Diagnosis and management of selective fetal growth restriction in monochorionic twin pregnancies: A cross-sectional international survey.

OBJECTIVE: To identify current practices in the management of selective fetal growth restriction (sFGR) in monochorionic diamniotic (MCDA) twin pregnancies. DESIGN: Cross-sectional survey. SETTING: International. POPULATION: Clinicians involved in the management of MCDA twin pregnancies with sFGR. METHODS: A structured, self-administered survey. MAIN OUTCOME MEASURES: Clinical practices and attitudes to diagnostic criteria and management strategies. RESULTS: Overall, 62.8% (113/180) of clinicians completed the survey; of which, 66.4% (75/113) of the respondents reported that they would use an estimated fetal weight (EFW) of <10th centile for the smaller twin and an inter-twin EFW discordance of >25% for the diagnosis of sFGR. For early-onset type I sFGR, 79.8% (75/94) of respondents expressed that expectant management would be their routine practice. On the other hand, for early-onset type II and type III sFGR, 19.3% (17/88) and 35.7% (30/84) of respondents would manage these pregnancies expectantly, whereas 71.6% (63/88) and 57.1% (48/84) would refer these pregnancies to a fetal intervention centre or would offer fetal intervention for type II and type III cases, respectively. Moreover, 39.0% (16/41) of the respondents would consider fetoscopic laser surgery (FLS) for early-onset type I sFGR, whereas 41.5% (17/41) would offer either FLS or selective feticide, and 12.2% (5/41) would exclusively offer selective feticide. For early-onset type II and type III sFGR cases, 25.9% (21/81) and 31.4% (22/70) would exclusively offer FLS, respectively, whereas 33.3% (27/81) and 32.9% (23/70) would exclusively offer selective feticide. CONCLUSIONS: There is significant variation in clinician practices and attitudes towards the management of early-onset sFGR in MCDA twin pregnancies, especially for type II and type III cases, highlighting the need for high-level evidence to guide management.

Cardiac adaptation and malformation in twin-twin transfusion syndrome and selective fetal growth restriction: A systematic review.

OBJECTIVES: This systematic review explores cardiac adaptation in monochorionic (MC) twins with twin-twin transfusion syndrome (TTTS) or selective fetal growth restriction (sFGR) and assesses the risk of congenital heart defects (CHDs). METHODS: Adhering to PRISMA guidelines, 63 studies were reviewed (49 on cardiac adaptation, 13 on CHD, one on both). A narrative synthesis of cardiac adaptation patterns was performed. Additionally, a meta-analysis compared the livebirth prevalence of CHD in TTTS and sFGR against uncomplicated MC twins. RESULTS: In TTTS recipients, cardiac function may be impaired for diastolic, systolic, as well as global functions, while in donors, cardiac function is generally preserved. In sFGR, large twins may show hypertrophic cardiomyopathy, and small twins may show impaired systolic function. Co-occurrence of TTTS and sFGR magnifies cardiac impact but is often underreported. Meta-analysis for CHD prevalence revealed a relative risk ratio of 3.5 (95% CI: 2.5-4.9) for TTTS and 2.2 (95%CI: 1.3-3.5) for sFGR compared with uncomplicated MC twins. CONCLUSIONS: This study highlights the well-documented cardiac adaptation in TTTS, contrasting with limited understanding in sFGR. Elevated CHD risks were observed in both conditions. Enhanced cardiovascular surveillance is warranted in complicated MC twin pregnancies. Future research should explore cardiac adaptation in sFGR and its long-term consequences.

Length of hysterotomy for fetal spina bifida repair is associated with prematurity risk.

