Reduced lung function during childhood in identical twins with discordant fetal growth: a cohort study.

Background: Fetal growth restriction (FGR) can negatively affect lung development, leading to increased respiratory morbidity and reduced lung function later in life. Studies regarding the impact of FGR on lung function in singletons are influenced by genetic, obstetric, and maternal factors. To overcome these confounding factors, we aim to investigate lung function in identical twins with selective FGR (sFGR). Methods: Lung function assessments were performed in identical twins with sFGR born in our centre between March 1, 2002, and December 31, 2017, aged between 5 and 17 years. sFGR was defined as birthweight discordance ≥20%. Outcome measures consisted of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and transfer factor for carbon monoxide (DLCO) and were compared between the smaller and larger twin. Findings: Thirty-nine twin pairs performed spirometry of sufficient quality. Median gestational age at birth was 34.3 (interquartile range (IQR) 32.1-36.0) weeks with median birthweights of 1500 (IQR 1160-1880) grams and 2178 (IQR 1675-2720) grams for the smaller and larger twin, respectively. Smaller twins had significantly lower z-scores for FEV1 (-0.94 versus -0.41, p = 0.0015), FVC (-0.56 versus -0.06, p < 0.0001) and DLCO (-0.50 versus 0.00, p < 0.0001) compared to larger co-twins. Interpretation: Although being genetically identical, sFGR in identical twins is associated with a reduction in static and dynamic lung volume and a reduction in lung diffusion, even when taking the reduced lung volume into account. This indicates that adverse growth conditions in utero negatively affect lung development and function, potentially contributing to an increase in respiratory morbidities later in life. Funding: The Dutch Heart Foundation and The Bontius Foundation.

The Current Knowledge of Cerebral Magnetic Resonance Imaging in Monochorionic Twins: A Systematic Review of the Last 20 Years.

The distinct placental angioarchitecture in monochorionic (MC) pregnancies increases the risk of complications such as twin-twin transfusion syndrome (TTTS), twin anemia polycythemia sequence (TAPS), and selective fetal growth restriction (sFGR). The aim of this systematic review was to evaluate the incidence, type, and severity of cerebral injury and structural brain development on fetal and/or neonatal cerebral magnetic resonance imaging (MRI) in MC twins with or without complications. Twenty-three studies were included, covering a wide range of complications observed during MC pregnancies, with studies involving sIUFD (n = 12), TTTS (n = 7), mixed complications (n = 2), TAPS (n = 1), and uncomplicated MC pregnancy (n = 1). TAPS and sFGR were largely underrepresented in the current literature. The included studies reported that MC pregnancies with single intrauterine fetal demise (sIUFD) are most at risk for cerebral injury during the fetal period. The overall median incidence of cerebral injury after sIUFD was 28.3% (0-55%). Severe antenatal cerebral injury after sIUFD was detected antenatally in 6.5% (0-36%) of the cases. Three of the included studies described the incidence, type, and severity of cerebral injury on neonatal MRI in MC twins. Structural brain development based on cerebral biometry was only assessed in two studies, revealing significantly smaller biometric measurements of the cerebrum in cases of single sIUFD or smaller twins compared to singleton pregnancies. To enhance our understanding of the potential risks and pathophysiological mechanisms associated with cerebral injury and structural brain development in MC twins, there is a need for future studies and standardized protocols using serial fetal and neonatal MRI imaging in addition to routine ultrasound imaging.

Fetal growth restriction inhibits childhood growth despite catch-up in discordant identical twins: an observational cohort study.

OBJECTIVE: Research suggests that postnatal catch-up growth after fetal growth restriction (FGR) occurs frequently. Yet, postnatal growth in singletons may be influenced by multiple factors. Identical twins with discordant prenatal growth, termed selective FGR (sFGR), can be regarded as a natural experiment eliminating these sources of bias. DESIGN: Observational cohort study. METHODS: Monochorionic twins with sFGR born between 2002 and 2017 (aged 3-17 years) were eligible. Growth measurements (height, weight, head circumference, and body mass index) were performed at follow-up. Detailed growth curves documented by a systematic primary care system in the Netherlands were collected. Measurements were converted to standard deviation scores (SDSs). A mixed-effects model was used to assess within-pair SDS difference and individual height SDS relative to target height SDS. RESULTS: Forty-seven twin pairs (94 children) were included at a median age of 11 (interquartile range 8-13) years. At the last measurement, smaller twins at birth had a lower height SDS [-0.6 vs -0.3, P < .001, median difference 0.5 (95%CI 0.4-0.7)], lower weight SDS [-0.5 vs -0.1, P < .001, median difference 0.8 (95%CI 0.5-1.0)], and lower head circumference SDS [-0.5 vs 0.2, P < .001, median difference 0.8 (95%CI 0.6-0.9)] compared to larger twins. These differences persisted until the age of 17. Smaller twins showed rapid catch-up growth in the first 2 years and reached their target height range between 8 and 11 years. CONCLUSIONS: Identical twins with discordant prenatal growth maintain a modest but significant difference in height, weight, and head circumference, indicating a persistent, inhibitory effect of an adverse intrauterine environment on childhood growth.

