Pregnancy and infant outcome of 80 consecutive cord coagulations in complicated monochorionic multiple pregnancies

Short- and Long-Term Outcome of Selective Reduction by Fetoscopy-Guided Bipolar Cord Coagulation in Monochronic Twin Pregnancies

INTRODUCTION

The aim of this study was to assess the short- and long-term outcome of selective reduction by fetoscopy-guided bipolar cord coagulation in monochronic twin pregnancies.

METHODS

Retrospective analysis was conducted of a consecutive cohort of all monochorionic twin pregnancies treated with fetoscopy-guided bipolar cord coagulation between December 2015 and December 2022 in a single center in China.

RESULTS

A total of 43 monochronic twin pregnancies undergoing fetoscopy-guided bipolar cord coagulation were analyzed. There were 5 intrauterine deaths with an 88.4% (38/43) survival rate overall. The preterm premature rupture of the membranes rate was 13.2%, and the preterm birth before 37 and 32 weeks was 42.1% and 13.1%, respectively. An uptrend in the survival rate (78.9 vs. 95.8%, p = 0.086) and a downtrend of procedure time (30 vs. 16.5 min, p = 0.036) were observed over time (period 1 from December 2015 to December 2019 verses period 2 from January 2020 to December 2022). Long-term outcome was assessed in 94.6% (35/37) of survivors, and 91.4% (32/35) had normal neurodevelopmental outcome.

CONCLUSION

Fetoscopy-guided bipolar cord coagulation for fetal reduction in complicated monochorionic twin pregnancies could achieve a favorable short- and long-term outcome, especially in experienced hands.

Outcome of Monochorionic Diamniotic Twins with Twin Reversed Arterial Perfusion Sequence: Interstitial Laser versus Endoscopic Cord Occlusion

Twin reversed arterial perfusion sequence (TRAP) is a rare complication of monochorionic twins (MC). This study aimed to describe and compare the short- and long-term outcomes of MC pregnancies with the TRAP sequence treated with two different techniques: interstitial fetal laser (IFL) (n = 22) versus endoscopic cord occlusion (CO) (n = 24). The study population included 46 MC pregnancies with TRAP. Pregnancy loss within 2 weeks after the procedure occurred in 27% of cases (6/22) in the group treated with IFL and in 8% of cases (2/24) in the group treated with CO. The survival rate of the pump twin was 73% (16/22) in the IFL group and 83% (20/24) in the group treated with CO. The median gestational age at birth was 38 weeks in the group treated with IFL and 35 weeks in the group treated with CO. The rate of preterm birth before 34 weeks was 12.5% (2/16) in the group treated with IFL and 32% (7/22) in the group treated with CO. In the group treated with IFL, there were no cases of neurological disabilities reported by the parents compared to three cases in the CO group. IFL is associated with a higher risk of early pregnancy loss; however, if the pregnancy progresses, it is associated with lower risks of preterm birth and neurological disabilities in the survivors.

The High-Risk Profile of Selective Growth Restriction in Monochorionic Twin Pregnancies

The present review aims to provide a critical appraisal of the sonographic diagnosis and follow-up and to evaluate the optimal clinical management of monochorionic twin pregnancies where one of the twins is complicated by selective fetal growth restriction (sFGR). The classification is based on the umbilical artery (UA) diastolic flow reflecting the outcome. If the sFGR twin has positive diastolic flow (Type I) then the prognosis is good, and it does not require close surveillance. Biweekly or weekly sonographic and Doppler surveillance and fetal monitoring are recommended strategies to detect unpredictable complications in type II and type III forms, which are defined by persistently absent/reverse end-diastolic flow (AREDF) or cyclically intermittent absent/reverse end-diastolic flow (iAREDF) in the umbilical waveforms, respectively. The latest forms are associated with an increased risk of unexpected fetal demise of the smaller twin and 10-20% risk of neurological injury in the larger twin in addition to the overall risk of prematurity. The clinical course can be affected by elective fetal therapy ('dichorinization' of the placenta with laser or selective fetal reduction) or elective delivery in the presence of severe fetal deterioration. The prediction of the clinical outcome in complicated cases of type II and III sFGR cases remains elusive. Novel routines in fetal and placental scans in order to predict neurological impairments and unexpected fetal death to optimize the delivery time-point are needed.