OBJECTIVE: To investigate whether prenatal repair of spina bifida aperta through mini-hysterotomy results in less prematurity, as compared to standard hysterotomy, when adjusting for known prematurity risks. METHODS: We performed a bi-centric, propensity score matched, controlled study, that is, adjusting for factors earlier reported to result in premature delivery or membrane rupture, in consecutive women having prenatal repair either through stapled hysterotomy or sutured mini-hysterotomy (≤3.5 cm). Matches were pairwise compared and cox-regression analysis was performed to define the hazard ratio of delivery <37 weeks. RESULTS: Of 346 meeting the MOMS-criteria, 78 comparable pairs were available for matched-controlled analysis. Mini-hysterotomy patients were younger and had a higher BMI. Mini-hysterotomy was associated with a 1.67-lower risk of delivery <37 weeks (hazard ratio: 0.60; 95% CI: 0.42-0.85; p = 0.004) and 1.72 for delivery <34 + 6 weeks (hazard ratio: 0.58; 95% CI: 0.34-0.97; p = 0.037). The rate of intact uterine scar at birth (mini-hysterotomy: 98.7% vs. hysterotomy: 90.4%; p = 0.070), the rate of reversal of hindbrain herniation within 1 week after surgery (88.9% vs. 97.4%; p = 0.180) and the rate of cerebrospinal fluid leakage (0% vs. 2.7%; p = 0.50) were comparable. CONCLUSION: Prenatal spina bidifa repair through mini-hysterotomy was associated with a later gestational age at delivery and a comparable intact uterus rate without apparent compromise in neuroprotection.

Maternal "mirror" syndrome: Evaluating the benefits of fetal therapy.

OBJECTIVE: To evaluate maternal and perinatal outcomes following fetal intervention in the context of maternal "mirror" syndrome. STUDY DESIGN: A multicenter retrospective study of all cases of fetal hydrops complicated by maternal "mirror" syndrome and treated by any form of fetal therapy between 1995 and 2022. Medical records and ultrasound images of all cases were reviewed. "Mirror" syndrome was defined as fetal hydrops and/or placentomegaly associated with the maternal development of pronounced edema, with or without pre-eclampsia. Fetal hydrops was defined as the presence of abnormal fluid collections in ≥2 body cavities. RESULTS: Twenty-one pregnancies met the inclusion criteria. Causes of fetal hydrops and/or placentomegaly included fetal lung lesions (n = 9), twin-twin transfusion syndrome (n = 6), severe fetal anemia (n = 4), and others (n = 2). Mean gestational age at "mirror" presentation was 27.0 ± 3.8 weeks. Maternal "mirror" syndrome was identified following fetal therapeutic intervention in 14 cases (66.6%). "Mirror" symptoms resolved or significantly improved before delivery in 8 (38.1%) cases with a mean interval from fetal intervention to maternal recovery of 13.1 days (range 4-35). Three women needed to be delivered because of worsening "mirror" syndrome. Of the 21 pregnancies treated (27 fetuses), there were 15 (55.5%) livebirths, 7 (25.9%) neonatal deaths and 5 (18.5%) intra-uterine deaths. CONCLUSION: Following successful treatment and resolution of fetal hydrops, maternal "mirror" syndrome can improve or sometimes completely resolve before delivery. Furthermore, the recognition that "mirror" syndrome may arise only after fetal intervention necessitates hightened patient maternal surveillance in cases of fetal hydrops.

Interventional radiology for prevention and management of postpartum haemorrhage: a single centre retrospective cohort study.

PURPOSE: Postpartum haemorrhage (PPH) remains a leading cause of maternal death despite current medical management. Surgical interventions are still needed for refractory bleeding. Interventional radiology (IR) can be a successful intermediary that avoids the need for hysterectomy. Nevertheless, IR outcome data in a peripartum setting are limited. The objective of this study is to document the efficacy and safety of IR. METHODS: Retrospective study reviewed the records of consecutive patients who underwent peripartum IR from 01/01/2010 until 31/12/2020 in a tertiary academic centre. Patients were divided in a prophylactic and a therapeutic group. Information about interventions before and after IR, and IR specific complications was retrieved. Efficacy was defined by the number of transfusions and additional surgical interventions needed after IR, and safety was assessed by the incidence of IR related complications. RESULTS: Fifty-four patients, prophylactic group (n = 24) and therapeutic group (n = 30), were identified. In both groups, IR was successful with 1.5 ± 2.9 packed cells transfused post-IR (1.0 ± 2.1 prophylactic vs 1.9 ± 3.3 therapeutic; p = 0.261). Additional surgical interventions were required in n = 5 patients (9.2%), n = 1 (4.2%) in the prophylactic vs. n = 4 (13.3%) in the therapeutic group. Complications were reported in n = 12 patients (22.2%), n = 2 (8.3%) prophylactic vs. n = 10 (33.3%) in therapeutic group. Mostly minor complications, as puncture site hematoma or bleeding, were reported in n = 4 (7.4%). Severe complications as necrosis and metabolic complications were reported in n = 2 patients (3.9%). CONCLUSION: IR for prevention and treatment of PPH was highly successful and associated with minor complications.

