Monoamniotic Twin Pregnancy Research Articles

Monochorionic Monoamniotic Twin Pregnancy: Shared but Not Equal.

Monochorionic Monoamniotic Twin Pregnancy: Shared but Not Equal.

Morphological variations on vital systems in a conjoined twin.

Conjoined twins (CTs), popularly referred to as Siamese twins, are a rare anomaly due to monochorionic and monoamniotic twin pregnancies. Dicephalus dibrachius dipus, a type of parapagus conjoined twin which is characterized by possessing two arms, two legs, a single trunk and two heads, epidemiologically, is an even rarer occurrence of CTs. In this article, a rare, well-preserved anatomical specimen of a dicephalus dibrachius dipus conjoined twin is presented. This study was conducted in a specimen which is part of the collection of the Embryology Museum of the institution by donation and approved by the Research Ethics Committee (REC). The female conjoined twins were born at full-term by cesarean section in the 1970s and died hours after birth. A thorough anatomical description was made through observational analysis, computed tomography and 3D reconstructed images. Major abnormalities were observed in the cardiovascular, respiratory and digestive systems. The internal anatomy exhibited a heart with three atria, two ventricles, two aortic arches, two pulmonary arteries, one innominate venous trunk and a respiratory system with two tracheas and four lungs. No other report was similar to our three atria heart description. This article provides a thorough anatomical description of all systems, which is valuable information for further studies on CTs.

Managing Monoamniotic Twin Pregnancies.

Monoamniotic twins comprise a rare subset of twins at risk of unique and serious complications. In addition to the risks faced by all twins (premature birth, growth restriction), all monochorionic twins (twin-to-twin transfusion syndrome), and all monozygotic twins (congenital anomalies), monoamniotic twins face the unique risk of cord entanglement, in addition to a markedly increased risk of congenital anomalies. Early diagnosis, screening for fetal anomalies and surveillance for twin-twin transfusion syndrome are critical. After fetal viability, frequent fetal monitoring reduces the risk of intrauterine fetal demise.

The management of Monochorionic Monoamniotic (MCMA) twin pregnancy

HIGHLIGHTS Monochorionic monoamniotic (MCMA) twin pregnancy has a significant risk of perinatal morbidity and mortality, including intrauterine fetal death (IUFD). The risk of prematurity, the risk of death due to MCMA complications, the availability of the NICU, also high costs on preterm care were factors in deciding to terminate the pregnancy. The ideal time to deliver monochorionic twins in order to reduce the risks of cord entanglement, growth discrepancies, and intrauterine fetal death is still a point of controversy. Early diagnosis, intensive antenatal monitoring, patient and family decision would contribute to antenatal mortality reduction. ABSTRACT Objectives: To present the management of monochorionic monoamniotic (MCMA) twin pregnancy. Case Report: Advanced prenatal treatment has improved the prognosis for Monochorionic Monoamniotic (MCMA) pregnancies; however, there is still no agreement on how to handle MCMA twins. The authors report 2 cases of monoamniotic monochorionic twin pregnancies. In the first case, a 30-years-old primi pregnant woman detected MCMA at 14 weeks of gestation; no complications related to MCMA were found; she planned delivery at 32 weeks, but one of the babies died in the womb at 31/32 weeks pregnant, a live baby born by cesarean section. The second case was a 36-year-old pregnant woman, on her third pregnancy, diagnosed with MCMA after 12 weeks of pregnancy, no complications related to MCMA, the baby was born at 32 weeks pregnant, and both babies survived. The management was the same in both cases, but different outcomes were obtained; in case 1, the baby died allegedly due to cord entanglement, which could not be detected during pregnancy.

Evaluation of clinical features and outcome of eight fetuses with ectopia cordis; A study from a fetal cardiology center.

We aim to evaluate the clinical course and outcome of cases with a prenatal diagnosis of ectopia cordis in our center. In this retrospective study, we analyzed clinical variables including gestational age at diagnosis, maternal age, associated cardiac, extracardiac, genetic anomalies and, outcome in prenatally diagnosed ectopia cordis cases in our tertiary referral center. Eight ectopia cordis cases from seven pregnancies were included in the study. All fetuses had complete type of ectopia cordis and pentalogy of Cantrell. Five multiple pregnancies were found, four were twin pregnancies (three dichorionic diamniotic, one monochorionic monoamniotic) and one was triplet (trichorionic triamniotic). In the monochorionic monoamniotic twin pregnancy, both fetuses have pentalogy of Cantrell. Two cases had intracardiac structural defects including Tetralogy of Fallot and hypoplastic right heart syndrome. Three pregnancies were terminated, four cases delivered alive could not survive beyond the neonatal period. The striking feature in our study is its association with multiple pregnancies.

