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Fetal Diagnosis and Therapy 2017Multiple pregnancies have tripled in the United States over the past 3 decades. Attributed to increasing maternal age at delivery but more so assisted reproductive... (Review)
Review
BACKGROUND/OBJECTIVES
Multiple pregnancies have tripled in the United States over the past 3 decades. Attributed to increasing maternal age at delivery but more so assisted reproductive technological advances, an effort has been made to decrease twinning through elective single embryo transfer. We sought to review and evaluate risks of monochorionic twinning as a predictable consequence of increasing utilization of elective single embryo transfer on perinatal outcomes. Primary outcomes included twinning rates, fetal anomalies, growth, preterm birth, and mortality. Secondary outcomes included neurological and pulmonary disability, intrauterine growth restriction, and congenital cardiac anomalies and twin-twin transfusion syndrome.
DATA SOURCES
PubMed and Embase.
RESULTS
A total of 106 studies identified by systematic search met the inclusion criteria. The trend for lower numbers of embryos transferred has inadvertently led to an increase in monochorionic twinning. This is associated with worse outcomes compared to dichorionic twinning and singleton gestations for all outcomes studied.
DISCUSSION
Of great concern for monochorionic twins is the risk profile of significant morbidity and mortality. Transfer of 2 embryos should be considered to avoid higher risks inherent to the shared placental phenomena related to monochorionic twins.
Topics: Female; Fetal Diseases; Humans; Infant, Premature; Pregnancy; Pregnancy Outcome; Pregnancy, Twin; Premature Birth; Single Embryo Transfer; Twins, Monozygotic
PubMed: 28351027
DOI: 10.1159/000464286 -
Otology & Neurotology : Official... Feb 2023Congenital cytomegalovirus infection is the leading nonhereditary cause of pediatric sensorineural hearing loss. This systematic review evaluated infection concordance...
OBJECTIVE
Congenital cytomegalovirus infection is the leading nonhereditary cause of pediatric sensorineural hearing loss. This systematic review evaluated infection concordance and comparative hearing abilities in twins/multiple births to model infection patterns.
DATABASES REVIEWED
PubMed, Embase, Web of Science, and Google Scholar.
METHODS
Studies that reported hearing outcomes of congenital cytomegalovirus infection in at least one multiple birth were eligible. Concordant infections (both twins) and discordant infections (single twin) were included. Multiple reviewers performed data extraction and quality assessment. Analyses involved relative risk of infection concordance by zygosity and chorionicity and odds of hearing loss by infection concordance. Hearing outcomes were compared between siblings.
RESULTS
Of 247 studies screened, 31 were included (74.2% high quality). The review captured 40 eligible multiple births. Among infected patients, 42.9% (95% confidence interval, 31.2-55.2%) demonstrated hearing loss. All uninfected twins had normal hearing. Most infections were concordant, and infected patients experienced 4.11 (1.18-14.36) times greater odds of hearing loss if their twin was also infected ( p = .02). Yet siblings' hearing outcomes diverged in over 40% of concordant cases. If either twin is infected, infection risk in the second twin is 3.25 (1.83-5.79) times greater in monozygotic than dizygotic twins and 2.50 (1.61-3.88) times greater in monochorionic than dichorionic twins (both p < .001). We describe a case from our practice.
CONCLUSION
Congenital cytomegalovirus infection patterns and hearing outcomes can vary widely even within a shared fetal and postnatal environment. Suspected infection in a twin indicates that both should receive testing and continued monitoring for late-onset sequelae.
Topics: Pregnancy; Female; Humans; Child; Pregnancy, Multiple; Twins, Dizygotic; Cytomegalovirus Infections; Hearing
PubMed: 36538753
DOI: 10.1097/MAO.0000000000003776 -
The Journal of Maternal-fetal &... Jul 2020Velamentous cord insertion (VCI) has been proposed to be associated with some specific complications among monochorionic (MC) twin pregnancies. This meta-analysis and... (Meta-Analysis)
Meta-Analysis
Velamentous cord insertion (VCI) has been proposed to be associated with some specific complications among monochorionic (MC) twin pregnancies. This meta-analysis and systematic review aims to determine the role of VCI in MC twin pregnancies. The PubMed, Embase and Web of Science databases and reference lists were searched for relevant studies. Outcomes of interest included twin-to-twin transfusion syndrome (TTTS), birthweight discordance (BWD) and selective intrauterine growth restriction (sIUGR). The methodological quality of the included studies was assessed by using the Newcastle-Ottawa Scale. The pooled results were calculated by means of a random or fixed effect model to obtain odds ratio with 95% confidential interval (CI). Subgroup analyses were utilized to detect the sources of heterogeneity. Twenty studies were eligible for inclusion. The pooled result suggested a significant association between VCI and TTTS (OR, 1.542; 95% CI, 1.116-2.129) with a moderate level of heterogeneity ( test: = .024; = 50.2%). Subgroup analysis reported single-center study, methodological quality and exclusion of laser-coagulated TTTS as the sources of heterogeneity. Another analysis revealed an increased risk of BWD among twin pregnancies with VCI (OR, 2.945; 95% CI, 2.176-3.984) with a low heterogeneity ( test: = .347; = 10.5%). None of study level characteristics was found to be an influencing factor. Three studies reporting on sIUGR suggested a significant association between VCI and sIUGR. The meta-analysis and systematic review suggests an association between VCI and BWD and sIUGR. However, the association between VCI and TTTS may be overestimated and high-quality studies with a representative sample are needed in further research.