A robust and standardized method to isolate and expand mesenchymal stromal cells from human umbilical cord.

BACKGROUND AIMS: Human umbilical cord-derived mesenchymal stromal cells (hUC-MSCs) are increasingly used in research and therapy. To obtain hUC-MSCs, a diversity of isolation and expansion methods are applied. Here, we report on a robust and standardized method for hUC-MSC isolation and expansion. METHODS: Using 90 hUC donors, we compared and optimized critical variables during each phase of the multi-step procedure involving UC collection, processing, MSC isolation, expansion and characterization. Furthermore, we assessed the effect of donor-to-donor variability regarding UC morphology and donor attributes on hUC-MSC characteristics. RESULTS: We demonstrated robustness of our method across 90 UC donors at each step of the procedure. With our method, UCs can be collected up to 6 h after birth, and UC-processing can be initiated up to 48 h after collection without impacting on hUC-MSC characteristics. The removal of blood vessels before explant cultures improved hUC-MSC purity. Expansion in Minimum essential medium α supplemented with human platelet lysate increased reproducibility of the expansion rate and MSC characteristics as compared with Dulbecco's Modified Eagle's Medium supplemented with fetal bovine serum. The isolated hUC-MSCs showed a purity of ∼98.9%, a viability of >97% and a high proliferative capacity. Trilineage differentiation capacity of hUC-MSCs was reduced as compared with bone marrow-derived MSCs. Functional assays indicated that the hUC-MSCs were able to inhibit T-cell proliferation demonstrating their immune-modulatory capacity. CONCLUSIONS: We present a robust and standardized method to isolate and expand hUC-MSCs, minimizing technical variability and thereby lay a foundation to advance reliability and comparability of results obtained from different donors and different studies.

Intertwin Membrane Perforation and Umbilical Cord Entanglement after Laser Surgery for Twin-Twin Transfusion Syndrome: Prevalence, Risk Factors, and Outcome.

INTRODUCTION: Perforation of the intertwin membrane can occur as a complication of fetoscopic laser surgery for twin-twin transfusion syndrome (TTTS). Data on the occurrence and the risk of subsequent cord entanglement are limited. The objective of this study was to assess the prevalence, risk factors and outcome of intertwin membrane perforation, and cord entanglement after laser surgery for TTTS. METHODS: In this multicenter retrospective study, we included all TTTS pregnancies treated with laser surgery in two fetal therapy centers, Shanghai (China) and Leiden (the Netherlands) between 2002 and 2020. We evaluated the occurrence of intertwin membrane perforation and cord entanglement after laser, based on routine fortnightly ultrasound examination and investigated the risk factors and the association with adverse short- and long-term outcomes. RESULTS: Perforation of the intertwin membrane occurred in 118 (16%) of the 761 TTTS pregnancies treated with laser surgery and was followed by cord entanglement in 21% (25/118). Perforation of the intertwin membrane was associated with higher laser power settings, 45.8 Watt versus 42.2 Watt (p = 0.029) and a second fetal surgery procedure 17% versus 6% (p < 0.001). The group with intertwin membrane perforation had a higher rate of caesarean section (77% vs. 31%, p < 0.001) and a lower gestational age at birth (30.7 vs. 33.3 weeks of gestation, p < 0.001) compared to the group with an intact intertwin membrane. Severe cerebral injury occurred more often in the group with intertwin membrane perforation, 9% (17/185) versus 5% (42/930), respectively (p = 0.019). Neurodevelopmental outcome at 2 years of age was similar between the groups with and without perforation of the intertwin membrane and between the subgroups with and without cord entanglement. CONCLUSION: Perforation of the intertwin membrane after laser occurred in 16% of TTTS cases treated with laser and led to cord entanglement in at least 1 in 5 cases. Intertwin membrane perforation was associated with a lower gestational age at birth and a higher rate of severe cerebral injury in surviving neonates.

