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Archives of Gynecology and Obstetrics Jul 2024In a certain proportion of dichorionic twin pregnancies, the two placentas are fused. The clinical significance of this finding remains unclear. Our objective was to... (Comparative Study)
Comparative Study
PURPOSE
In a certain proportion of dichorionic twin pregnancies, the two placentas are fused. The clinical significance of this finding remains unclear. Our objective was to compare outcomes of dichorionic twin pregnancies with fused versus separate placentas as determined on first-trimester ultrasound.
METHODS
Retrospective study of patients with dichorionic twins followed at a tertiary center between 2014 and 2022. The co-primary outcomes were fetal growth restriction and preeclampsia. Associations between fused placentas and the study outcomes were estimated using multivariable Poisson regression and were reported as adjusted relative risk (aRR) with a 95%-confidence interval (CI).
RESULTS
Of the 328 eligible patients, 175 (53.4%) and 153 (46.6%) had fused and separate placentas, respectively. Compared with pregnancies with separate placentas, patients with fused placentas had a lower risk of preeclampsia [aRR 0.48 (95%-CI 0.24-0.97)] but a higher risk of fetal growth restriction [aRR 1.23 (95%-CI 1.02-1.48)] and admission to the neonatal intensive care unit [aRR 1.31 (95%-CI 1.01-1.71)]. In addition, pregnancies with fused placentas were more likely to have a total placental weight below the 10th percentile than those with separate placentas [aRR 1.93 (95%-CI 1.16-3.21)].
DISCUSSION
Dichorionic twin pregnancies with fused placentas have a lower risk of preeclampsia but are more likely to be complicated by fetal growth restriction, observations that may be attributed to the lower total placentas mass in pregnancies with fused compared with separate placentas. Fused placentas can be used as a potential biomarker for the prediction of pregnancy complications in dichorionic twin pregnancies.
Topics: Humans; Female; Pregnancy; Retrospective Studies; Pregnancy, Twin; Placenta; Adult; Pre-Eclampsia; Fetal Growth Retardation; Twins, Dizygotic; Pregnancy Outcome; Ultrasonography, Prenatal; Pregnancy Trimester, First; Infant, Newborn
PubMed: 38727816
DOI: 10.1007/s00404-024-07548-5 -
Twin Research and Human Genetics : the... Apr 2024TwinsMX registry is a national research initiative in Mexico that aims to understand the complex interplay between genetics and environment in shaping physical and...
TwinsMX registry is a national research initiative in Mexico that aims to understand the complex interplay between genetics and environment in shaping physical and mental health traits among the country's population. With a multidisciplinary approach, TwinsMX aims to advance our knowledge of the genetic and environmental mechanisms underlying ethnic variations in complex traits and diseases, including behavioral, psychometric, anthropometric, metabolic, cardiovascular and mental disorders. With information gathered from over 2800 twins, this article updates the prevalence of several complex traits; and describes the advances and novel ideas we have implemented such as magnetic resonance imaging. The future expansion of the TwinsMX registry will enhance our comprehension of the intricate interplay between genetics and environment in shaping health and disease in the Mexican population. Overall, this report describes the progress in the building of a solid database that will allow the study of complex traits in the Mexican population, valuable not only for our consortium, but also for the worldwide scientific community, by providing new insights of understudied genetically admixed populations.
Topics: Humans; Mexico; Male; Female; Gene-Environment Interaction; Registries; Adult; Diseases in Twins; Middle Aged; Twins, Monozygotic; Twins, Dizygotic; Mental Disorders; Cardiovascular Diseases
PubMed: 38699821
DOI: 10.1017/thg.2024.18 -
BMC Pregnancy and Childbirth May 2024To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived... (Comparative Study)
Comparative Study
Pregnancy outcomes of monochorionic diamniotic and dichorionic diamniotic twin pregnancies conceived by assisted reproductive technology and conceived naturally: a study based on chorionic comparison.
OBJECTIVE
To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived naturally.
METHODS
We retrospectively analyzed the data on twin pregnancies conceived by ART from January 2015 to January 2022,and compared pregnancy outcomes of MCDA and DCDA twins conceived by ART with those of MCDA and DCDA twins conceived naturally, pregnancy outcomes between MCDA and DCDA twins conceived by ART, and pregnancy outcomes of DCT and TCT pregnancies reduced to DCDA pregnancies with those of DCDA pregnancies conceived naturally.
RESULT
MCDA pregnancies conceived by ART accounted for 4.21% of the total pregnancies conceived by ART and 43.81% of the total MCDA pregnancies. DCDA pregnancies conceived by ART accounted for 95.79% of the total pregnancies conceived by ART and 93.26% of the total DCDA pregnancies. Women with MCDA pregnancies conceived by ART had a higher premature delivery rate, lower neonatal weights, a higher placenta previa rate, and a lower twin survival rate than those with MCDA pregnancies conceived naturally (all p < 0.05). Women with DCDA pregnancies conceived naturally had lower rates of preterm birth, higher neonatal weights, and higher twin survival rates than women with DCDA pregnancies conceived by ART and those with DCT and TCT pregnancies reduced to DCDA pregnancies (all p < 0.05).