Xiphopagic conjoined twins: A case report with pre and postnatal imaging

Siamese or conjoined twins represent a rare but specific malformation occurring in monozygotic and mono-amniotic twin pregnancies. We report a case of xiphopagic conjoined twins and compare the contribution and correlation between ante- and post-mortem imaging for the detailed evaluation of the malformation. Our case highlights the importance of postnatal imaging to better understand this complex type of fetal malformation.

Течение и исходы многоплодной беременности при монохориальной моноамниотической двойне

Aim: to evaluate the course and outcomes of monochorial monoamniotic (MCMA) twin pregnancy. Patients and Methods: this prospective study included 34 patients (a mean age 31.8±4.3 years) with MCMA twins for assessing the course of pregnancy and perinatal outcomes. The authors evaluated such criteria as the timing of delivery and the prenatal management of MCMA-twin pregnancy, as well as the perinatal outcomes and mortality. Monitoring of the pregnant women with umbilical cord entanglement was started at 16 weeks of gestation and included ultrasound examination every two weeks and after 26–28 weeks of gestation — two or three times a week coupled with cardiotocography for fetal assessment. Results: the study demonstrated a high prevalence of cervical insufficiency which was found in 10 (29.4%) MCMA twin pregnancies at 18 to 28 weeks of gestation. The diagnosis of umbilical cord entanglement was established in 16 (47.1%) patients, twin-twin transfusion syndrome (TTTS) – in 2 (5.9%) patients, and twin anemia-polycythemia syndrome (TAPS) – in 1 (2.9%) patient. The reported antenatal losses were 6 of 68 (8.8%) of fetuses. There were 7 perinatal losses of 68 MCMA-twin pregnancies (10.3%). The antenatal and perinatal losses in MCMA twins were caused by the following specific complications: TTTS, cord entanglement and hypoxia due to the selective intrauterine growth restriction (sIUGR). A preterm operative delivery was used in 29 (85.2%) patients with MCMA twins. Five (14.7%) patients did not have complications and it was possible to prolong the pregnancy to 36 weeks. Caesarean sections were carried out almost for all the pregnant women (33 (97.1%)). Conclusion: the antenatal and perinatal losses in MCMA twins are caused by the specific complications. These findings prove that patients with complicated MCMA twin pregnancies need to have a careful monitoring in Level III perinatal centers. Planned caesarean sections are recommended for all MCMA twin pregnancies. If complications are detected, a preterm operative delivery closer to week 35 of gestation will enable to increase the fetal survival rates and thus to improve the perinatal outcomes. Uncomplicated MCMA twin pregnancies can be prolonged to week 36 for improving the condition of newborn babies at the time of delivery. KEYWORDS: multifetal pregnancy, monochorial monoamniotic twin pregnancy, umbilical cord entanglement, neonatal outcome, twin-twin transfusion syndrome, selective intrauterine growth restriction, twin anemia-polycythemia syndrome. FOR CITATION: Kalashnikov S.A., Konoplyannikov A.G., Voskoboeva K.Yu. et al. The course and outcomes of monochorial monoamniotic twin pregnancy. Russian Journal of Woman and Child Health. 2023;6(1):6–12 (in Russ.). DOI: 10.32364/2618-8430-2023-6-1-6-12.

Monochorionic – Monoamniotic Twins’ Placenta

A 33-year-old healthy primigravida with a body mass indexof 21 kg/m², unexplained infertility, pregnancy after IVF, and single embryo transfer, was referred to our department at 12 weeks. We diagnosed monochorionic – monoamniotic twin pregnancy with normal growth, anatomy, and dopplers in both fetuses, anterior normal appearing placenta with eccentric insertion of both umbilical cords, and cervical length of 40 mm. After extensive counseling on the risks and complications of monochorionic – monoamniotic twins, the parents decided to continue with the pregnancy. The course of the pregnancy was uneventful for the mother and fetuses with normal results on all biweekly performed ultrasound examinations. At 30 weeks she received corticosteroids for fetal lung maturation.

Monoamniotic twin pregnancy discordant for body stalk anomaly: a case report

Monoamniotic twin pregnancy discordant for body stalk anomaly: a case report

Monochorionic monoamniotic twin pregnancies.