The Arabin cervical pessary for the prevention of preterm birth in twin-to-twin transfusion syndrome treated by fetoscopic laser coagulation: a multicenter randomized controlled trial.

BACKGROUND: Miscarriage and preterm birth are leading causes of loss and disability in monochorionic twins after laser treatment of twin-twin transfusion syndrome. OBJECTIVE: This study aimed to investigate the use of cervical pessary to reduce preterm birth before 32 weeks of gestation in monochorionic diamniotic twin pregnancies after fetal surgery for twin-twin transfusion syndrome. STUDY DESIGN: In this open-label multicenter randomized trial, pregnant women carrying monochorionic diamniotic twins requiring fetoscopic laser coagulation for twin-twin transfusion syndrome were randomly assigned in a 1:1 ratio to pessary placement or conservative management. The primary outcome was birth before 32 weeks of gestation. The secondary outcomes were birth before 28, 30, 34, or 37 weeks of gestation; preterm premature rupture of membranes; fetal and neonatal survival; and a composite of maternal and neonatal complications. The estimated sample size was 364 patients, with 182 cases in each arm of the study. The analysis was performed according to the intention-to-treat principle. Moreover, 2 interim analyses were planned. RESULTS: The trial was stopped prematurely after the first planned interim analysis for futility. Overall, 137 women were included in the analysis, 67 in the pessary group and 70 in the conservative management group. Preterm birth before 32 weeks of gestation occurred in 27 of 67 women (40.3%) in the pessary group and in 25 of 70 women (35.7%) in the conservative management group (adjusted odds ratio, 1.19; 95% confidence interval, 0.58-2.47; P=.63). No differences between groups was observed in the rate of deliveries before 28, 30, 34, and 37 weeks of gestation. Overall survival to delivery was 91.2% (125/137) for at least 1 twin, and 70.8% (97/137) for both twins, with no difference between groups. Neonatal survival at 30 days was 76.5% (208/272). There was no difference between the groups in maternal or neonatal morbidity. CONCLUSION: In monochorionic diamniotic twin pregnancies requiring fetal therapy for twin-twin transfusion syndrome, routine use of cervical pessary did not reduce the rate of preterm birth before 32 weeks of gestation.

Subsequent fertility, pregnancy, and gynaecological and psychological outcomes after maternal-fetal surgery for open spina bifida: A prospective cohort study.

OBJECTIVE: To determine the medium-term maternal impact of open fetal spina bifida repair. DESIGN: Prospective cohort study. SETTING: University Hospitals Leuven, Belgium. POPULATION: Mothers who had open maternal-fetal spina bifida repair between March 2012 and December 2021. METHODS: A patient-reported survey on subsequent fertility, pregnancy, and gynaecological and psychological outcomes. MAIN OUTCOME MEASURES: Complications during subsequent pregnancies, and gynaecological and psychological problems. RESULTS: Seventy-two out of 100 invited women completed the questionnaire (72%). Despite being advised not to, seven of 13 women attempting to conceive became pregnant within 2 years after fetal surgery and one woman delivered vaginally. Two of the 16 subsequent pregnancies were complicated by an open neural tube defect. One pregnancy was complicated by a placenta accreta and one pregnancy was complicated by a uterine rupture, both with good neonatal outcomes. Nearly half of respondents who did not attempt to conceive reported that this was because of their experience of the index pregnancy and caring for the index child. Three out of four respondents reported medium-term psychological problems, mostly anxiety for the health of the index child, fear for recurrence in subsequent pregnancies and feelings of guilt. CONCLUSIONS: Open maternal-fetal surgery for spina bifida did not appear to affect fertility in our cohort. Half of the attempts to conceive took place within 2 years. One uterine rupture and one placenta accreta occurred in 16 subsequent pregnancies. Most respondents reported psychological problems linked to the index pregnancy, which reinforces the need for long-term psychological support.