Topics: Birth Weight; Female; Fetal Growth Retardation; Fetofetal Transfusion; Humans; Observational Studies as Topic; Pregnancy; Pregnancy, Twin; Twins, Monozygotic; Umbilical Cord
PubMed: 30458694
DOI: 10.1080/14767058.2018.1551350 -
Cornea Dec 2022The objective of this study was to undertake a systematic review of the literature reporting on clinical registries in dry eye disease (DED).
PURPOSE
The objective of this study was to undertake a systematic review of the literature reporting on clinical registries in dry eye disease (DED).
METHODS
Electronic searches were conducted using systematic review methodology to provide an overview of clinical registries in ophthalmology and to identify clinical registries reporting on dry eye parameters. Two reviewers independently assessed titles and abstracts, then full-texts for eligibility.
RESULTS
A total of 129 clinical registries in ophthalmology were identified. The most common conditions captured were blindness or low vision, followed by glaucoma and corneal transplantation. Most of the registries originated in Europe (n = 56), followed by North America (n = 28). Of the registries identified, 12 were multinational, 59 were national, and 17 were regional. The second search identified 27 eligible articles, from which 8 clinical registries reporting on dry eye parameters were identified. One registry included patients with a diagnosis of dry eye. The remaining 7 registries included patients from a nationwide administrative ophthalmic database (n = 1), Sjögren syndrome (n = 4), glaucoma (n = 1), or were monozygotic and dizygotic twins (n = 1), who were evaluated for DED. Five of the registries were actively collecting data.
CONCLUSIONS
Most of the registries identified in this review evaluated aqueous deficient dry eye; however, the most common type of dry eye in the general population is evaporative. Few registries also collected recommended dry eye clinical assessment. A well-designed clinical registry for DED that engages international eye care clinicians has the potential to vastly contribute to addressing pivotal gaps in understanding this highly prevalent disease.
Topics: Humans; Dry Eye Syndromes; Registries; Ophthalmology; Databases, Factual; Glaucoma
PubMed: 36197325
DOI: 10.1097/ICO.0000000000003139 -
Ultrasound in Obstetrics & Gynecology :... Feb 2019To quantify the rate of perinatal mortality in monochorionic monoamniotic (MCMA) twin pregnancies, according to gestational age, and to ascertain the incidence of... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To quantify the rate of perinatal mortality in monochorionic monoamniotic (MCMA) twin pregnancies, according to gestational age, and to ascertain the incidence of mortality in pregnancies managed as inpatients compared with those managed as outpatients.
METHODS
MEDLINE, EMBASE and CINAHL databases were searched for studies on monoamniotic twin pregnancy. The primary outcomes explored were the incidence of intrauterine death (IUD), neonatal death (NND) and perinatal death (PND) in MCMA twins at different gestational-age windows (24-30, 31-32, 33-34, 35-36 and ≥ 37 weeks of gestation). The secondary outcomes were the incidence of IUD, NND and PND in MCMA twins according to the type of fetal monitoring (inpatient vs outpatient), and the incidence of delivery ahead of schedule. Random-effects model meta-analyses were used to analyze the data.
RESULTS
Twenty-five studies (1628 non-anomalous twins reaching 24 weeks of gestation) were included. Single and double intrauterine deaths occurred in 2.5% (95% CI, 1.8-3.3%) and 3.8% (95% CI, 2.5-5.3%) of cases, respectively. IUD occurred in 4.3% (95% CI, 2.8-6.2%) of twins at 24-30 weeks, in 1.0% (95% CI, 0.6-1.7%) at 31-32 weeks and in 2.2% (95% CI, 0.9-3.9%) at 33-34 weeks of gestation, while there was no case of IUD, either single or double, from 35 weeks of gestation. In MCMA twin pregnancies managed mainly as inpatients, the incidence of IUD was 3.0% (95% CI, 1.4-5.2%), while the corresponding figure for those managed mainly as outpatients was 7.4% (95% CI, 4.4-11.1%). Finally, 37.8% (95% CI, 28.0-48.2%) of MCMA pregnancies were delivered before the scheduled time, due mainly to spontaneous preterm labor or abnormal cardiotocographic findings.