Association between fetal growth-restriction and retinopathy of prematurity using a unique identical twin model.

BACKGROUND: Research in singletons identified fetal growth restriction (FGR) as a risk factor for retinopathy of prematurity (ROP), but is generally subject to confounding by genetic, obstetric, and maternal factors. We investigated the effect of FGR on ROP in growth-discordant identical twins, thereby controlling for confounding factors. METHODS: All data of monochorionic (MC) twin pairs with a birth weight discordance ≥20% born in our center between 2010 and 2021 were retrospectively reviewed for the presence of ROP. Potential risk factors for ROP were analyzed. Outcomes were compared between the smaller and larger twin. RESULTS: We included 88 MC twin pairs with growth discordance. In 34% (30/88), both neonates were at risk of ROP. Prevalence of ROP was higher among the smaller twin compared to the larger twin, 30% (9/30) versus 13% (4/30), respectively (OR 2.8, 95% CI: 1.2-6.6). The smaller twin had a longer duration of mechanical ventilation (8 (1-20) versus 2 (1-4) days) and received their first red blood cell transfusion at an earlier postmenstrual age (29.6 (28.1-31.6) versus 30.4 (29.7-32.6) weeks). CONCLUSIONS: In this identical twin model, FGR is associated with almost tripled odds of ROP development, suggesting that both unfavorable antenatal growth conditions and adverse neonatal outcomes affect postnatal retinal vascular proliferation. IMPACT: Fetal growth restriction in growth-discordant identical twins is associated with almost tripled odds of developing retinopathy of prematurity in the smaller twin. Since these twins do not only differ in birth weight but also duration of mechanical ventilation and timing of the first red blood cell transfusion, both unfavorable antenatal growth conditions and adverse neonatal outcomes can affect postnatal retinal vascular proliferation. More attention for preventing retinopathy of prematurity is needed in those with fetal growth restriction who received prolonged duration of mechanical ventilation, oxygen supplementation, or a first red blood cell transfusion <32 weeks postmenstrual age.

Children Newly Diagnosed with Fetal and Neonatal Alloimmune Thrombocytopenia: Neurodevelopmental Outcome at School Age.

OBJECTIVE: To evaluate the neurodevelopmental outcome at school age in children newly diagnosed with fetal and neonatal alloimmune thrombocytopenia (FNAIT). STUDY DESIGN: This observational cohort study included children diagnosed with FNAIT between 2002 and 2014. Children were invited for cognitive and neurological testing. Behavioral questionnaires and school performance results were obtained. A composite outcome of neurodevelopmental impairment (NDI) was used, defined, and subdivided into mild-to-moderate and severe NDI. Primary outcome was severe NDI, defined as IQ <70, cerebral palsy with Gross Motor Functioning Classification System level ≥ III, or severe visual/hearing impairment. Mild-to-moderate NDI was defined as IQ 70-85, minor neurological dysfunction or cerebral palsy with Gross Motor Functioning Classification System level ≤ II, or mild visual/hearing impairment. RESULTS: In total, 44 children were included at a median age of 12 years (range: 6-17 years). Neuroimaging at diagnosis was available in 82% (36/44) of children. High-grade intracranial hemorrhage (ICH) was detected in 14% (5/36). Severe NDI was detected in 7% (3/44); two children had high-grade ICH, and one had low-grade ICH and perinatal asphyxia. Mild-to-moderate NDI was detected in 25% (11/44); one child had high-grade ICH, and eight children were without ICH, yet for two children, neuroimaging was not performed. Adverse outcome (perinatal death or NDI) was 39% (19/49). Four children (9%) attended special needs education, three of whom had severe NDI and one had mild-to-moderate NDI. Total behavioral problems within the clinical range were reported in 12%, which is comparable with 10% in the general Dutch population. CONCLUSION: Children who are newly diagnosed with FNAIT are at increased risk for long-term neurodevelopmental problems, even those without ICH. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (Identifier: NCT04529382).

Automated oxygen control for very preterm infants and neurodevelopmental outcome at 2 years-a retrospective cohort study.