Guideline No. 440: Management of Monochorionic Twin Pregnancies.

OBJECTIVE: This guideline reviews the evidence-based management of normal and complicated monochorionic twin pregnancies. TARGET POPULATION: Women with monochorionic twin or higher order multiple pregnancies. BENEFITS, HARMS, AND COSTS: Implementation of these recommendations should improve the management of both complicated and uncomplicated monochorionic (and higher order multiple) twin pregnancies. They will help users monitor monochorionic twin pregnancies appropriately and identify and manage monochorionic twin complications optimally in a timely manner, thereby reducing perinatal morbidity and mortality. These recommendations entail more frequent ultrasound monitoring of monochorionic twins compared to dichorionic twins. EVIDENCE: Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate MeSH headings (Twins, Monozygotic; Ultrasonography, Prenatal; Placenta; Fetofetal Transfusion; Fetal Death; Fetal Growth Retardation). Results were restricted to systematic reviews, randomized controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials. VALIDATION METHODS: The content and recommendations were drafted and agreed upon by the principal authors. The Board of the SOGC approved the final draft for publication. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations). INTENDED AUDIENCE: Maternal-fetal medicine specialists, obstetricians, radiologists, sonographers, family physicians, nurses, midwives, residents, and other health care providers who care for women with monochorionic twin or higher order multiple pregnancies. TWEETABLE ABSTRACT: Canadian (SOGC) guidelines for the diagnosis, ultrasound surveillance and management of monochorionic twin pregnancy complications, including TTTS, TAPS, sFGR (sIUGR), acardiac (TRAP), monoamniotic twins and intrauterine death of one MC twin. SUMMARY STATEMENTS: RECOMMENDATIONS.

Directive clinique no 440 : Prise en charge de la grossesse gémellaire monochoriale.

OBJECTIF: Cette directive clinique passe en revue les données probantes sur la prise en charge de la grossesse gémellaire monochoriale normale et compliquée. POPULATION CIBLE: Les femmes menant une grossesse gémellaire ou multiple de haut rang. BéNéFICES, RISQUES ET COûTS: L'application des recommandations de cette directive devrait améliorer la prise en charge des grossesses gémellaires (ou multiples de haut rang) monochoriales compliquées et non compliquées. Ces recommandations aideront les fournisseurs de soins à surveiller adéquatement les grossesses gémellaires monochoriales ainsi qu'à détecter et prendre en charge rapidement les complications associées de façon optimale afin de réduire les risques de morbidité et mortalité périnatales. Ces recommandations impliquent une surveillance échographique plus fréquente en cas de grossesse monochoriale qu'en cas de grossesse bichoriale. DONNéES PROBANTES: La littérature publiée a été colligée par des recherches dans les bases de données PubMed et Cochrane Library au moyen de termes MeSH pertinents (Twins, Monozygotic; Ultrasonography, Prenatal; Placenta; Fetofetal Transfusion; Fetal Death; Fetal Growth Retardation). Les résultats ont été restreints aux revues systématiques, aux essais cliniques randomisés et aux études observationnelles. Aucune date limite n'a été appliquée, mais les résultats ont été limités aux contenus en anglais ou en français. MéTHODES DE VALIDATION: Les auteurs principaux ont rédigé le contenu et les recommandations et ils se sont entendus sur ces derniers. Le conseil d'administration de la SOGC a approuvé la version définitive aux fins de publication. Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations Assessment, Development and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et conditionnelles [faibles]). PROFESSIONNELS CONCERNéS: Spécialistes en médecine fœto-maternelle, obstétriciens, radiologues, échographistes, médecins de famille, infirmières, sages-femmes, résidents et autres fournisseurs de soins de santé qui s'occupent de femmes menant une grossesse gémellaire ou multiple de haut rang. RéSUMé POUR TWITTER: Directive canadienne (SOGC) pour le diagnostic, la surveillance échographique et la prise en charge des complications de la grossesse gémellaire monochoriale (p. ex., STT, TAPS, retard de croissance sélectif, cojumeau acardiaque, monoamnionicité et mort d'un jumeau). DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

The Management of Acardiac Twinning: Twin Reverse Arterial Perfusion Sequence - An International Survey.