Monochorionic monoamniotic (MCMA) twin pregnancy is rare and associated with increased complication rates when compared with singletons, dichorionic and monochorionic diamniotic pregnancy in general. Monoamnionicity presents an enormous challenge following its accurate diagnosis, where the absence of an inter-twin membrane subsequently results in cord entanglement and consistently fluctuating foetal position. Furthermore, the detection of twin-twin transfusion syndrome (TTTS) in MCMA pregnancy can be challenging in the absence of amniotic fluid volume discordance without the presence of the inter-twin dividing membrane. Early surveillance of foetal anatomy permits early recognition of foetal structural anomalies, the twin reversed arterial perfusion (TRAP) sequence and conjoined twins. However, the evidence on how best to monitor MCMA pregnancies remains inadequate, though observational studies have demonstrated that once surveillance is initiated, the potential risk of foetal death decreases significantly. In-utero foetal demise can be acute and unpredictable in MCMA pregnancies, despite close surveillance. Elective preterm delivery is usually advocated when the risk of foetal loss upon continuing the pregnancy outweighs the risk of prematurity - around 33 weeks' gestation by caesarean section. Nevertheless, the optimal prenatal surveillance regimen and prompts for delivery have yet to be defined.

CEPHALOTHORACOPHAGUS JANICEP MONOSYMETROS

To report a case of cephalo-thoracophagus janicep monosymmetros. A 30 year old female of child bearing age came to the department of radiology for routine obstetric ultrasonography with gestational age of 30 weeks. Patient had never conceived previously. In the current pregnancy patient had complaints in relation with the pregnancy. Routine ultrasonography was performed to obtain diagnostic output. Radiological evaluation revealed conjoined monochorionic monoamniotic twin pregnancy. Detailed screening revealed fusion of head (cephalophagus) with two sided face of which single eye on one ventral side (cyclops) and two eyes on the dorsal side (Janicep) along with fusion of the thorax (thoracophagus). 'Janicep' is derived from the word Janus, the two faced roman God. The presence of this prototype makes the case report of a rare variety. Cephalothoracophagus janicep monosymmetros has a prevalence 1:50,000 to 1:200,000 with a male:female ratio of 1:3. However post caesarean delivery of the conjoined twin revealed female sex making the case report more rare.

Complicated Monochorionic-Monoamniotic Twin Pregnancy Associated with COVID-19: A Case Report

Coronavirus infection (COVID-19) has quickly emerged as a global pandemic leading to critical health complications. The possibility and risk of vertical transmission of this virus is still unclear, particularly as it relates to pregnant women and their fetuses. Regarding scientific data, there is insufficient research focused on COVID-19 infection complicated with hydrops fetalis and intrauterine fetal demise. In this study, we report an intra uterus fetal death due to hydrops fetalis and twin-to-twin transfusion syndrome (TTTS) in monochorionic–monoamniotic (MCMA) twin pregnancy associated with mild COVID-19 infection in a 33-week-pregnant woman.

Outcomes of Monoamniotic Twin Pregnancies from the First Trimester Onward

Introduction: Monochorionic monoamniotic (MCMA) twins are rare, and information is lacking on pregnancy outcomes from the first trimester onward. This study compares the pregnancy and neonatal outcomes between MCMA and monochorionic diamniotic (MCDA) twin pregnancies from the first trimester onward. We also report on the outcomes of MCMA twin pregnancies continuing after 28 weeks and on the neurodevelopmental outcomes of MCMA twins. Methods: A retrospective single-center cohort study of MCMA and MCDA twin pregnancies followed from the first trimester with a fortnightly ultrasound scan. We excluded pregnancies with a major anomaly diagnosed on the first-trimester ultrasound scan. MCMA twin pregnancies were offered inpatient monitoring from 28 weeks onward, and an elective cesarean section was advised between 32 and 33 weeks. MCDA pregnancies were managed as inpatients only if medically indicated, and an elective birth between 36 and 37 weeks was recommended. Results: We analyzed the outcomes of 52 MCMA and 671 MCDA twin pregnancies. In MCMA twins, the fetal and neonatal survival rate was 81/104 (78%) versus 1,192/1,342 (89%) in MCDA twins (p = 0.016). Double intrauterine demise (IUD) was more common in MA than in DA pairs (13% vs. 3%) (p = 0.002). No IUD occurred in the 40 MCMA pregnancies that continued after 28 weeks, but five women (13%) required an urgent cesarean section for fetal distress. Thirty-eight of 52 eligible infants (73%) underwent a neurodevelopmental assessment. Thirty-three (87%) had cognitive and motor development scores within normal limits. Four infants had mild cognitive or motor impairment, and one infant was diagnosed with spastic diplegia. Conclusion: MCMA twins are associated with decreased survival rates compared to MCDA due to increased rates of double IUD. After 28 weeks, about one in eight women required an urgent delivery for fetal distress. Most infants had normal neurodevelopmental outcomes.

