Monoamniotic Research Articles

Cord occlusion in twin reversed arterial perfusion sequence: a retrospective study of laser photocoagulation vs radiofrequency ablation.

Twin reversed arterial perfusion (TRAP) sequence is a rare condition complicating monozygotic multiple gestations. Prenatal management via umbilical cord occlusion (UCO) of the anomalous twin has been shown to improve pump twin survival. We compared outcomes of gestations with high-risk TRAP sequence treated with mid-trimester UCO using laser photocoagulation vs radiofrequency ablation (RFA). This is a retrospective, single-center, cohort study of all patients with high-risk TRAP sequence who underwent UCO from 2006-2023. High-risk criteria were defined as follows: larger abdominal circumference of the anomalous twin, polyhydramnios, critically abnormal Doppler waveforms in the pump twin, hydrops in the pump twin, and/or monoamniotic twins. The primary outcome was 30-day survival of the pump twin. The 74 patients were divided equally between the laser and RFA groups. For the 2 groups, mean gestational age (GA) at UCO (20.5 ± 2.3 vs 20.7 ± 3.1 weeks, P=.987) and mean GA at delivery (35.2 ± 4.6 vs 34.5 ± 5.7 weeks, P=.812) were similar. The 30-day neonatal survival rate did not differ (91.9% [34/37] vs 89.2% [33/37], OR: 1.37 [0.29-6.61], P=.692). No difference in 30-day neonatal survival was identified in patients with high-risk TRAP sequence who underwent mid-trimester UCO by laser vs RFA.

Co-Twin Prognosis After Single Intrauterine Fetal Death at a Tertiary Care Hospital in India: A Retrospective Observational Study.

Twin pregnancy is associated with an increased risk of perinatal morbidity. Besides, if intrauterine death of a single twin occurs, it increases the morbidity of the surviving co-twin perinatally and postnatally. The objective of this study was to determine the incidence of single intrauterine fetal death (SIUFD) in a twin pregnancy and fetal outcome defined in dimensions according to the complications in the surviving co-twin. Data on twin pregnancies were collected retrospectively for a period of five years (from 2015 to 2019) from the labour room records of the Central Records Department (CRD) at the Postgraduate Institute of Medical Education and Research, Chandigarh, India. Cases with SIUFD were studied individually and neonatal follow-up was taken post delivery for up to three to eight years. Inclusion criteria were SIUFD in twin pregnancies after 14 weeks gestation, chorionicity pre-defined by early trimester ultrasonography. Exclusion criteria were higher-order pregnancy and monoamniotic twins. A total of1246 (4.273%) twin deliveries were conducted in the study period. Of these, 107 (8.587%) pregnancies had SIUFD with co-twin surviving in utero. Among these, 77 (72%) were dichorionic diamniotic (DCDA) twin pregnancies and 30 (28%) were monochorionic diamniotic (MCDA) twin pregnancies. The incidence of SIUFDwas 8.5%. Preterm birth was the most common complication observed in our study and was found in 53.5% and 58.3% of participants in DCDA and MCDA twins, respectively. Early neonatal death (within 24 hours of life) of the surviving twin was found in 29.2% monochorionic twins with SIUFD. SIUFD at < 28 weeks gestation led to a greater number of early neonatal deaths of surviving twins. The incidence of neurodevelopmental disorders (cerebral palsy, developmental delay, epilepsy) in our population after birth was 7.5% (n=93). Twin pregnancies with SIUFD have an increased incidence of preterm labour, increased neonatal death of the surviving twin, and neurodevelopmental disorders (cerebral palsy, developmental delay, epilepsy). Monochorionicity and SIUFD at <28 weeks gestation are associated with increased neonatal deaths in co-twin. The Incidence of neurodevelopmental disorders is not directly associated with chorionicity, but developmental delay is more profoundly seen in the monochorionic group.