INTRODUCTION: The optimal approach and therapy method for the acardiac twin with a reverse arterial perfusion sequence has not yet been established. The aim of this study was to determine the clinical practice patterns among international fetal therapy units in their management of these cases. METHODS: A survey was sent to fetal centers across the world via email between December 2020 and December 2021. RESULTS: Responses were obtained from 77% contacted centers. The most frequent ultrasound variables used in the evaluation of twin reverse arterial perfusion sequence include echocardiographic assessment of the pump twin and umbilical artery Doppler waveforms in the acardiac and pump twins, in 90% and 80% of the centers, respectively. Most centers in Europe and Latin America propose an in utero intervention in all cases. Most centers in Europe and Latin America prefer interstitial laser ablation, whereas radiofrequency ablation (RFA) is preferred in North America. The earliest gestational age for an intervention is on mean 13 weeks in Europe, which is earlier than the other geographic areas (p = 0.001). CONCLUSIONS: Most centers agreed that antenatal evaluation should include echocardiography along with the UA Doppler waveform measurements, and the most frequently used interventions were interstitial laser ablation or RFA at a median between 14 and 26 weeks.

Pulmonary hypertension in congenital diaphragmatic hernia: Antenatal prediction and impact on neonatal mortality.

OBJECTIVE: To determine the prevalence of pulmonary hypertension (PAH) in left-sided congenital diaphragmatic hernia (CDH); how we could predict it; and how PAH contributed to the model for mortality prediction. STUDY DESIGN: Retrospective analysis in three European centers. The primary outcome was the presence of PAH on postnatal day (d) 1, 7, and at discharge. Studied predictors of PAH were: observed/expected-lung/head-ratio (o/e LHR), liver-herniation, fetoscopic endoluminal tracheal occlusion (FETO), and gestational age (GA) at delivery. The combined effect of pre- and postnatal variables on mortality was modeled by Cox regression. RESULTS: Of the 197 neonates, 56 (28.4%) died. At d1, 67.5% (133/197) had PAH and 61.9% (101/163) by d7. Overall, 6.4% (9/141) had PAH at discharge. At d1, o/e LHR (odds ratio (OR) 0.96) and FETO (OR 2.99) independently correlated to PAH (areas under the curve [AUC]: 0.74). At d7, PAH significantly correlated only with the use of FETO (OR 3.9; AUC: 0.65). None were significant for PAH at discharge. Combining the occurrence of PAH with antenatal biomarkers improved mortality prediction (p = 0.02), in a model including o/e LHR (HR: 0.94), FETO (HR: 0.35), liver herniation (HR: 16.78), and PAH (HR: 15.95). CONCLUSIONS: Antenatal prediction of PAH was only moderate. The postnatal occurrence of PAH further increases the risk of death. Whereas this may be used to counsel parents in the postnatal period, our study demonstrates there is a need to find more accurate antenatal predictors for PAH.

Prenatal cerebellar growth is altered in congenital diaphragmatic hernia on ultrasound.

OBJECTIVE: Children with congenital diaphragmatic hernia (CDH) are at risk for neurodevelopmental delay. Herein we report on prenatal changes in biometry and brain perfusion in fetuses with isolated CDH. STUDY DESIGN: This retrospective study evaluated fetuses with isolated, left-sided CDH in three European referral centers. Abdominal circumference (AC), femur length (FL), head circumference (HC), transcerebellar diameter (TCD), middle cerebral artery (MCA) Doppler, and ventricular width (VW) were assessed during four gestational periods (<24 weeks, 25-28 weeks, 29-32 weeks, >33 weeks). Z-scores were calculated, and growth curves were created based on longitudinal data. RESULTS: In 367 fetuses, HC, AC and FL were within normal ranges throughout gestation. The TCD diminished with advancing gestational age to fall below the fifth percentile after 32 weeks. A less pronounced but similar trend was seen in VW. The peak systolic velocity of the MCA was consistently approximately 10% lower than normal. Disease severity was correlated to TCD (p = 0.002) and MCA doppler values (p = 0.002). There were no differences between fetuses treated with FETO and those managed expectantly. CONCLUSION: Fetuses with isolated left-sided CDH have a small cerebellum and reduced MCA peak systolic velocity. Follow up studies are necessary to determine the impact of these changes on neurodevelopment.