Fetoscopic laser surgery for twin-to-twin transfusion syndrome in DCTA triplets compared to MCDA twins: collaborative study and literature review

OBJECTIVE

To compare the outcomes of dichorionic triamniotic (DCTA) triplets with that of monochorionic diamniotic (MCDA) twin gestations undergoing fetoscopic laser surgery (FLS) for treatment of twin-to-twin transfusion syndrome (TTTS).

METHODS

Retrospective cohort study of prospectively collected data of consecutive DCTA triplet and MCDA twin pregnancies with TTTS that underwent FLS at two fetal treatment centers between 2012 and 2020. Preoperative, operative and, postoperative variables were collected. Perinatal outcomes were investigated. Primary outcome was survival to birth and to neonatal period. Secondary outcomes were gestational age (GA) at birth and procedure-to-delivery interval. Literature review was conducted in which PubMed, Web of Science, and Scopus were searched from inception to September, 2020.

RESULTS

Twenty four sets of DCTA triplets were compared to MCDA twins during the study period. There were no significant differences in survival (no survivor, single, or double survivors) to birth and to the neonatal period of the MC twin pairs of the DCTA triplets vs MCDA twins. Median GA at delivery was approximately three weeks earlier in DCTA triplets compared to MCDA twins (28.4 weeks vs 31.4 weeks, p = .035, respectively). Rates of preterm birth (PTB) less than 32 and less than 28 weeks were significantly higher in DCTA triplets compared to twins (<32 weeks: 70.8% vs 51.1%, p = .037, respectively, and <28 weeks: 37.5% vs 20.8%, p = .033, respectively).

CONCLUSION

Perinatal survival including fetal and neonatal are comparable between DCTA triplets and MCDA twins. However, this might have resulted from the small sample size of the DCTA triplets. GA at delivery is earlier in triplets, which could be due to the nature of triplet gestation rather than to the laser procedure itself.

Perinatal and neurodevelopmental outcome in complicated monochorionic pregnancy after selective fetal reduction: radiofrequency ablation vs microwave ablation

OBJECTIVES

To summarize our experience in the application of radiofrequency ablation (RFA) and microwave ablation (MWA) for selective fetal reduction in complicated monochorionic pregnancies and compare the perinatal outcome of the two techniques.

METHODS

This was a retrospective study of data from a consecutive cohort of all monochorionic twin pregnancies that underwent selective fetal reduction with RFA or MWA at Peking University Third Hospital, Beijing, China from January 2012 to December 2018. All surviving cotwins were followed up to assess their neurodevelopment using the Age &amp; Stage Questionnaire, Chinese version. Perinatal and neurodevelopmental outcomes were compared between the RFA and MWA groups. We also fitted multivariable models to test the association between procedure-related factors and the main perinatal outcomes, including preterm birth (PTB) &lt; 37 weeks' gestation, intrauterine fetal death (IUFD) of the cotwin, adverse outcome (defined as occurrence of IUFD of the cotwin, termination of pregnancy or PTB &lt; 28 weeks) and overall survival.

RESULTS

In total, 45 cases (42 twin and three triplet pregnancies) underwent RFA and 126 cases (105 twin and 21 triplet pregnancies) underwent MWA. The overall survival rates in monochorionic diamniotic twin pregnancies were similar between the RFA and MWA groups (61.0% vs 67.0%; P = 0.494). However, pregnancies whose indication for fetal reduction was selective intrauterine growth restriction or twin reversed arterial perfusion had higher overall survival rates (75.5% and 82.6%, respectively) compared with those in other indication groups. A total of 104 children were followed up (20 in the RFA group and 84 in the MWA group); four (20.0%) and eight (9.5%) children were assessed as having overall developmental delay in the RFA and MWA groups, respectively, with no significant difference between the two groups. Multivariable analyses showed that procedure indication, number of ablation cycles and gestational age at procedure were associated significantly with the main perinatal outcomes.