Faster resolution of hypoxaemic or hyperoxaemic events in preterm infants may reduce long-term neurodevelopmental impairment. Automatic titration of inspiratory oxygen increases time within the oxygen saturation target range and may provide a more prompt response to hypoxic and hyperoxic events. We assessed routinely performed follow-up at 2 years of age after the implementation of automated oxygen control (AOC) as standard care and compared this with a historical cohort. Neurodevelopmental outcomes at 2 years of age were compared for infants born at 24-29 weeks gestational age before (2012-2015) and after (2015-2018) the implementation of AOC as standard of care. The primary outcome was a composite outcome of either mortality or severe neurodevelopmental impairment (NDI), and other outcomes assessed were mild-moderate NDI, Bayley-III composite scores, cerebral palsy GMFCS, and CBCL problem behaviour scores. A total of 289 infants were included in the pre-AOC epoch and 292 in the post-AOC epoch. Baseline characteristics were not significantly different. Fifty-one infants were lost to follow-up (pre-AOC 6.9% (20/289), post-implementation 10.6% (31/292). The composite outcome of mortality or severe NDI was observed in 17.9% pre-AOC (41/229) vs. 24.0% (47/196) post-AOC (p = 0.12). No significant differences were found for the secondary outcomes such as mild-moderate NDI, Bayley-III composite scores, cerebral palsy GMFCS, and problem behaviour scores, with the exception of parent-reported readmissions until the moment of follow-up which was less frequent post-AOC than pre-AOC. CONCLUSION: In this cohort study, the implementation of automated oxygen control in our NICU as standard of care for preterm infants led to no statistically significant difference in neurodevelopmental outcome at 2 years of age. WHAT IS KNOWN: • Neurodevelopmental outcome is linked to hypoxemia, hyperoxaemia and choice of SpO2 target range. • Automated titration of inspired oxygen may provide a faster resolution of hypoxaemic and hyperoxaemic events. WHAT IS NEW: • This cohort study did not find a significant difference in neurodevelopmental outcome at two years of age after implementing automated oxygen control as standard of care.

Insecure attachment and internalizing behavior problems in growth discordant identical twins.

BACKGROUND: Psychosocial development in monochorionic (MC) twins born after selective fetal growth restriction (sFGR) has been unreported to date, despite its importance for daily functioning and future relationships. AIMS: To investigate psychosocial development, attachment and school functioning in MC twins with sFGR and compare outcomes with the general population and between smaller and larger twins. STUDY DESIGN: Observational cohort study. SUBJECTS: MC twins with sFGR (defined as a birth weight discordance ≥20 %) born between 2002 and 2017 and aged 3-17 years. OUTCOME MEASURES: Multiple parent report questionnaires: the Child Behavior Checklist (social-emotional development and behavior), the (Early) Childhood Behavior Questionnaire Very Short Form (temperament), the Attachment Insecurity Screening Inventory (attachment) and a school functioning questionnaire. RESULTS: Median age for the 48 twin pairs was 11 (interquartile range (IQR) 8-13) years. Attachment insecurity for both twins was higher than in the general population for ambivalence/resistance (34 % (21/62) vs. 16 %, p = 0.024) and total attachment insecurity (35 % (22/62) vs. 16 %, p = 0.016). Smaller twins had more internalizing behavioral problems, i.e. negative emotions and behaviors turned inwards (22 % (10/46) vs. 11 % (5/46), p = 0.021) and a higher negative affect, i.e. more likely to experience negative emotions (3.2 (2.9-3.7) vs. 2.9 (2.2-3.2), p = 0.009) than larger twins, as well as a lower secondary school level (p = 0.031). CONCLUSION: MC twins with sFGR have more ambivalent/resistant attachment insecurity following the complicated pregnancy course. Smaller twins have a tendency towards negative emotions and internalizing behaviors compared to larger twins, indicating an increased sensitivity for depression and anxiety.

Gestational age at birth and outcome in monochorionic twins with different types of selective fetal growth restriction: A systematic literature 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.

Long-term effects of selective fetal growth restriction (LEMON): a cohort study of neurodevelopmental outcome in growth discordant identical twins in the Netherlands.