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.

How to Better Distinguish between Type II and III Selective Fetal Growth Restriction in Monochorionic Twin Pregnancies?

OBJECTIVES: The objective of this study is to determine additional variables, next to umbilical artery (UA) Doppler, to help differentiate between Type II and III selective fetal growth restriction (sFGR). METHODS: Retrospective analysis categorizing monochorionic diamniotic twin pregnancies with sFGR and abnormal UA Doppler as either Type II or III sFGR based on the diameter of the artery-to-artery (AA) anastomosis of ≤2 or >2 mm, respectively on placental examination after birth. This exploratory study compared maternal characteristics, pregnancy outcome, placental characteristics, and ultrasound features between the two groups. RESULTS: We included 40 sFGR placentas, 13 were classified as Type II and 27 as Type III. Maternal age was higher in Type II. Small Type II twins had lower birth weights (BWs) for gestational age and BW discordance was higher in Type II. Type III placentas were more unevenly divided, but Type III pairs differed less in BW than expected relative to their placental discordance. Type III placentas more commonly had a vein-to-vein anastomosis and larger artery-to-vein anastomoses than Type II placentas, and proximate cord insertions were only observed in Type III. On the ultrasound scan at first diagnosis, small Type II twins were more growth-restricted. An AA anastomosis was detected in half of the Type III cases and in none of the Type II group. Signs of high-output cardiac strain were observed only in large Type III twins. In contrast, placental dichotomy was detected in nearly half of the Type II cases and only one Type III case. CONCLUSIONS: The presence of an AA anastomosis, signs of cardiac strain in the large twin, and proximate cord insertions suggested Type III sFGR, whereas placental dichotomy and a severe growth restriction were typically present in Type II. Prospective studies need to validate if these markers help prenatal differentiation between Type II and III sFGR.

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.

Intrauterine fetoscopic laser surgery versus expectant management in stage 1 twin-to-twin transfusion syndrome: an international randomized trial.

BACKGROUND: Selective fetoscopic laser coagulation of the intertwin anastomotic chorionic vessels is the first-line treatment for twin-twin transfusion syndrome. However, in stage 1 twin-twin transfusion syndrome, the risks of intrauterine surgery may be higher than those of the natural progression of the condition. OBJECTIVE: This study aimed to compare immediate surgery and expectant follow-up in stage 1 twin-twin transfusion syndrome. STUDY DESIGN: We conducted a multicentric randomized trial, which recruited from 2011 to 2018 with a 6-month postnatal follow-up. The study was conducted in 9 fetal medicine centers in Europe and the Unites States. Asymptomatic women with stage 1 twin-twin transfusion syndrome between 16 and 26 weeks' gestation, a cervix of >15 mm, and access to a surgical center within 48 hours of diagnosis were randomized between expectant management and immediate surgery. In patients allocated to immediate laser treatment, percutaneous laser coagulation of anastomotic vessels was performed within 72 hours. In patients allocated to expectant management, a weekly ultrasound follow-up was planned. Rescue fetoscopic coagulation of anastomoses was offered if the syndrome worsened as seen during a follow-up, either because of progression to a higher Quintero stage or because of the maternal complications of polyhydramnios. The primary outcome was survival at 6 months without severe neurologic morbidity. Severe complications of prematurity and maternal morbidity were secondary outcomes. RESULTS: The trial was stopped at 117 of 200 planned inclusions for slow accrual rate over 7 years: 58 women were allocated to expectant management and 59 to immediate laser treatment. Intact survival was seen in 84 of 109 (77%) expectant cases and in 89 of 114 (78%) (P=.88) immediate surgery cases, and severe neurologic morbidity occurred in 5 of 109 (4.6%) and 3 of 114 (2.6%) (P=.49) cases in the expectant and immediate surgery groups, respectively. In patients followed expectantly, 24 of 58 (41%) cases remained stable with dual intact survival in 36 of 44 (86%) cases at 6 months. Intact survival was lower following surgery than for the nonprogressive cases, although nonsignificantly (78% and 71% following immediate and rescue surgery, respectively). CONCLUSION: It is unlikely that early fetal surgery is of benefit for stage 1 twin-twin transfusion syndrome in asymptomatic pregnant women with a long cervix. Although expectant management is reasonable for these cases, 60% of the cases will progress and require rapid transfer to a surgical center.