PP-010 A Case of monochorionic monoamniotic twins with cord entanglement and its outcome

PP-010 A Case of monochorionic monoamniotic twins with cord entanglement and its outcome

True Umbilical Cord Knot without Adverse Perinatal Outcome: A Brief Review

True umbilical cord knots are not a common occurrence, however when they do present, it is ironic that despite having availability of antenatal ultrasound, they are not diagnosed antenatally most of the time, due to cord length and loops of cord making visibility poor. However with 4 dimension ultrasound and serial doppler study there can be better pick up rate. There is controversy around risks with true knots and cases of meconium stained liquor, low Apgar scores, hypoxic ischemic encephalopathy, other neonatal complications necessitating neonatal intensive care unit admission and fetal still birth have been reported. The umbilical cord attaches to the placenta and transfers blood, oxygen and nutrition to the fetus. A true umbilical cord knot happens when the cord loops over itself with fetal movements, a tight knot can impair the fetal circulation and lead to fetal hypoxia. In such a situation, fetal surveillance shows sub optimal cardiotocograph tracing, and when the patient is taken for emergency cesarian section, a tight umbilical cord knot is seen, which was causing fetal hypoxia. Certain conditions are more predisposed for true knots such as polyhydramnios, longer length of the cord, smaller than average size fetus, monoamniotic twins and multiparity. Our case report presents a true umbilical cord at an elective cesarian section in a primigravida. The patient had an uneventful pregnancy with regular fetal surveillance through ultrasound and doppler scans and fetal heart tracing. An elective cesarian section was performed at 38 weeks at patient’s request and at the time a nuchal cord and true umbilical cord was noted.

Early diagnosis and management of inseparable conjoint twins. A low-middle-income country experience

HIGHLIGHTS Conjoined twins have captivated mankind for centuries due to the rarity of this birth type; nonetheless, physicians have constantly encountered difficulties in dealing with conjoined twins. Early diagnosis of conjoined twins during prenatal examination is critical for ascertaining the prognosis of the fetus, guiding parental counseling over appropriate courses of action, and potentially enabling the termination of the pregnancy. First-trimester ultrasonography and MRI are complementary modalities in determining the diagnosis and prognosis of conjoined twins in early pregnancy. ABSTRACT Objectives: To discuss the crucial early diagnosis of conjoined twins to determine the type and prognosis. Case Report: A 27-year-old woman was referred to the type A referral hospital with suspicion of congenital abnormalities at 17 weeks of pregnancy. Ultrasound results showed intrauterine monochorionic monoamniotic twins with babies fused on their heads to the urogenital part. The MRI showed a craniopagus, suspected meningomyelocele, and severe bilateral hydronephrosis in the second baby. Due to non-separable cases and a bad prognosis for the fetus, the pregnancy was terminated using misoprostol induction and inserting a balloon catheter. The fetus is born weighing 400 g and 20 cm in length. Conjoined twins obtained the rostral type: a fused head with two faces, a fused thorax until the lower abdomen with one umbilicus, and two pairs of hands and feet. The diagnosis of conjoint twins becomes a problem in early pregnancy, mostly in developing countries. Early diagnosis of conjoined twins during prenatal examination is critical for ascertaining the prognosis of the fetus, guiding parental counseling over appropriate courses of action, and potentially enabling the termination of the pregnancy to prevent maternal stress and complications. Conclusion: Conjoined twins should be identified as soon as feasible to establish the best course of management for both mother and fetus. Ultrasonography and MRI are modalities for determining the diagnosis and prognosis of conjoined twins.

Twin reverse arterial perfusion sequence

Twin Reverse Arterial Perfusion Sequence (TRAP) is a rare condition specific to identical twins. Overall, TRAP affects around 1% of all monozygotic twins, with 75% occurring in monochorionic-biamniotic twins and the remaining 25% in monoamniotic twins. TRAP is characterized by a normal-appearing pump twin supporting a dysmorphic acardiac twin through aberrant arterio-arterial anastomoses in the shared single placenta.

Monochorionic Monoamniotic Twin Pregnancy: Shared but Not Equal.

Monochorionic Monoamniotic Twin Pregnancy: Shared but Not Equal.

Knots of the umbilical cord: Incidence, diagnosis, and management.