CONCLUSION
Our study confirms that the pregnancy outcomes of MCDA pregnancies conceived by ART are worse than those of MCDA pregnancies conceived naturally. Similarly, the pregnancy outcomes of naturally-conceived DCDA pregnancies are better than those of DCDA pregnancies conceived by ART and DCT and TCT pregnancies reduced to DCDA pregnancies.
Topics: Humans; Female; Pregnancy; Pregnancy, Twin; Reproductive Techniques, Assisted; Pregnancy Outcome; Retrospective Studies; Adult; Twins, Monozygotic; Chorion; Premature Birth; Twins, Dizygotic; Infant, Newborn; Placenta Previa
PubMed: 38698326
DOI: 10.1186/s12884-024-06521-z -
Ultrasound in Obstetrics & Gynecology :... May 2024
Topics: Humans; Pregnancy; Female; Fetal Growth Retardation; Pregnancy, Twin; Pregnancy Outcome; Twins, Dizygotic; Systematic Reviews as Topic; Meta-Analysis as Topic; Infant, Newborn; Ultrasonography, Prenatal
PubMed: 38695215
DOI: 10.1002/uog.27654 -
Genes Apr 2024The contributions of genetic variation and the environment to gene expression may change across the lifespan. However, few studies have investigated the heritability of...
The contributions of genetic variation and the environment to gene expression may change across the lifespan. However, few studies have investigated the heritability of blood gene expression in older adults. The current study therefore aimed to investigate this question in a community sample of older adults. A total of 246 adults (71 MZ and 52 DZ twins, 69.91% females; mean age-75.79 ± 5.44) were studied. Peripheral blood gene expression was assessed using Illumina microarrays. A heritability analysis was performed using structural equation modelling. There were 5269 probes (19.9%) from 4603 unique genes (23.9%) (total 26,537 probes from 19,256 genes) that were significantly heritable (mean h = 0.40). A pathway analysis of the top 10% of significant genes showed enrichment for the immune response and ageing-associated genes. In a comparison with two other gene expression twin heritability studies using adults from across the lifespan, there were 38 out of 9479 overlapping genes that were significantly heritable. In conclusion, our study found ~24% of the available genes for analysis were heritable in older adults, with only a small number common across studies that used samples from across adulthood, indicating the importance of examining gene expression in older age groups.
Topics: Humans; Female; Aged; Male; Aged, 80 and over; Aging; Twins, Dizygotic; Twins, Monozygotic; Gene Expression
PubMed: 38674429
DOI: 10.3390/genes15040495 -
Prenatal Diagnosis Apr 2024To establish a haplotype-based noninvasive prenatal testing (NIPT) workflow for single-gene recessive disorders that adapt to dizygotic (DZ) twin pregnancies.
OBJECTIVE
To establish a haplotype-based noninvasive prenatal testing (NIPT) workflow for single-gene recessive disorders that adapt to dizygotic (DZ) twin pregnancies.
METHOD
Twin pregnancies at risk of Duchenne muscular dystrophy, Becker muscular dystrophy, hemophilia B, spinal muscular atrophy, phenylketonuria, and nonsyndromic hearing loss were recruited. For subsequent analysis, capture sequencing targeting highly heterozygotic single nucleotide polymorphism sites was conducted. Paternal-specific alleles were used to calculate the total and individual fetal fractions and determine zygosity. A two-step Bayes Factor model was applied to clarify the complex genomic landscape in the maternal plasma: the first step involved determining whether the twins inherited the same haplotype, and the second step involved estimating their individual genotypes. NIPT results were subsequently confirmed by invasive diagnosis.
RESULTS
Nine twin pregnancies were recruited, including five DZ and four monozygotic (MZ) twins. The earliest gestational age was 8 weeks, and the minimum fetal fraction was 4.6%. Three twin pregnancies were reported with one affected fetus, while the remaining six were reported without affected fetuses. Two dichorionic diamniotic twin pregnancies were confirmed to be MZ twins. The NIPT results were 100% consistent with those of invasive procedures or diagnostic genetic testing after birth.
CONCLUSION
This study is the first to perform NIPT for single-gene disorders in twin pregnancies and preliminarily confirm its clinical feasibility. Acknowledging the twins' genotypes in the first trimester is valuable as it empowers obstetric care providers and parents to have adequate time for pregnancy management and decision-making.