Spontaneous twin anemia polycythemia sequence: diagnosis, management, and outcome in an international cohort of 249 cases.

BACKGROUND: Twin anemia polycythemia sequence is a chronic form of unbalanced fetofetal transfusion through minuscule placental anastomoses in monochorionic twins, leading to anemia in the donor and polycythemia in the recipient. Owing to the low incidence of twin anemia polycythemia sequence, data on diagnosis, management, and outcome are limited. OBJECTIVE: This study aimed to investigate the diagnosis, management, and outcome in a large international cohort of spontaneous twin anemia polycythemia sequence. STUDY DESIGN: Data from the international twin anemia polycythemia sequence registry, retrospectively collected between 2014 and 2019, were used for this study. A total of 17 fetal therapy centers contributed to the data collection. The primary outcomes were perinatal mortality and severe neonatal morbidity. Secondary outcomes included a risk factor analysis for perinatal mortality and severe neonatal morbidity. RESULTS: A total of 249 cases of spontaneous twin anemia polycythemia sequence were included in this study, 219 (88%) of which were diagnosed antenatally and 30 (12%) postnatally. Twin anemia polycythemia sequence was diagnosed antenatally at a median gestational age of 23.7 weeks (interquartile range, 9.7-28.8; range, 15.1-35.3). Antenatal management included laser surgery in 39% (86 of 219), expectant management in 23% (51 of 219), delivery in 16% (34 of 219), intrauterine transfusion (with partial exchange transfusion) in 12% (26 of 219), selective feticide in 8% (18 of 219), and termination of pregnancy in 1% (3 of 219) of cases. Perinatal mortality rate was 15% (72 of 493) for the total group, 22% (54 of 243) for donors, and 7% (18 of 242) for recipients (P<.001). Severe neonatal morbidity occurred in 33% (141 of 432) of twins with twin anemia polycythemia sequence and was similar for donors (32%; 63 of 196) and recipients (33%; 75 of 228) (P=.628). Independent risk factors for spontaneous perinatal mortality were donor status (odds ratio, 3.8; 95% confidence interval, 1.9-7.5; P<.001), antenatal twin anemia polycythemia sequence stage (odds ratio, 6.3; 95% confidence interval, 1.4-27.8; P=.016 [stage 2]; odds ratio, 9.6; 95% confidence interval, 2.1-45.5; P=.005 [stage 3]; odds ratio, 20.9; 95% confidence interval, 3.0-146.4; P=.002 [stage 4]), and gestational age at birth (odds ratio, 0.8; 95% confidence interval, 0.7-0.9; P=.001). Independent risk factors for severe neonatal morbidity were antenatal twin anemia polycythemia sequence stage 4 (odds ratio, 7.9; 95% confidence interval, 1.4-43.3; P=.018) and gestational age at birth (odds ratio, 1.7; 95% confidence interval, 1.5-2.1, P<.001). CONCLUSION: Spontaneous twin anemia polycythemia sequence can develop at any time in pregnancy from the beginning of the second trimester to the end of the third trimester. Management for twin anemia polycythemia sequence varies considerably, with laser surgery being the most frequent intervention. Perinatal mortality and severe neonatal morbidity were high, the former especially so in the donor twins.

The prevalence of brain lesions after in utero surgery for twin-to-twin transfusion syndrome on third-trimester MRI: a retrospective cohort study.