CONCLUSIONS

RFA and MWA for selective fetal reduction in complicated monochorionic pregnancies can achieve similar overall survival rate and neurodevelopmental outcome, but MWA is associated with a lower risk of preterm birth. Moreover, procedure-related factors are associated significantly with perinatal outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Selective reduction in complicated monochorionic pregnancies: a systematic review and meta-analysis of different techniques

OBJECTIVE

This systematic review and meta-analysis aimed to compare the perinatal outcomes of complicated monochorionic pregnancies after selective reduction by radiofrequency ablation, bipolar cord coagulation, and interstitial laser.

DATA SOURCES

We searched PubMed, Scopus, and Web of Science, from the inception of the database up to April 26, 2021.

STUDY ELIGIBILITY CRITERIA

Studies comparing at least 2 selective reduction techniques among complicated monochorionic pregnancies and presenting data on perinatal outcomes, including gestational age at procedure, gestational age at delivery, procedure to delivery interval, preterm premature rupture of membranes, preterm birth, survival rate, and birthweight, were eligible.

METHODS

The random-effects model was used to pool the mean differences or odds ratios and corresponding 95% confidence intervals. Heterogeneity was assessed using the I² value.

RESULTS

A total of 10 studies with 734 cases of fetal reduction met the inclusion criteria, of which 9 studies with 674 fetuses were eligible for quantitative synthesis. In 8 studies that compared radiofrequency ablation with bipolar cord coagulation, radiofrequency ablation was associated with increased procedure to delivery interval (days) (mean difference, 13.42; 95% confidence interval, 1.90-24.94; P=.02; I²=0.0%), decreased preterm birth (odds ratio, 0.50; 95% confidence interval, 0.29-0.85; P=.01; I²=3.0%), and decreased preterm premature rupture of membranes (odds ratio, 0.45; 95% confidence interval, 0.27-0.73; P=.001; I²=0.0%). Radiofrequency ablation and bipolar cord coagulation had comparable survival rates (odds ratio, 0.85; 95% confidence interval, 0.54-1.35; P=.49; I²=0.0%). In 3 studies that compared radiofrequency ablation with interstitial laser, there was no significant difference in gestational age at delivery (P=.07) or survival (P=.15). In 3 studies that compared bipolar cord coagulation with interstitial laser, bipolar cord coagulation was associated with a higher survival rate (odds ratio, 3.21; 95% confidence interval, 1.13-9.10; P=.03; I²=0.0%), but the gestational age at delivery was comparable between groups (P=.16).

CONCLUSION

This study demonstrated that radiofrequency ablation has a greater procedure to delivery interval and decreased preterm premature rupture of membranes and preterm birth than bipolar cord coagulation. Although there was no difference in gestational age at delivery for either bipolar cord coagulation, radiofrequency ablation, or interstitial laser, survival was higher with bipolar cord coagulation than with interstitial laser.

Twin reverse arterial perfusion: Timing of intervention

Twin reverse arterial perfusion (TRAP) sequence is a severe anomaly in monochorionic twins where one twin has profound corporeal underdevelopment and acardia. The normal "pump" co-twin provides blood flow to the acardiac twin through placental anastomoses which may lead to cardiac failure and pump twin demise as well as preterm delivery from severe polyhydramnios. Treatments include radiofrequency ablation, bipolar cord coagulation, and intrafetal laser with each aimed at occluding blood flow to the acardiac twin. However, none of these modalities has proven superior in terms of either pump twin survival or minimization of complications, including preterm premature rupture of membranes, preterm birth, or unexpected co-twin demise. The optimal timing of treatment is also unknown, without clear indications for intervention versus expectant management. Very early treatment of TRAP (i.e., <16 weeks) has been proposed to reduce first-trimester demise; however, this approach remains experimental. Further investigation is required to determine the best treatment and timing of intervention for TRAP.