Knot(s) of the umbilical cord have received emphasis because the clinical assessments and sonographic literature show a crucial role in fetal outcomes. The true umbilical cord knot could be a knot in a singleton pregnancy or an entanglement of two umbilical cords in monoamniotic twins. Clinical manifestations are almost silent, which can raise clinical challenges. They worsen outcomes, and the pathology can be easily missed during prenatal visits because ultrasonographers do not pay attention to the cord during an obstetric ultrasound scan. However, most medical centers now have ultrasound machines that improve fetal assessment. The umbilical cord should be routinely evaluated during a fetal assessment, and suspicion of an umbilical cord knot can be more frequently diagnosed and is detected only incidentally. Clinical outcome is usually good but depends on the knot's characteristics and if it is tight or loose. In this review, we discuss pathophysiology, the theories on formation, the main risk factors, ultrasound signs and findings, different opinions in the management, and features of pregnancy outcomes feature.

The Spectrum of clinical manifestations in newborns with the COQ4 mutation: case series and literature review.

Coenzyme Q10 (CoQ10) plays an important role in the electron transport chain within the human mitochondrial respiratory chain. The manifestations of this deficiency exhibit a diverse range. This study investigates the clinical manifestations of primary coenzyme Q10 deficiency in neonates with the COQ4 mutation to improve the diagnosis of the disease and the prognosis through targeted treatment. We report 4 patients with primary coenzyme Q10 deficiency by COQ4 variants in neonates. A comprehensive literature search and review for original articles and case reports with COQ4 mutation published from January 1989 to November 2023 was performed through Pubmed. We review clinical manifestations, diagnostic approaches, and treatment monitoring in these and 20 previously reported patients. Within the cohort of four cases examined, three females and one male were identified from two distinct families. Specifically, case 1 and 2 consisted of monoamniotic twins. Cases 3 and 4 were siblings. A comprehensive review of 20 cases involving neonatal-onset COQ4 mutation was conducted. Half of the cases are Chinese. There was no statistically significant difference in the mortality between Chinese (9/12, 75%) and other regions (11/12, 91.7%) (P = 0.27). The survival time for the 24 cases was 60.0 ± 98.0 days (95% confidence interval CI: 0-252.0 days). The incidence of prenatal abnormalities in preterm infants was significantly higher than that in full-term infants (66.7% vs. 16.7%, P = 0.02). Hyperlactatemia was one of the most common manifestations, accounting for 75% of cases (18/24). Twenty of the 24 cases were diagnosed by whole exome sequencing. Only 9 patients received exogenous coenzyme Q10 treatment, and all the 4 surviving patients received coenzyme Q10 supplementation. The prognosis of COQ4 mutation in the neonatal period indicates a low survival rate and an poor prognosis. This may be due to the incomplete understanding of the mechanism of how COQ4 gene defects lead to coenzyme Q10 deficiency and why CoQ10 supplementation does not respond well to treatment. To improve the diagnostic rate, in addition to genetic testing, mitochondrial functional verification should be prioritized in southern China, where the incidence is relatively high. It will facilitate more in-depth mechanistic studies.

Umbilical Cord Abnormality in a Monochorionic-Monoamniotic Twin Pregnancy.

Umbilical Cord Abnormality in a Monochorionic-Monoamniotic Twin Pregnancy.

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.

Maternal and neonatal outcomes of twin pregnancies complicated by gestational diabetes mellitus