PubMed: 38647204
DOI: 10.1002/pd.6565 -
Journal of Neurosurgery. Spine Apr 2024Chiari malformations (CMs) are a group of congenital or acquired disorders characterized by hindbrain overcrowding into an underdeveloped posterior cranial fossa. CM is... (Review)
Review
OBJECTIVE
Chiari malformations (CMs) are a group of congenital or acquired disorders characterized by hindbrain overcrowding into an underdeveloped posterior cranial fossa. CM is considered largely sporadic-however, there exists growing evidence of transmissible genetic underpinnings. The purpose of this systematic review of all familial studies of CM was to investigate the existence of an inherited component and provide recommendations to manage and monitor at-risk family members.
METHODS
This paper includes the following: 1) a unique case report of dizygotic twins who presented at the Toronto Western Hospital Spinal Cord Clinic with symptomatic CM type 1 (CM-1) and syringomyelia; and 2) a systematic review of familial CM. The EMBASE and MEDLINE databases were searched on June 27, 2023, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only articles in the English language concerning the diagnosis of CM in > 1 human family member presented as a case study, case series, or literature review were included.
RESULTS
Among the 29 articles included in the final analysis, a total of 34 families with CM were analyzed. An average of 3 cases of CM were found per family among all generations. Eighty-one cases (88%) reported CM-1, whereas the other 11 (12%) cases reported either CM-0, CM-1.5, or tonsillar ectopia. A syrinx was present in 37 (54%) cases, with 14 (38%) of these patients also reporting a skeletal abnormality, the most common comorbidity. Most family members diagnosed with CM were siblings (18; 35%), followed by monozygotic twins/triplets (12; 23%).
CONCLUSIONS
Patients most often presented with headaches, sensory disturbances, or generalized symptoms. Overall, there exists mounting evidence for a hereditary component of CM. It is unlikely to be explained by a classic mendelian inheritance pattern, but is rather a polygenic architecture influenced by variable penetrance, cosegregation, and entirely nongenetic factors. For first-degree relatives of those affected by CM, the authors' findings may influence clinicians to conduct closer clinical and radiographic monitoring, promote patient education, and consider earlier genetic testing.
PubMed: 38608294
DOI: 10.3171/2024.1.SPINE231277 -
Equine Veterinary Journal Jul 2024Twin gestation in the mare is undesirable and can have disastrous consequences. As in many cases, the key to success in twin management lies in a thorough follow-up and... (Review)
Review
Twin gestation in the mare is undesirable and can have disastrous consequences. As in many cases, the key to success in twin management lies in a thorough follow-up and accurate recording of clinical findings in the pre-breeding examination. A pregnancy diagnosis in the mobility phase is imperative for a good outcome in the event of twin reduction. If a twin gestation is not diagnosed during this early pregnancy stage, several other procedures exist for managing post-fixation twins (>16 days) with varying degrees of success. Most twin pregnancies are the result of multiple ovulations (dizygotic twins). However, monozygotic twins are also sporadically diagnosed, due to the increasing number of transferred in vitro produced equine embryos. In these cases, the most optimal treatment strategy still needs to be determined. This review provides an overview of the various twin reduction techniques described with the expected prognosis as well as of some less reported techniques with their results. In addition, physiological events and the reduction techniques are demonstrated to the user in virtual 3-dimensional illustrations.
Topics: Animals; Female; Pregnancy; Horse Diseases; Horses; Pregnancy Reduction, Multifetal; Pregnancy, Twin; Pregnancy, Animal
PubMed: 38594910
DOI: 10.1111/evj.14094 -
Science Immunology Apr 2024Although human twin studies have revealed the combined contribution of heritable and environmental factors in shaping immune system variability in blood, the...
Although human twin studies have revealed the combined contribution of heritable and environmental factors in shaping immune system variability in blood, the contribution of these factors to immune system variability in tissues remains unexplored. The human uterus undergoes constant regeneration and is exposed to distinct environmental factors. To assess uterine immune system variation, we performed a system-level analysis of endometrial and peripheral blood immune cells in monozygotic twins. Although most immune cell phenotypes in peripheral blood showed high genetic heritability, more variation was found in endometrial immune cells, indicating a stronger influence by environmental factors. Cytomegalovirus infection was identified to influence peripheral blood immune cell variability but had limited effect on endometrial immune cells. Instead, hormonal contraception shaped the local endometrial milieu and immune cell composition with minor influence on the systemic immune system. These results highlight that the magnitude of human immune system variation and factors influencing it can be tissue specific.
Topics: Female; Humans; Twins, Dizygotic; Twins, Monozygotic; Endometrium; Uterus; Immune System
PubMed: 38579017
DOI: 10.1126/sciimmunol.adj7168 -
JAMA Psychiatry Jun 2024
Topics: Humans; Obsessive-Compulsive Disorder; Male; Female; Diseases in Twins; Adult; Twins, Monozygotic; Twins, Dizygotic; Genetic Predisposition to Disease
PubMed: 38568562
DOI: 10.1001/jamapsychiatry.2024.0299