of clubfoot were calculated using random or fixed-effects models based on heterogeneity.
RESULTS
Forty-two studies (28 case-control, 10 cohort, 4 randomized trials) comprising 31,844 clubfoot cases and 6,604,013 controls were included. Risk factors associated with increased odds of clubfoot included maternal smoking [odds ratio (OR)=1.65; 95% confidence interval (CI), 1.54-1.78], paternal smoking (OR=1.72; 95% CI, 1.05-2.84), maternal body mass index >30 (OR=1.46; 95% CI, 1.29-1.65), family history (OR=7.80; 95% CI, 4.04-15.04), amniocentesis (OR=2.08; 95% CI, 1.34-3.21), selective serotonin reuptake inhibitor exposure (OR=1.78; 95% CI, 1.34-2.37) maternal single status (OR=1.17; 95% CI, 1.11-1.23), gestational diabetes (OR=1.40; 95% CI, 1.13-1.72), nulliparity (OR=1.32; 95% CI, 1.19-1.45), male sex (OR=1.68; 95% CI, 1.48-1.94), and aboriginal Australian race (OR=2.35; 95% CI, 1.63-3.38).
CONCLUSIONS
Smoking, maternal obesity, family history, amniocentesis, and some selective serotonin reuptake inhibitor exposures are the most clinically relevant exposures associated with increased odds of clubfoot, with family history representing the greatest risk. Recognition of modifiable risk factors may help in counseling patients, and minimizing clubfoot incidence.
LEVEL OF EVIDENCE
Level II.
Topics: Case-Control Studies; Clubfoot; Cohort Studies; Humans; Observational Studies as Topic; Odds Ratio; Randomized Controlled Trials as Topic; Risk Factors
PubMed: 29917009
DOI: 10.1097/BPO.0000000000001191 -
Obstetrics and Gynecology Nov 2017To systematically review studies reporting the risk of spontaneous abortion among pregnant women of typical reproductive potential with and without uterine leiomyomas. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To systematically review studies reporting the risk of spontaneous abortion among pregnant women of typical reproductive potential with and without uterine leiomyomas.
DATA SOURCES
We searched PubMed, EMBASE, Web of Science, and ClinicalTrials.gov for publications from January 1970 to December 2016.
METHODS OF STUDY SELECTION
We excluded studies that did not use imaging to uniformly document leiomyoma status of all participants, did not have a comparison group without leiomyomas, or primarily included women seeking care for recurrent miscarriage, infertility care, or assisted reproductive technologies.
TABULATION, INTEGRATION, AND RESULTS
Two authors independently reviewed eligibility, extracted data, and assigned overall quality ratings based on predetermined criteria. Of 1,469 articles identified, nine were eligible. Five enrolled general obstetric populations and four included women undergoing amniocentesis. In five studies in general obstetric populations that included 21,829 pregnancies (1,394 women with leiomyomas and 20,435 without), only one adjusted for potential confounders. This meta-analysis revealed no increase in risk of spontaneous abortion among those with leiomyomas compared with those without (11.5% compared with 8.0%; risk ratio 1.16, 95% CI 0.80-1.52). When bias from confounding was estimated for nonadjusted studies, the aggregate calculated risk ratio was 0.83 (95% CI 0.68-0.98).
CONCLUSION
Leiomyoma presence was not associated with increased risk of spontaneous abortion in an analysis of more than 20,000 pregnant women. Failure of prior studies to adjust for confounders may have led to the common clinical belief that leiomyomas are a risk factor for spontaneous abortion.
Topics: Abortion, Habitual; Abortion, Spontaneous; Adult; Female; Humans; Leiomyoma; Pregnancy; Pregnancy Complications, Neoplastic; Risk Factors; Uterine Neoplasms
PubMed: 29016496
DOI: 10.1097/AOG.0000000000002313 -
Ultrasound in Obstetrics & Gynecology :... Jan 2015To estimate procedure-related risks of miscarriage following amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and a... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To estimate procedure-related risks of miscarriage following amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and a meta-analysis.