BACKGROUND: Singletons born after fetal growth restriction (FGR) are at increased risk of poor neurodevelopmental outcomes. Studies of singletons with FGR usually compare outcomes with those without FGR, a comparison that is inherently biased by obstetrical, parental, and genetic factors. We aim to compare neurodevelopmental outcomes between the smaller and larger twin in a population of discordant identical twins who shared a single placenta (monochorionic diamniotic), naturally eliminating these confounders. METHODS: This study is part of the cohort study LEMON of monochorionic diamniotic twins with selective FGR. All monochorionic diamniotic twins with selective FGR who were born in Leiden University Medical Center (Leiden, Netherlands) between March 1, 2002, and Dec 31, 2017, were eligible for inclusion. Twin pregnancies that were complicated by twin-twin transfusion syndrome, twin anaemia polycythaemia sequence, or monoamnionicity were excluded. Cognitive performance was evaluated with two standardised psychometric age-appropriate tests, producing a full-scale intelligence quotient (FSIQ). Motor functioning was assessed with a standardised neurological examination. A composite outcome of neurodevelopmental impairment (NDI) was used, subdivided into mild NDI (defined as FSIQ <85, minor neurological dysfunction or cerebral palsy grade 1, or mild visual or hearing impairment) and severe NDI (defined as FSIQ <70, severe neurological dysfunction, or severe visual or hearing impairment). FINDINGS: Between Jan 25, 2021, and March 15, 2022, 47 twin pairs were enrolled in the study and underwent neurodevelopmental assessment. The median gestational age at birth was 33·9 weeks (IQR 31·3-36·0) for the 47 included twin pairs, with median birthweights of 1400 g (1111-1875) in the smaller twin and 2003 g (1600-2680) in the larger twin. The median age at neurodevelopmental assessment was 11 years (8-13). Median FSIQ was 94 (86-101) for the smaller twin and 100 (92-108) for the larger twin (p<0·0001). More smaller twins had mild NDI (17 [36%] of 47) than did the larger twins (five [11%] of 47; odds ratio 4·8 [95% CI 1·6-14·1]; p=0·0049). There was no difference in the proportion of children with severe NDI (two [4%] of 47 in both groups, p=1·0). INTERPRETATION: As mild NDI can impede children in their daily functioning, we recommend standardised long-term follow-up, including neurodevelopmental testing, for monochorionic diamniotic twins with selective FGR to facilitate early identification of children at risk. FUNDING: The Dutch Heart Foundation.

Impact of placental sharing and large bidirectional anastomoses on birthweight discordance in monochorionic twins: a retrospective cohort study in 449 cases.

BACKGROUND: In monochorionic twin pregnancies, the fetuses share a single placenta. When this placenta is unequally shared, a discordant antenatal growth pattern ensues resulting in high rates of perinatal morbidity and mortality. Understanding placental pathophysiology is paramount in devising feasible antenatal management strategies. Unequal placental sharing is not the sole determinant of birthweight discordance as there is no one-to-one relationship with placental share discordance. Placental angioarchitecture, especially the presence of large bidirectional anastomoses, is thought to affect this relationship by allowing for a compensatory intertwin blood flow. OBJECTIVE: This study aimed to assess whether placental angioarchitecture can affect birthweight discordance in live-born monochorionic twins, the aim of our study was 2-fold: (1) to assess the relationship between birthweight discordance and placental share discordance and (2) to examine to what extent large bidirectional anastomoses can compensate for the effect of unequal placental sharing on birthweight discordance, with a subgroup analysis for umbilical artery Doppler flow patterns in cases with a birthweight discordance of ≥20%. STUDY DESIGN: This was a retrospective cohort study that included monochorionic twin pregnancies observed in our center between March 2002 and June 2021, in which twins with a birthweight discordance of ≥20% were classified according to umbilical artery Doppler flow patterns of the smaller twin. We excluded cases with twin-twin transfusion syndrome and twin anemia polycythemia sequence. Monochorionic placentas of live-born twins were injected with dye, and images were saved for computer measurements of placental sharing and the diameter of anastomoses. Univariate linear regressions of the relationship between placental share discordance and birthweight discordance (both calculated as larger weight or share-smaller weight or share/larger weight or share×100%) and the relationship between arterioarterial and venovenous diameters and birthweight ratio/placental territory ratio were performed. RESULTS: A total of 449 placentas were included in the analysis. Placental share discordance was positively correlated with birthweight discordance (ß coefficient, 0.325; 95% confidence interval, 0.254-0.397; P<.0001). The arterioarterial diameter was negatively correlated with birthweight ratio/placental territory ratio (ß coefficient, -0.041; 95% confidence interval, -0.059 to -0.023; P<.0001), meaning that an increase in arterioarterial diameter leads to less birthweight discordance than expected for the amount of placental share discordance. There was no relationship between venovenous diameter and birthweight ratio/placental territory ratio (ß coefficient, -0.007; 95% confidence interval, -0.027 to 0.012; P=.473). CONCLUSION: Birthweight discordance in monochorionic twins was strongly associated with placental share discordance. Large arterioarterial anastomoses can mitigate the effect of unequal placental sharing.