IntroductionGestational diabetes mellitus (GDM) is associated with a higher risk of adverse maternal outcomes, but its effects on maternal and perinatal outcomes of twin pregnancies remain conflicting.MethodsThis retrospective cohort study included all primipara who delivered twin pregnancies at a single tertiary perinatal center between January 1, 2016 and December 31, 2022. Excluded were those who had a single pregnancy, twin pregnancies with pre-existing diabetes, missing information on GDM screening, a delivery before gestational 28 weeks, complications related to monochorionic placentation, multifetal reduction, fetal anomalies, and monochorionic monoamniotic twins. Maternal outcomes included preterm birth, pre-eclampsia, hypothyroidism, preterm premature rupture of membranes (PROM), placental abruption, severe postpartum hemorrhage, and oligohydramnios. Neonatal outcomes included small-for-gestational-age (SGA), large-for-gestational-age (LGA), birthweight, Apgar score, neonatal intensive care unit (NICU) admission, extrauterine growth restriction (EUGR), and neonatal hypoglycemia.ResultsA total of 3269 twins were delivered, with 897 women (27.4%) diagnosed with GDM during pregnancies; moreover, 72 (8.0%) of these women received insulin treatment. The GDM group showed a significantly higher maternal age at delivery (≥35 years), as well as incidences of overweight and obesity. These factors also elevated the odds of insulin treatment in GDM women with twin pregnancies (OR = 1.881, 95% CI = 1.073–3.295, P = 0.027; OR = 2.450, 95% CI = 1.422–4.223, P < 0.001; OR = 4.056, 95% CI = 1.728–9.522, P < 0.001, respectively). Chronic hypertension prior to pregnancy was identified as a risk factor for GDM during twin pregnancies (OR = 1.896, 95% CI = 1.290–2.785, P < 0.001), although it did not increase the proportion of women requiring insulin treatment (P = 0.808). Aside from a higher incidence of preterm birth before 37 weeks in insulin-treated GDM twins (OR = 2.096, 95% CI = 1.017–4.321, P = 0.045), there were no significant difference in other maternal outcomes (preterm birth before 34 weeks, pre-eclampsia, hypothyroidism, PROM, placental abruption, placenta previa, severe postpartum hemorrhage, and oligohydramnios) between the GDM group and non-GDM group, and between insulin-treated GDM and non-insulin-treated GDM. The rate of newborns with birthweight <1500 g was significantly lower among twins born to GDM women, but the prevalence of EUGR was notably higher. Additionally, the risk of EUGR was elevated in insulin-treated GDM twins (OR = 3.170, 95% CI = 1.639,6.131, P < 0.001). No significant differences were observed between the GDM group and non-GDM group, or between insulin-treated GDM and non-insulin-treated GDM group in terms of mean birthweight, newborn sex ratio, and incidences of other adverse neonatal outcomes, including gestational age at delivery, LGA, birth weight <2500 g, and 1-min and 5-min Apgar scores.ConclusionMaternal age ≥35 years, overweight or obesity, and chronic hypertension are significant risk factors for GDM during twin pregnancies. Women with GDM during twin pregnancies may achieve similar outcomes compared to those without GDM. However, the women with GDM during twin pregnancies receiving insulin therapy may have a higher risk of preterm birth and EUGR.

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.

Validation of Ultrasound Dating Protocols Using Data From Twins Conceived Through In Vitro Fertilization in Nova Scotia: A Retrospective Cohort Study

ObjectivesClinical practice guidelines recommend determining gestational age (GA) for twin pregnancies using the fetal crown rump length (CRL) of the larger fetus. This study investigated whether the CRL of the larger or smaller fetus at 11–14 weeks best predicted in vitro fertilization (IVF) assigned GA. MethodsA retrospective cohort study of twin pregnancies conceived by IVF ± intracytoplasmic sperm injection, 2004–2022, generated GA estimations for each co-twin CRL at the 11–14 week ultrasound, to determine which fetus (smaller or larger) more consistently predicted IVF-assigned GA. Monoamniotic twins and twins with known structural or vascular abnormalities were excluded. Paired t tests evaluated the ability of CRL to predict GA, and logistic regression evaluated the predictive ability of each of the co-twin groups with increasing size differences. Statistical significance was set at P < 0.05. ResultsViewpoint 6 identified 359 eligible twin pairs. CRL was closest with the smaller fetus (0.38 days); CRL for both the smaller (95% CI 0.16–0.61) and the larger (2.25 days, 95% CI 2.04–2.46) fetus showed deviation from IVF-assigned GA. As the absolute difference between the small and large fetus increased, the ultrasound-estimated GA of the smaller fetus was still consistently closer to IVF-assigned GA. ConclusionsIn this selected population of twins with known GA, the CRL of the smaller fetus more accurately predicted IVF-assigned GA even with increasing differences in fetal size. These findings provide important information for appropriately dating pregnancies to facilitate adherence to national guidelines to monitor for pregnancy complications, and plan frequency and type of fetal surveillance, as well as timing of delivery.