Timing of Delivery for Twins With Growth Discordance and Growth Restriction: An Individual Participant Data Meta-analysis.

First, to evaluate the risks of stillbirth and neonatal death by gestational age in twin pregnancies with different levels of growth discordance and in relation to small for gestational age (SGA), and on this basis to establish optimal gestational ages for delivery. Second, to compare these optimal gestational ages with previously established optimal delivery timing for twin pregnancies not complicated by fetal growth restriction, which, in a previous individual patient meta-analysis, was calculated at 37 0/7 weeks of gestation for dichorionic pregnancies and 36 0/7 weeks for monochorionic pregnancies. A search of MEDLINE, EMBASE, ClinicalTrials.gov, and Ovid between 2015 and 2018 was performed of cohort studies reporting risks of stillbirth and neonatal death in twin pregnancies from 32 to 41 weeks of gestation. Studies from a previous meta-analysis using a similar search strategy (from inception to 2015) were combined. Women with monoamniotic twin pregnancies were excluded. Overall, of 57 eligible studies, 20 cohort studies that contributed original data reporting on 7,474 dichorionic and 2,281 monochorionic twin pairs. We performed an individual participant data meta-analysis to calculate the risk of perinatal death (risk difference between prospective stillbirth and neonatal death) per gestational week. Analyses were stratified by chorionicity, levels of growth discordance, and presence of SGA in one or both twins. For both dichorionic and monochorionic twins, the absolute risks of stillbirth and neonatal death were higher when one or both twins were SGA and increased with greater levels of growth discordance. Regardless of level of growth discordance and birth weight, perinatal risk balanced between 36 0/7-6/7 and 37 0/7-6/7 weeks of gestation in both dichorionic and monochorionic twin pregnancies, with likely higher risk of stillbirth than neonatal death from 37 0/7-6/7 weeks onward. Growth discordance or SGA is associated with higher absolute risks of stillbirth and neonatal death. However, balancing these two risks, we did not find evidence that the optimal timing of delivery is changed by the presence of growth disorders alone. PROSPERO, CRD42018090866.

Excellent perinatal outcome of monoamniotic twin pregnancy with timely diagnosis and optimal management- a retrospective cohort study.

Monoamniotic twins represent a high-risk pregnancy requiring intense follow-up, elective birth and careful consideration of the mode and timing of delivery. We conducted this study to evaluate the perinatal and neonatal outcomes of monoamniotic twin pregnancies in the largest tertiary hospital in Finland. This was a retrospective cohort study including all monoamniotic twin pregnancies during a 17-year period (2002-2018) managed in Helsinki University Hospital. Data on mothers and children were collected from patient files. Chorionicity and amnionicity were defined in first-trimester ultrasound screening. There were altogether 31 monoamniotic twin pregnancies during the study period, including four cases of conjoined twins which all underwent termination of pregnancy, and three miscarriages. In the remaining 24 pregnancies that continued past 24weeks of gestation there was 97.9% survival (one intrauterine death). Three pregnancies were complicated with twin-to-twin transfusion syndrome. All children were delivered by cesarean section with a mean gestational age of 32+5weeks (27+1-34+2weeks). Respiratory distress syndrome (RDS) was observed in 57% (27/47) of neonates and grade I-II intraventricular haemorrhage (IVH) in 6.3% (3/47) of neonates. There were no neonatal deaths and no maternal complications. Monoamniotic twinning is a rare form of pregnancy and carries risks for perinatal and neonatal complications. With timely diagnosis, close monitoring in specialized feto-maternal unit and elective delivery at 32-34weeks the outcome is usually excellent.