CONCLUSIONS
MCMA twins are at high risk of perinatal loss during the third trimester of pregnancy, with the large majority of such losses occurring as apparently unexpected events. Inpatient management seems to be associated with a lower rate of mortality, although further studies are needed in order to establish the appropriate type and timing of prenatal assessment in these pregnancies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Female; Gestational Age; Humans; Infant, Newborn; Perinatal Care; Perinatal Mortality; Pregnancy; Pregnancy, Twin; Premature Birth; Retrospective Studies; Time Factors; Twins, Monozygotic
PubMed: 30125418
DOI: 10.1002/uog.20100 -
Intervention versus a conservative approach in the management of TRAP sequence: a systematic review.Journal of Perinatal Medicine Aug 2016In the management of twin reversed arterial perfusion (TRAP) sequence, we wished to (i) determine if intervention is better than a conservative approach and (ii) assess... (Comparative Study)
Comparative Study Review
OBJECTIVE
In the management of twin reversed arterial perfusion (TRAP) sequence, we wished to (i) determine if intervention is better than a conservative approach and (ii) assess if any of the apparent adverse prognostic indicators could guide intervention.
METHODS
A systematic review was conducted between 1994 and 2014. Data extracted were inspected for heterogeneity. Overall rates and confidence intervals (CIs) for each prognostic factor were calculated. Where there were comparative data, the odds ratio (OR) was calculated.
RESULTS
Twenty-six studies were included in the review. When all cases were considered, intervention either by cord occlusion or by ablation conferred a better survival rate compared with conservative management (OR=2.22, 95% CI 1.23-4.01, heterogeneity I2=37%, P=0.008). This difference was greater in the presence of one or more poor prognostic features (OR=8.58, 95% CI 1.47-49.96, heterogeneity I2=0%, P=0.02). Survival was better using ablative techniques compared to cord occlusion (OR=9.84, 95% CI 1.56-62.00, heterogeneity I2=0%, P=0.01).
CONCLUSION
Intervention either by cord occlusion or by ablation confers a better survival rate compared to conservative management. This appears more compelling if there are one or more poor prognostic features. Ablative techniques are superior to cord occlusion. There were insufficient data to determine which poor prognostic features should guide management.
Topics: Ablation Techniques; Diseases in Twins; Embolization, Therapeutic; Fetal Heart; Fetal Therapies; Heart Defects, Congenital; Humans; Prognosis; Twins, Monozygotic
PubMed: 26356357
DOI: 10.1515/jpm-2015-0165 -
Ultrasound in Obstetrics & Gynecology :... Jan 2019To explore the impact of severity and management (expectant, laser treatment or selective reduction) on perinatal outcome of monochorionic twin pregnancies complicated... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To explore the impact of severity and management (expectant, laser treatment or selective reduction) on perinatal outcome of monochorionic twin pregnancies complicated by selective fetal growth restriction (sFGR).
METHODS
MEDLINE, EMBASE, CINAHL, ClinicalTrials.gov and The Cochrane Library databases were searched for studies on outcome following expectant management, laser treatment or selective reduction in monochorionic twin pregnancies complicated by sFGR. Only pregnancies affected by sFGR and categorized according to the Gratacós classification (Type I, II or III) were included. The primary outcome was mortality, including single and double intrauterine (IUD), neonatal (NND) and perinatal deaths. Secondary outcomes were neonatal morbidity, abnormal postnatal brain imaging, intraventricular hemorrhage, periventricular leukomalacia, respiratory distress syndrome, admission to neonatal intensive care unit and survival free from neurological complications (intact survival). Meta-analyses of proportions were used to analyze the extracted data according to management, severity of sFGR and fetal size (smaller vs larger twin).