Diprosopus Tetrophthalmus Including Radiological and Post-Partum Images- A Case Report

Introduction: Conjoint twinning is very uncommon with an incidence of approximately 1:50,000 to 1:100,000. Diprosopus tetrophthalmus is the rarest variant of conjoined twinning which results from incomplete monozygotic, monochorionic and monoamniotic twin division associated with multiple congenital malformations. A 25 years old female patient at 26 weeks of gestation having single gravida (primi) and no significant family history was referred to our radiology department for anomalies scan. Transabdominal obstetric ultrasound showed the fetus with one head, two faces, two legs, two hands, one thorax, one abdomen and a single spinal cord with deformed spine. The aim of this case report was to present and discuss a case of Diprosopus tetrophthalmus (craniofacial duplication) a rare variant of conjoined twins resulted from incomplete monozygotic, monochorionic and monoamniotic twin division which help in prenatal counseling to the patient and its management.

Single fetal demise in monochorionic twins: How to predict cerebral injury in the survivor co-twin?

The aims of the study were to evaluate perinatal outcome in monochorionic (MC) twins complicated with single intrauterine fetal death, spontaneously vs after fetal therapy, and to assess antenatal events that increase the risk of cerebral injury. Historical cohort study of MC pregnancies with single intrauterine fetal death diagnosed or referred to a tertiary referral hospital (2012-2020). Adverse perinatal outcome included termination of pregnancy, perinatal death, abnormal fetal or neonatal neuroimaging and abnormal neurological development. A total of 68 MC pregnancies with single intrauterine fetal death after 14 weeks of gestation were included. Sixty-five (95.6%) occurred in complicated MC pregnancies (twin to twin transfusion syndrome: 35/68 [51.5%]; discordant malformation: 13/68 [19.1%], selective intrauterine growth restriction: 10/68 [14.7%], twin reversed arterial perfusion sequence: 5/68 [7.3%] and cord entanglement in monoamniotic twins: 2/68 [2.94%]). In 52 cases (76.5%) single intrauterine fetal demise occurred after fetal therapy and in 16 (23.5%) occurred spontaneously. Cerebral damage included 14/68 cases (20.6%): 6/68 cases (8.82%) were prenatal lesions and 8/68 cases (11.8%) were postnatal. Risk of cerebral damage tended to be higher in the spontaneous death group (6/16, 37.5%) compared to the therapy-group (8/52, 15.38%) (p = 0.07). The risk increased with gestational age at intrauterine death (OR 1.21, 95% CI: 1.04-1.41, p = 0.014) and was higher in those surviving co-twins who developed anemia (OR 9.27, 95% CI: 1.50-57.12, p = 0.016). Pregnancies complicated with selective intrauterine growth restriction tended to be at higher risk for neurological damage (OR 2.85, 95% CI: 0.68-11.85, p = 0.15). Preterm birth rate (<37 weeks of pregnancy) was 61.7% (37/60). Seven of eight postnatal cerebral lesions (87.5%) were related to extreme prematurity. Overall perinatal survival rate was 88.3% (57/68) and 7% (4/57) of children had an abnormal neurological outcome. Risk of cerebral damage in single intrauterine fetal death is especially high when it occurs spontaneously. Gestational age at single intrauterine fetal death, selective intrauterine growth restriction and anemia of the surviving co-twin are the main predictors for prenatal lesions and might be useful in parent counseling. Abnormal postnatal neurological outcome is closely related to extreme prematurity.

Comparison of international guidelines on the management of twin pregnancy

ObjectivesTo review current international clinical guidelines on the antenatal and intrapartum management of twin pregnancies, examining areas of consensus and conflict. MethodsWe conducted a database search using Medline, Pubmed, Scopus, Academic Search Complete, CINAHL and ERCI Guidelines website. Guidelines were screened for eligibility using our inclusion and exclusion criteria. Those deemed eligible were quality assessed using the AGREE II tool and relevant data was extracted. ResultsWe identified 21 relevant guidelines from 16 countries including two international society guidelines. There was consensus in determination of chorionicity and amnionicity within the first trimester, fetal anomaly scan between 18 and 22 weeks and the recommended screening for twin-to-twin transfusion syndrome (TTTS).For those that provided intrapartum guidance, there was agreement in recommending caesarean section to deliver monochorionic monoamniotic (MCMA) twins, epidural anaesthesia for intrapartum analgesia and the use of cardiotocography (CTG) for intrapartum fetal monitoring.The main areas of conflict included cervical length screening, frequency of ultrasound surveillance, timing of delivery of dichorionic twin pregnancies and circumstances for recommending vaginal delivery. There was a lack of advice on intrapartum management. ConclusionsThis review has highlighted the need for unified international guidance on the management of twin pregnancy. Comparisons of current guidance demonstrates a lack of confidence in the management of labour in twin pregnancies. Further evidence on intrapartum care of twin pregnancies is needed to inform practice guidelines and improve both short and long term maternal and fetal outcomes.