Long-term neurodevelopmental outcome in children after antenatal intravenous immune globulin treatment in fetal and neonatal alloimmune thrombocytopenia.

BACKGROUND: Children with fetal and neonatal alloimmune thrombocytopenia face increased risk of intracranial hemorrhage potentially leading to developmental impairment. To prevent intracranial hemorrhage, pregnant women with alloantibodies against fetal platelets are often treated with intravenous immunoglobulin. Intravenous immunoglobulin seems effective in vastly reducing the risk of fetal or neonatal bleeding complications. However, information on long-term neurodevelopment of these children is lacking. OBJECTIVE: This study aimed to evaluate long-term neurodevelopmental outcome in children with fetal and neonatal alloimmune thrombocytopenia who were treated with intravenous immunoglobulin antenatally. STUDY DESIGN: An observational cohort study was performed, including children of mothers treated with intravenous immunoglobulin during pregnancy because a previous child was diagnosed with fetal and neonatal alloimmune thrombocytopenia. Children were invited for a follow-up assessment including standardized cognitive and neurologic tests. The parents were asked to complete a behavioral questionnaire and school performance reports. The primary outcome was severe neurodevelopmental impairment, defined as severe cognitive impairment (intelligence quotient <70), cerebral palsy with Gross Motor Function Classification System Level ≥3, bilateral blindness, and/or bilateral deafness (requiring amplification). The secondary outcome was mild to moderate neurodevelopmental impairment, defined as either mild to moderate cognitive impairment (intelligence quotient <85), cerebral palsy with Gross Motor Function Classification System Level ≤2, minor neurologic dysfunction, vision loss, and/or hearing loss. RESULTS: Between 2003 and 2017, 51 children were live-born after antenatal intravenous immunoglobulin treatment. One family moved abroad and was therefore not eligible for inclusion. In total, 82% (41/50) of the eligible cases were included for neurodevelopmental assessment at a median age of 9 years and 8 months. Severe neurodevelopmental impairment was not detected. The incidence of mild to moderate neurodevelopmental impairment was 14% (6/41; 95% confidence interval, 6%-29%). The children's mean cognitive score, behavioral scores, and academic achievement were not different from those observed in the Dutch norm groups. Neuroimaging was performed in 90% (37/41) of cases. Severe intracranial hemorrhage was diagnosed in 2 cases (5%), one antenatally before the start of intravenous immunoglobulin and the other case 1 day after birth. Both cases had a normal neurodevelopmental outcome. CONCLUSION: The risk of neurodevelopmental impairment in children whose mothers were treated for fetal and neonatal alloimmune thrombocytopenia with antenatal intravenous immunoglobulin is comparable to that reported in the general population.

Long-term follow-up of complicated monochorionic twin pregnancies: Focus on neurodevelopment.

Monochorionic twin pregnancies have an increased risk of morbidity and mortality. Due to the advancements in screening and treatment strategies, mortality rates have decreased. Improving survival rates demands a shift in scope toward long-term outcomes. In this review, we focus on neurodevelopmental outcome in survivors from complicated monochorionic twin pregnancies, including twin-twin transfusion syndrome (TTTS), twin anemia-polycythemia sequence (TAPS), acute peripartum TTTS, acute perimortem TTTS, selective fetal growth restriction (sFGR) and monoamnionicity. Our aim is to provide an overview of the current knowledge on the long-term outcome in survivors, including psychomotor development and quality of life, and provide recommendations for future research and follow-up programs.

Neurodevelopmental Trajectories of Preterm Born Survivors of Twin-Twin Transfusion Syndrome: From Birth to 5 Years of Age.