OBJECTIVE: Due to the increased risk of antenatal brain lesions, we offer a third-trimester magnetic resonance imaging (MRI) scan to all patients who underwent an in utero intervention for twin-twin transfusion syndrome (TTTS). However, the usefulness of such a policy has not been demonstrated yet. Therefore, we determined the prevalence of antenatal brain lesions detected on third-trimester MRI and the proportion of lesions detected exclusively on MRI. MATERIALS AND METHODS: We conducted a retrospective cohort study of monochorionic diamniotic twin pregnancies complicated by TTTS that underwent laser coagulation of the vascular anastomoses or fetal reduction by umbilical cord occlusion between 2010 and 2017. We reviewed the third-trimester MRI findings and compared those with the prenatal ultrasonography. RESULTS: Of the 141 patients treated with laser coagulation and 17 managed by cord occlusion, 112/141 (79%) and 15/17 (88%) patients reached 28 weeks. Of those, 69/112 (62%) and 11/15 (73%) underwent an MRI between 28 and 32 weeks. After laser coagulation, MRI detected an antenatal brain lesion in 6 of 69 pregnancies (9%) or in 6 of 125 fetuses (5%). In 4 cases (67%), the lesion was detected only on MRI. In the 11 patients treated with cord occlusion, no brain lesions were diagnosed. CONCLUSION: The prevalence of brain lesions detected by third-trimester MRI is higher compared to prenatal ultrasonography alone, making MRI a useful adjunct to detect antenatal brain lesions in twin pregnancies after in utero treatment for TTTS. KEY POINTS: • In utero interventions for twin-to-twin transfusion syndrome (TTTS) do not prevent the occurrence of antenatal brain lesions. • Fetal magnetic resonance imaging (MRI) has high accuracy in detecting anomalies of cortical development and can be a useful adjunct to ultrasonography in diagnosing certain brain abnormalities. • After laser coagulation of the anastomoses for TTTS, third-trimester MRI diagnosed a brain lesion that was not detected earlier on ultrasound scan in 6% of pregnancies.

The Detection, Outcome, and Presentation of Twin-Twin Transfusion Syndrome in Monochorionic Diamniotic Twin Pregnancies Followed with a Protocol of Fortnightly Ultrasound Examination.

BACKGROUND: Evidence to support a fortnightly scan protocol for monochorionic diamniotic (MCDA) pregnancies to detect twin-twin transfusion syndrome (TTTS) is scarce. Also, TTTS-related mortality in an unselected cohort is not well documented. Finally, common knowledge suggests that a more frequent follow-up may pick up the disease at a milder stage, but little is known on the ultrasound findings before the diagnosis. OBJECTIVES: We examine if a fortnightly ultrasound scan from 16 weeks onward detects TTTS in time. Also, we document the outcomes in a large unselected cohort of MCDA twins and examine the ultrasound findings within 14 days before diagnosis. METHODS: Retrospective cohort of 675 MCDA twin pregnancies followed with a fortnightly scan protocol from 16 weeks onward. Timely detection of TTTS was defined as before fetal demise (stage V), ruptured membranes, or a dilated cervix. We compared the ultrasound findings before the diagnosis between stage I-II and stage III-IV. RESULTS: A total of 82/675 (12%) pregnancies developed TTTS, of which 74/82 (90%) were detected in time. In 8/82 (10%), TTTS was diagnosed in stage V: 5 before 16 weeks and 2 after 26 weeks. Fetoscopic laser photocoagulation (FLP) of the placental anastomoses was performed in 48/82 (59%). The survival of TTTS in the entire cohort was 105/164 (64%). In contrast, survival after FLP was 77/96 (80%). In 16/19 (84%) of stage III-IV TTTS, abnormal Doppler findings preceded the diagnosis of TTTS. CONCLUSIONS: A scheme of fortnightly ultrasound scans from 16 weeks onward detects 9 out of ten TTTS pregnancies in time. Most stage V cases presented outside the typical time window of 16 and 26 weeks. Survival rates after FLP underestimate the mortality of TTTS. Most stage III-IV cases have abnormal Doppler findings before the diagnosis of TTTS.

Monochorionic diamniotic twins: What do I tell the prospective parents?

Monochorionic diamniotic twins occur in about 1 in 300 pregnancies. Compared with dichorionic twins, they face increased risks because of the shared circulation. In about 15%, an imbalance in blood exchange occurs, such as twin-twin transfusion syndrome and twin anemia polycythemia sequence. In this review, we summarize the latest evidence on the management of monochorionic diamniotic twin pregnancies and their specific complications, with a focus on information that is relevant for prospective parents.