Outcome of Monochorionic Pregnancies after Selective Feticide with Bipolar Cord Coagulation: A German Single Center Experience

Objectives: To review the outcome of complicated monochorionic pregnancies after fetoscopic selective feticide with bipolar cord coagulation in an experienced German center. Methods: All cases that underwent selective feticide using fetoscopic bipolar umbilical cord occlusion (and simultaneous dissection in monoamniotics) at the University of Bonn in the past 10 years were retrospectively analyzed for antenatal and neonatal course and outcome. An adverse outcome was defined as either intrauterine death (IUD), neonatal death (NND), preterm prelabour rupture of membranes (PPROM), or preterm delivery (PTD) before 32.0 weeks of gestation. Results: We diagnosed 56 monochorionic pregnancies, including 43 diamniotic and 8 monoamniotic twins, as well as 5 triplets, complicated by discordant fetal anomalies (n = 10), selective intrauterine growth restriction (n = 29), twin-to-twin transfusion syndrome (n = 13), twin reversed arterial perfusion sequence (n = 3), or severe early twin anemia polycythemia sequence (n = 1), that underwent fetoscopic selective feticide in the 10 years study period. Selective feticide was performed by bipolar cord coagulation at a median gestational age of 21.2 weeks. PPROM occurred in 11 cases, 7 (12.5%) before 32.0 weeks and 4 (7.1%) between 34.0 and 36.0 weeks, respectively. There were five (8.9%) co-twins IUDs at a median of 2 weeks after the intervention. We observed 12 (21.4%) PTDs before 32.0 weeks of gestation and 2 (3.6%) NNDs. Mean gestational age at delivery was 37.1 weeks, with an overall survival of the co-twin of 87.5%. Conclusion: In experienced hands, fetoscopic selective feticide is an effective treatment in complicated monochorionic pregnancies. By sacrificing a sick fetus that jeopardizes the entire pregnancy, a higher survival rate of the co-twin can be achieved.

Outcome of Monochorionic Monoamniotic Twin Reversed Arterial Perfusion Sequence Diagnosed in the First Trimester

INTRODUCTION

The aim of this study is to evaluate the outcome of pregnancies complicated by monochorionic monoamniotic twin reversed arterial perfusion sequence (MOMA TRAP) diagnosed in the first trimester.

METHODS

All patients diagnosed with MOMA TRAP sequence <14.0 weeks of gestation in a 10-year study period were retrospectively analyzed for intrauterine course and outcome. All patients were offered either expectant management or intrauterine intervention. Adverse outcome was defined as either intrauterine death (IUD), neonatal death or preterm birth <34.0 weeks of gestation.

RESULTS

In the study period, 17 cases with MOMA TRAP sequence were diagnosed. Of these, 2 couples opted for termination of pregnancy. The remaining 15 were divided into 2 groups depending on the management: group A (n = 8) with expectant management and group B (n = 7) with intrauterine intervention. All fetuses in group A died before 20 weeks. Survival in group B was significantly better with 4/7 (57.1%) life births at a median of 39.6 weeks of gestation (p = 0.0256). The reasons for IUD in the 3 cases in group B were hemodynamic, strangulation, and bleeding complications during intervention.

CONCLUSIONS

Intrauterine intervention in MOMA TRAP pregnancies significantly improves neonatal survival, although it is still associated with a substantial risk for IUD by hemodynamic complications or entanglement.

Perinatal outcomes after selective feticide via umbilical cord occlusion in complicated monochorionic pregnancies: A systematic review and meta-analysis

OBJECTIVE

We aimed to compare perinatal outcomes between umbilical cord occlusion techniques in monochorionic pregnancies, including umbilical cord ligation, fetoscopic laser coagulation, interstitial laser coagulation, bipolar cord occlusion, radiofrequency ablation, and microwave ablation.