RESULTS
Sixteen observational studies (786 monochorionic twin pregnancies) were included. In pregnancies complicated by Type-I sFGR managed expectantly, IUD occurred in 3.1% (95% CI, 1.1-5.9%) of fetuses and 97.9% (95% CI, 93.6-99.9%) of twins had intact survival. In pregnancies complicated by Type-I sFGR treated using laser therapy, IUD occurred in 16.7% (95% CI, 0.4-64.1%) of fetuses and, in those treated using selective reduction, IUD occurred in 0% (95% CI, 0-34.9%) of cotwins, with no evidence of neurological complications in the survivors. In pregnancies complicated by Type-II sFGR managed expectantly, IUD occurred in 16.6% (95% CI, 6.9-29.5%) and NND in 6.4% (95% CI, 0.2-28.2%) of fetuses, and 89.3% (95% CI, 71.8-97.7%) of twins survived without neurological compromise. In Type-II sFGR pregnancies treated using laser therapy, IUD occurred in 44.3% (95% CI, 22.2-67.7%) of fetuses, while none of the affected cases experienced morbidity and survivors were free of neurological complications. Of pregnancies undergoing selective reduction, IUD of the cotwin occurred in 5.0% (95% CI, 0.03-20.5%) and NND in 3.7% (95% CI, 0.2-11.1%), and 90.6% (95% CI, 42.3-94.3%) of surviving cotwins were free from neurological complications. In pregnancies complicated by Type-III sFGR managed expectantly, IUD occurred in 13.2% (95% CI, 7.2-20.5%) and NND in 6.8% (95% CI, 0.7-18.6%) of fetuses, and 61.9% (95% CI, 38.4-81.9%) of twins had intact survival. In pregnancies complicated by Type-III sFGR treated with laser therapy, IUD occurred in 32.9% (95% CI, 20.9-46.2%) of fetuses and all surviving twins were without neurological complications. Finally, in pregnancies with Type-III sFGR treated with selective reduction, NND occurred in 5.2% (95% CI, 0.8-12.8%) of cotwins and 98.8% (95% CI, 93.9-99.9%) had intact survival.
CONCLUSION
Type-I sFGR is characterized by good perinatal outcome when managed expectantly, which represents the most reasonable management strategy for the large majority of affected cases. Pregnancies complicated by Type-II or -III sFGR treated with fetoscopic laser ablation have a higher rate of mortality but lower rate of morbidity compared with those managed expectantly, supporting the use of fetal therapy at gestations remote from neonatal viability. Data on outcome following selective reduction are scarce. In view of the lack of evidence from randomized controlled trials, prenatal management of sFGR should be individualized according to gestational age at diagnosis, severity of growth discordance and magnitude of Doppler anomalies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Female; Fetal Growth Retardation; Humans; Infant, Newborn; Perinatal Mortality; Pregnancy; Pregnancy Outcome; Pregnancy, Twin; Twins, Monozygotic
PubMed: 30207011
DOI: 10.1002/uog.20114 -
Ultrasound in Obstetrics & Gynecology :... May 2020Selective fetal growth restriction (sFGR) occurs in monochorionic twin pregnancies when unequal placental sharing leads to restriction in the growth of just one twin....
OBJECTIVE
Selective fetal growth restriction (sFGR) occurs in monochorionic twin pregnancies when unequal placental sharing leads to restriction in the growth of just one twin. Management options include laser separation of the fetal circulations, selective reduction or expectant management, but what constitutes the best treatment is not yet known. New trials in this area are urgently needed but, in this rare and complex group, maximizing the relevance and utility of clinical research design and outputs is paramount. A core outcome set ensures standardized outcome collection and reporting in future research. The objective of this study was to develop a core outcome set for studies evaluating treatments for sFGR in monochorionic twins.
METHODS
An international steering group of clinicians, researchers and patients with experience of sFGR was established to oversee the process of development of a core outcome set for studies investigating the management of sFGR. Outcomes reported in the literature were identified through a systematic review and informed the design of a three-round Delphi survey. Clinicians, researchers, and patients and family representatives participated in the survey. Outcomes were scored on a Likert scale from 1 (limited importance for making a decision) to 9 (critical for making a decision). Consensus was defined a priori as a Likert score of ≥ 8 in the third round of the Delphi survey. Participants were then invited to take part in an international meeting of stakeholders in which the modified nominal group technique was used to consider the consensus outcomes and agree on a final core outcome set.
RESULTS
Ninety-six outcomes were identified from 39 studies in the systematic review. One hundred and three participants from 23 countries completed the first round of the Delphi survey, of whom 88 completed all three rounds. Twenty-nine outcomes met the a priori criteria for consensus and, along with six additional outcomes, were prioritized in a consensus development meeting, using the modified nominal group technique. Twenty-five stakeholders participated in this meeting, including researchers (n = 3), fetal medicine specialists (n = 3), obstetricians (n = 2), neonatologists (n = 3), midwives (n = 4), parents and family members (n = 6), patient group representatives (n = 3), and a sonographer. Eleven core outcomes were agreed upon. These were live birth, gestational age at birth, birth weight, intertwin birth-weight discordance, death of surviving twin after death of cotwin, loss during pregnancy or before final hospital discharge, parental stress, procedure-related adverse maternal outcome, length of neonatal stay in hospital, neurological abnormality on postnatal imaging and childhood disability.