Perinatal outcome in monoamniotic twin pregnancies during a 10-year period: a single center, descriptive study

PurposeTo retrospectively investigate perinatal outcome of monoamniotic twin pregnancies in a tertiary center during a 10 year period.MethodsA retrospective analysis of all monoamniotic pregnancies managed at Karolinska University Hospital, Stockholm, Sweden 2010–2019 was performed. The primary outcomes were live birth rate, neonatal death and perinatal survival. The secondary outcomes were late miscarriage, gestational age at delivery and frequency of fetal complications.ResultsTwenty-two monoamniotic pregnancies, with 44 fetuses, were identified. Thirty-five of 44 fetuses (80%) were liveborn. Of 36 fetuses reaching 24 weeks gestation, 35 (97%) were liveborn. There were no neonatal deaths, thus the perinatal survival was 97%. The mean gestational age at birth was 32.5 weeks (SD ± 1.5).ConclusionsThe live birth rate and perinatal survival of monoamniotic pregnancies managed at Karolinska University Hospital was high and comparable to previously published data.

Twin-to-Twin Transfusion Syndrome in monochorionic, monoamniotic twin pregnancy with common umbilical cord insertion.

Twin-to-Twin Transfusion Syndrome in monochorionic, monoamniotic twin pregnancy with common umbilical cord insertion.

Growth Disorders in Twins: An Individual Participant Data Meta-Analysis of Perinatal Mortality

In uncomplicated dichorionic (DC) and monochorionic (MC) twin pregnancies with normally grown fetuses, the optimal time of delivery is 37 and 36 weeks, respectively. The influence of growth discordance on the optimal time of birth, with or without small for gestational age (SGA, < 10th centile), is unknown. We aimed to determine the optimal timing of birth by evaluating the rates of stillbirth (SB) and neonatal death (NND) in women with DC and MC twins with different levels of growth discordance and in relation to SGA. We performed an Individual Participant Data Meta-Analysis of studies reporting rates of SB and NND in women with twin pregnancies from 34-41 weeks (PROSPERO ID: CRD42018090866). Monoamniotic twin pregnancies were excluded. The prospective risk of perinatal death was calculated as the difference between the prospective risk of SB and risk of NND per gestational week. Analyses were stratified by chorionicity, different intervals of growth discordance and presence of SGA in one or both twins. We did not analyse data about associated obstetric complications or abnormal ultrasound findings. We included 20 studies reporting on 7474 women with DC and 2281 women with MC twin pairs. For both DC and MC twins the absolute risks of SB and NND were higher when one or both twins were SGA and increased with greater levels of growth discordance. Regardless of level of growth discordance or presence of SGA, women with DC and MC twins had higher risk of SB than NND from 37 weeks onwards (Fig. 1, Fig. 2). For MC twins, the nadir was between 36-37 weeks. The nadir for perinatal mortality risk for women with DC twins with growth discordance or SGA is around 37 weeks. For MC twins this is between 36-37 weeks, favouring delivery from 37 weeks onward. Growth discordance or SGA is associated with higher absolute SB and neonatal risks but does not largely influence the optimal timing of birth.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Complications Associated With a Monocorial Twin Pregnancy Monoamniotic.

A case report of a monoamniotic monochorionic twin pregnancy is presented and a literature review of its associated complications is carried out. A literature search was carried out in databases such as Medline / Pubmed, selecting articles published in Spanish and English during the period from January 1990 to May 2013. The terms “twins”, “monozygotic twins”, “ multiple pregnancy”, “twin pregnancy”. Review articles and cross-sectional studies were included. Monoamniotic monochorial twin gestation is a rare event. This condition is associated with multiple obstetric complications including fetal death related to umbilical cord accidents (crossovers). The objective of prenatal care is the prevention of fetal mortality, so continuous testing of fetal well-being is suggested. Termination of pregnancy in the 34th week of gestation by caesarean section, after administration of steroids, has been proposed.

Antenatal Diagnosis of Parapagus Conjoined Twins: 3D Virtual and 3D Physical Models.

Conjoined twins (CTs) are a rare complication from monochorionic and monoamniotic twin pregnancies. We describe the use of 3D technologies, including 3D virtual and 3D physical models on prenatal evaluation of one parapagus CT. A 16-year-old G1P0 woman was referred for fetal magnetic resonance imaging (MRI) anatomical evaluation of a CT at 28 weeks of gestation. 3D images of the fetal surface were generated by the software during the examination for spatial comprehension of the relationship between the fetal parts. The pair of CTs died at the 32nd week of gestation, a few hours after cesarean section. 3D technologies are an important tool for parental counseling and preparation of the multidisciplinary care team for delivery and neonatal assistance and possible surgical planning for postnatal separation in CTs cases.