Comparative Study of Perinatal Outcome in Uncomplicated Monochorionic Diamniotic versus Dichorionic Diamniotic Twins at a Specialized Twin Clinic—A Prospective Study

Abstract Background Monochorionic twins have higher perinatal morbidity and mortality than dichorionic twins. However, there is conflicting data on outcomes of uncomplicated monochorionic twins. Purpose of the Study The aim of this study is to compare the outcomes of apparently uncomplicated monochorionic twins to dichorionic twins. Methods This is a prospective study conducted from August 2019 to December 2020 at a specialized twin clinic. All twins, whose chorionicity was determined before 14 weeks with two live fetuses at 24 weeks, were recruited. Complicated monochorionic diamniotic (MCDA) twins with twin-to-twin transfusion syndrome, twin anemia polycythemia syndrome, selective fetal growth restriction before 24 weeks and single or double fetal demise before 24 weeks were excluded. Other exclusion criteria were major congenital and chromosomal abnormalities, higher order multiples, monoamniotic twins, and twins with undetermined chorionicity antenatally. Both the groups were followed till delivery and neonates followed till 28 days. Maternal and neonatal outcomes were studied and compared. Results One-hundred forty-eight mothers with dichorionic diamniotic (DCDA) and 74 with uncomplicated MCDA were studied. Mean gestational age at delivery was 35 weeks in both the groups. Maternal, fetal, and neonatal morbidities were similar in both, except early onset preeclampsia that was higher in the DCDA group. Prospective risk of stillbirth for DCDA and MCDA after 24 weeks was 1.35 and 4.05%, respectively. Prospective risk of stillbirth for DCDA and MCDA after 30 weeks was 1.49 and 0%, respectively. Conclusion The maternal and perinatal outcomes in uncomplicated MCDA twins are similar to DCDA twins. Prospective risk of stillbirth after 30 weeks is extremely low. Hence, uncomplicated MCDA twins should not be delivered electively before 36 weeks.

Premature monochorionic monoamniotic twins have lower lung compliance at birth than matched dichorionic diamniotic twins.

Premature infants are born with immature lungs that demonstrate abnormal pulmonary function with differences in passive respiratory system compliance and resistance, and functional residual capacity. To our knowledge, no studies have evaluated differences in neonatal pulmonary function based on the type of twin gestation, or chorionicity. Given the effect of chorionicity on outcomes, we aimed to study the effect of twin type, monochorionic monoamniotic (MCMA) vs dichorionic diamniotic (DCDA), on neonatal early pulmonary function tests. In this prospective cohort study, 5 sets of DCDA twins were matched to 5 sets of MCMA twins on gestational age at delivery, latency from antenatal corticosteroid exposure, birthweight, race and gender. Mean values were compared for passive respiratory system compliance and resistance, functional residual capacity, and tidal volume. MCMA infants had a significantly lower compliance (0.64 vs 1.25 mL/cm H2O /kg; p = 0.0001) and significantly higher resistance (0.130 vs 0.087 cm H2O /mL/sec; p = 0.0003) than DCDA infants. Functional residual capacity was lower for MCMA than DCDA infants (17.5 vs 23.4 mL/kg; p = 0.17). Further, 80% of MCMA infants required intubation for surfactant administration compared to 20% of DCDA infants, indicating the clinical significance of these objective measures. Due to the matched case-control design, causality cannot be established. However, we speculate that these differences in lung function may derive from differential exposure to preterm labor and endogenous maternal corticosteroid exposure. Further study is necessary to establish the true causal relationship.