CONCLUSIONS
This core outcome set for studies investigating the management of sFGR represents the consensus of a large and diverse group of international collaborators. Use of these outcomes in future trials should help to increase the clinical relevance of research on this condition. Consensus agreement on core outcome definitions and measures is now required. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Birth Weight; Consensus; Delphi Technique; Endpoint Determination; Female; Fetal Growth Retardation; Gestational Age; Humans; Infant, Newborn; Live Birth; Obstetric Surgical Procedures; Outcome Assessment, Health Care; Pregnancy; Pregnancy, Twin; Treatment Outcome; Twins, Monozygotic
PubMed: 31273879
DOI: 10.1002/uog.20388 -
Prenatal Diagnosis Aug 2022This systematic review aims to assess the gestational age at birth and perinatal outcome [intrauterine demise (IUD), neonatal mortality and severe cerebral injury] in... (Review)
Review
This systematic review aims to assess the gestational age at birth and perinatal outcome [intrauterine demise (IUD), neonatal mortality and severe cerebral injury] in monochorionic twins with selective fetal growth restriction (sFGR), according to Gratacós classification based on umbilical artery Doppler flow patterns in the smaller twin. Seventeen articles were included. Gestational age at birth varied from 33.0 to 36.0 weeks in type I, 27.6-32.4 weeks in type II, and 28.3-33.8 weeks in type III. IUD rate differed from 0%-4% in type I to 0%-40% in type II and 0%-23% in type III. Neonatal mortality rate was between 0%-10% in type I, 0%-38% in type II, and 0%-17% in type III. Cerebral injury was present in 0%-2% of type I, 2%-30% of type II and 0%-33% of type III cases. The timing of delivery in sFGR varied substantially among studies, particularly in type II and III. The quality of evidence was moderate due to heterogenous study populations with varying definitions of sFGR and perinatal outcome parameters, as well as a lack of consensus on the use of the Gratacós classification, leading to substantial incomparability. Our review identifies the urgent need for uniform antenatal diagnostic criteria and definitions of outcome parameters.
Topics: Diseases in Twins; Female; Fetal Growth Retardation; Gestational Age; Humans; Infant, Newborn; Pregnancy; Pregnancy, Twin; Retrospective Studies; Twins, Monozygotic; Ultrasonography, Prenatal; Umbilical Arteries
PubMed: 35808908
DOI: 10.1002/pd.6206 -
Prenatal Diagnosis May 2023Selective fetal growth restriction (sFGR) complicates 10%-26% of monochorionic twins. Treatment options include cord coagulation, expectant management, and fetoscopic... (Review)
Review
Selective fetal growth restriction (sFGR) complicates 10%-26% of monochorionic twins. Treatment options include cord coagulation, expectant management, and fetoscopic laser photocoagulation. This review compared laser to expectant management for situations when cord coagulation is not an option. The MEDLINE, EMBASE, and Cochrane databases were queried for studies that compared laser to expectant management for sFGR. GRADE was used to assess quality prior to meta-analysis. A random-effects model was used to generate relative risks. Six studies were included, encompassing 299 pregnancies. One study was randomized and the remainder were retrospective cohorts. Laser is associated with more fetal deaths of the FGR twin compared to expectant management (risk ratio [RR] 2.5, 95% confidence interval [CI] 1.43-4.37, p = 0.001, I2 = 48%). Neonatal deaths and gestational age at delivery did not differ. Laser was associated with decreased abnormal neuroimaging in the AGA twin (RR 0.25, 95% CI 0.07-0.97, p = 0.05). Neurodevelopmental outcomes did not differ, although these data are limited. Laser causes more fetal deaths of the FGR twin without altering gestational age at delivery or rates of neonatal death. The literature is heterogeneous and the level of bias is high. Randomized trials that address laser for type II sFGR are needed and should include long-term neurological outcomes.
Topics: Female; Humans; Infant, Newborn; Pregnancy; Fetal Death; Fetal Growth Retardation; Gestational Age; Laser Therapy; Perinatal Death; Pregnancy, Twin; Retrospective Studies; Twins, Monozygotic; Watchful Waiting
PubMed: 36991554
DOI: 10.1002/pd.6348