METHODS
A search of MEDLINE, EMBASE, CINHAL and The Cochrane Library (2000-2014) was performed to review relevant citations reporting procedure-related complications of amniocentesis and CVS. Only studies reporting data on more than 1000 procedures were included in this review to minimize the effect of bias from smaller studies. Heterogeneity between studies was estimated using Cochran's Q, the I(2) statistic and Egger bias. Meta-analysis of proportions was used to derive weighted pooled estimates for the risk of miscarriage before 24 weeks' gestation. Incidence-rate difference meta-analysis was used to estimate pooled procedure-related risks.
RESULTS
The weighted pooled risks of miscarriage following invasive procedures were estimated from analysis of controlled studies including 324 losses in 42 716 women who underwent amniocentesis and 207 losses in 8899 women who underwent CVS. The risk of miscarriage prior to 24 weeks in women who underwent amniocentesis and CVS was 0.81% (95% CI, 0.58-1.08%) and 2.18% (95% CI, 1.61-2.82%), respectively. The background rates of miscarriage in women from the control group that did not undergo any procedures were 0.67% (95% CI, 0.46-0.91%) for amniocentesis and 1.79% (95% CI, 0.61-3.58%) for CVS. The weighted pooled procedure-related risks of miscarriage for amniocentesis and CVS were 0.11% (95% CI, -0.04 to 0.26%) and 0.22% (95% CI, -0.71 to 1.16%), respectively.
CONCLUSION
The procedure-related risks of miscarriage following amniocentesis and CVS are much lower than are currently quoted.
Topics: Abortion, Spontaneous; Amniocentesis; Aneuploidy; Chorionic Villi Sampling; Decision Making; Female; Gestational Age; Humans; Odds Ratio; Patient Education as Topic; Pregnancy; Prenatal Diagnosis; Risk Factors
PubMed: 25042845
DOI: 10.1002/uog.14636 -
PloS One 2020Existing systematic reviews of Rh immunoprophylaxis include only data from randomized controlled trials, have dated searches, and some do not report on all domains of...
BACKGROUND
Existing systematic reviews of Rh immunoprophylaxis include only data from randomized controlled trials, have dated searches, and some do not report on all domains of risk of bias or evaluate the certainty of the evidence. Our objective was to perform an updated review, by including new trials, any comparative observational studies, and assessing the certainty of the evidence using the GRADE framework.
METHODS
We searched MEDLINE, Embase and the Cochrane Library from 2000 to November 26, 2019. Relevant websites and bibliographies of systematic reviews and guidelines were searched for studies published before 2000. Outcomes of interest were sensitization and adverse events. Risk of bias was evaluated with the Cochrane tool and ROBINS-I. The certainty of the evidence was performed using the GRADE framework.
RESULTS
Thirteen randomized trials and eight comparative cohort studies were identified, evaluating 12 comparisons. Although there is some evidence of beneficial treatment effects (e.g., at 6-months postpartum, fewer women who received RhIg at delivery compared to no RhIg became sensitized [70 fewer sensitized women per 1,000 (95%CI: 67 to 71 fewer); I2 = 73%]), due to very low certainty of the evidence, the magnitude of the treatment effect may be overestimated. The certainty of the evidence was very low for most outcomes often due to high risk of bias (e.g., randomization method, allocation concealment, selective reporting) and imprecision (i.e., few events and small sample sizes). There is limited evidence on prophylaxis for invasive fetal procedures (e.g. amniocentesis) in the comparative literature, and few studies reported adverse events.
CONCLUSION
Serious risk of bias and low to very low certainty of the evidence is found in existing RCTs and comparative observational studies addressing optimal effectiveness of Rh immunoprophylaxis. Guideline development committees should exercise caution when assessing the strength of the recommendations that inform and influence clinical practice in this area.
Topics: Female; GRADE Approach; Humans; Immunologic Factors; Postnatal Care; Pregnancy; Prenatal Care; Randomized Controlled Trials as Topic; Rh Isoimmunization; Rh-Hr Blood-Group System
PubMed: 32913362
DOI: 10.1371/journal.pone.0238844