OBJECTIVE: To investigate the neurodevelopmental outcome at age 2 and 5 years in survivors of twin-twin transfusion syndrome (TTTS) treated with fetoscopic laser surgery and born premature and/or small for gestational age. STUDY DESIGN: At 2 and 5 years of age, standardized neurologic, motor, and cognitive assessments were performed by a neonatologist, a pediatric physical therapist, and a psychologist. Behavior was assessed using a validated questionnaire completed by parents. RESULTS: Neurodevelopmental assessment at both time points was available for 73 survivors of TTTS. Mild to moderate neurodevelopmental impairment (NDI) was detected in 34% of survivors (25 of 73) at 5 years, compared with 25% (18 of 73) at 2 years (P = .178). Severe NDI was observed in 12% (9 of 73) at 5 years and in 3% (2 of 73) at 2 years (P = .035). Mean cognitive score was lower at the 5-year follow-up (90.7 ± 12.3 vs 95.6 ± 13.1 at 2 years; P = .001), and more children were diagnosed with mild cognitive impairment at 5 years (29% vs 11% at 2 years; P = .007). When comparing individual outcomes at both time points, 35% (25 of 71) moved from a normal outcome or mild to moderate impairment at 2 years toward more severe impairment at 5 years. CONCLUSIONS: A high rate of mild to moderate cognitive impairment and severe NDI at age 5 years was not identified at age 2 years. Our data highlight the importance of longitudinal follow-up of survivors of TTTS beyond age 2 years and emphasize the precautions that should be taken when diagnosing an absence of impairment before school age.

Placental Abruption after Fetoscopic Laser Surgery in Twin-Twin Transfusion Syndrome: The Role of the Solomon Technique.

INTRODUCTION: Twin-twin transfusion syndrome (TTTS) is a complication in monochorionic twin pregnancies which is preferably treated with fetoscopic laser surgery. A few small studies suggested a possible association between the Solomon laser technique and placental abruption. METHODS: The objective of this study is to compare the rate of and to explore potential risk factors for placental abruption in TTTS treated with fetoscopic laser surgery according to the Selective and Solomon laser technique. We conducted a large retrospective cohort study of consecutive TTTS-cases treated with fetoscopic laser surgery in Shanghai, China, and Leiden, The Netherlands treated with either the Selective laser technique (Selective group) or Solomon laser technique (Solomon group). RESULTS: The rate of placental abruption in the Selective group versus the Solomon group was 1.7% (5/289) and 3.4% (15/441), respectively (p = 0.184). No risk factors for placental abruption were identified. Placental abruption was associated with lower gestational age at birth (p = 0.003) and severe cerebral injury (p = 0.003). CONCLUSION: The prevalence of placental abruption in TTTS after fetoscopic laser surgery is low, although it appears higher than in the overall population. Placental abruption is associated with a lower gestational age at birth, which is associated with severe cerebral injury. The rate of placental abruption was not significantly increased with the use of the Solomon technique. Continued research of placental abruption in TTTS is necessary to determine why the rate is higher than in the overall population.

Longitudinal Follow-Up of Children Born Preterm: Neurodevelopment From 2 to 10 Years of Age.

Objective: To investigate the rate and stability of impairments in children born preterm by assessing (1) early and school-age outcome in four developmental domains and (2) individual changes in outcome at both timepoints. Design: Prospective, longitudinal cohort study in children born in 2006-2007, <32 weeks' gestation. Follow-up at 2 and 10 years of age included standardized neurological, motor, cognitive and behavioral assessments. Children were categorized as having no, mild or moderate-severe impairment in these four domains. A composite impairment score was composed and the number of domains with impairments counted. For each child, individual outcomes at both timepoints were compared. Results: Follow-up at both time-points was available in 71/113(63%) children. At group level, there were no significant changes in the severity of impairments per domain. However, at individual level, there were less children with a mild abnormal composite score at 10 years of age (44 vs. 20%; p = 0.006), and more with a moderate-severe abnormal composite score (12 vs. 35%; p = 0.001). Especially children with normal/mild outcome at 2 years were likely to shift to other outcome categories over time. Conclusions: Children with early severe impairment are likely experiencing impairments later on, but early normal/mild abnormal outcomes should be interpreted with care, considering the large individual shifts over time. Long-term follow-up in all children born very preterm should therefore be continued to at least school-age.

Respiratory distress syndrome and bronchopulmonary dysplasia after fetal growth restriction: Lessons from a natural experiment in identical twins.

BACKGROUND: Fetal growth restriction (FGR) is thought to negatively affect lung development resulting in increased respiratory morbidity. However, research performed in singletons is often limited by a certain level of bias caused by individual differences in genetic constitution, obstetrical and maternal factors. METHODS: Respiratory morbidity was compared between the smaller and the larger twin in monochorionic twins with selective fetal growth restriction (sFGR), defined as a birth weight discordance ≥ 20%, born in our center between 2010 and 2019 in this retrospective study. Respiratory distress syndrome (RDS) was diagnosed based on the clinical picture of a neonate with respiratory failure requiring mechanical ventilation and/or surfactant, confirmed by a chest X-ray. Bronchopulmonary dysplasia (BPD) was diagnosed when the neonate required treatment with >21% oxygen for at least 28 days. FINDINGS: Median gestational age at birth for the 94 included pregnancies was 32.4 (IQR 30.4-34.3) weeks. Within-pair analyses showed that the prevalence of RDS was lower in the smaller twin compared to the larger twin, 19.1% (18/94) vs 34.0% (32/94), respectively (p = 0.004). The odds of RDS for the larger twin was doubled (OR 2.1 (CI95% 1.3-3.5). In contrast, the rate of BPD in the smaller twin was higher as opposed to the larger twin, 16.7% (15/90) vs 6.7% (6/89), respectively (p = 0.008), with a more than doubled odds (OR 2.5 (CI95% 1.3-4.9)). INTERPRETATION: Despite being genetically identical, sFGR twins have different respiratory outcomes. Adverse growth condition in utero in the smaller twin is associated with a reduced odds of RDS at birth but a more than doubled odds of BPD, reflecting the pathophysiologic adverse effect of growth restriction on lung development. FUNDING: The Dutch Heart Foundation (2017T075).

Prevalence, risk factors, and outcome of postprocedural amniotic band disruption sequence after fetoscopic laser surgery in twin-twin transfusion syndrome: a large single-center case series.

BACKGROUND: Postprocedural amniotic band disruption sequence is a condition that is associated with intrauterine interventions, and it is characterized by a constriction of the limbs or umbilical cord by fibrous strands, leading to edema, amputation, and/or fetal demise. OBJECTIVE: To evaluate the prevalence of, risk factors for, and the outcome of postprocedural amniotic band disruption sequence after fetoscopic laser surgery in twin-twin transfusion syndrome cases. STUDY DESIGN: All consecutive cases of twin-twin transfusion syndrome treated with fetoscopic laser coagulation of the vascular anastomoses at our center between January 2002 and March 2019 were included in the study. The occurrence of postprocedural amniotic band disruption sequence in these cases was recorded, and the potential risk factors were analyzed. RESULTS: Postprocedural amniotic band disruption sequence was detected, at birth, in 2.2% (15/672) of twin-twin transfusion syndrome cases treated with fetoscopic laser surgery, in both the recipients (10/15, 67%) and the donors (5/15, 33%). Postprocedural amniotic band disruption sequence primarily affected the lower extremities (11/15, 73%) and, less frequently, the upper extremities (2/15, 13%), both the upper and lower extremities (1/15, 7%), or the umbilical cord (1/15, 7%). Postprocedural amniotic band disruption sequence led to the amputation of toes in 5 of 15 cases (33%) and resulted in fetal demise because of constriction of the umbilical cord in 1 case (7%). The independent risk factors identified for postprocedural amniotic band disruption sequence were lower gestational age at laser surgery (odds ratio per week, 1.43; 95% confidence interval, 1.12-1.79; P=.003) and the presence of postprocedural chorioamniotic membrane separation on antenatal ultrasound examination (odds ratio, 41.66; 95% confidence interval, 5.44-319.25; P<.001). CONCLUSION: The prevalence of postprocedural amniotic band disruption sequence is low, but, when present, it may lead to severe consequences, with amputation of extremities or fetal demise occurring in more than one-third of the cases. Lower gestational age at the time of laser therapy and chorioamniotic membrane separation are independent risk factors for the postprocedural amniotic band disruption sequence.

Perioperative fetal hemodynamic changes in twin-twin transfusion syndrome and neurodevelopmental outcome at two years of age.

OBJECTIVE: To investigate whether perioperative fetal hemodynamic changes in twin-to-twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years. METHODS: Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008-2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley-III cognitive/motor developmental test-score > 2SD below the mean. RESULTS: Long-term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA-PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17-21.05, P = .03), a change from normal umbilical artery pulsatility index (UA-PI) presurgery to UA-PI >p95 postsurgery (OR 4.19; 95% CI: 1.04-16.87, P = .04), a change from normal to MCA-PSV >1.5MoM (OR 4.75; 95% CI: 1.43-15.77, P = .01). CONCLUSION: Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.