METHODS

This study was registered with PROSPERO (CRD42020158861). PubMed, Web of Science, Cochrane Library, and Embase were searched for studies published up to May 2020. The DerSimonian-Laird random-effects model was used for the meta-analysis. Subgroup analyses were performed to compare the outcomes among the six techniques. Meta-regression was used to adjust for confounders.

RESULTS

Thirty-four studies with 1646 participants were included. The overall survival was 76.5% after umbilical cord ligation, 78.8% after fetoscopic laser coagulation, 60.3% after interstitial laser coagulation, 79.2% after bipolar cord occlusion, 77.5% after radiofrequency ablation, and 75.0% after microwave ablation. Subgroup comparison showed the rates of overall survival and preterm premature rupture of membranes were not significant different among six techniques. However, rates of fetal loss, premature birth, live birth, and neonatal death differed significantly among the six groups.

CONCLUSIONS

The choice of umbilical cord occlusion techniques will affect perinatal outcomes. We suggested that the choice of umbilical cord occlusion techniques should fully consider these differences among techniques.

Monochorionic diamniotic twin pregnancies

About one in five twin pregnancies are monochorionic diamniotic. In these twins, transfusion imbalances may develop due to the invariably present vascular anastomoses. The most severe imbalance is twin-twin transfusion syndrome, which presents as a significant amniotic fluid difference diagnosed on ultrasound scan, usually before 26 weeks. Another transfusion imbalance is twin anemia polycythemia sequence, a severe hemoglobin difference occurring mainly after 26 weeks in previously uncomplicated pregnancies. Fetoscopic laser coagulation of the anastomoses addresses the cause of these transfusion imbalances. Besides transfusion imbalances, the monochorionic placenta may be unevenly divided, or one part may be dysfunctional, leading to an intertwin growth difference of more than 20%. Here, laser ablation of the anastomoses will usually not cure the problem but aims to protect the appropriately growing twin if the growth-restricted co-twin dies. In monochorionic twins, structural anomalies are twice as common as in singleton pregnancies, probably due to a teratogenic effect of the embryonic splitting or because of transfusion imbalances. In contrast, chromosomal anomalies appear less common, possibly because they more likely result in an early demise. Selective reduction is feasible in monochorionic pregnancies but carries increased risks of loss, miscarriage, and early birth than a selective reduction in a dichorionic setting. Finally, if one monochorionic twin dies spontaneously, its co-twin may acutely exsanguinate into the demised co-twin, which may result in the loss of both twins or brain damage in the surviving twin. This update addresses the pathophysiology, diagnosis, and management of these common complications in monochorionic diamniotic twin pregnancies.

Long-term neurodevelopmental outcomes of the pump twin in twin reversed arterial perfusion sequence treated by radiofrequency ablation

Objectives

To assess long‐term neurodevelopmental outcomes in children after radiofrequency ablation (RFA) for twin reversed arterial perfusion (TRAP) sequence.

Methods

This cross‐sectional study included children who underwent RFA for the TRAP sequence between 2012 and 2018. We assessed neurodevelopment in children using the Kinder Infant Development Scale, a validated questionnaire. The developmental quotient (DQ) assessed in nine subscales was calculated as the developmental age divided by the chronological age. Neurodevelopmental delay (NDD) was defined as a DQ of <70 points.

Results

In total, 38 children from 37 pregnancies underwent RFA for the TRAP sequence during the study period; 6 fetuses died in utero. We sent the questionnaire to the parents of the 32 surviving children and obtained answers for 27 (84%). The median age at the assessment was 2 years and 5 months old. The median total DQ was 111 (80–150). Most median DQs in the nine subscales were above 70. The incidence of NDD was 0% (0/27). There were no marked differences in DQ by chorionicity.

Conclusions

Children who survived after RFA for TRAP sequence showed favorable long‐term neurodevelopmental outcomes. Radiofrequency ablation seems to rarely affect fetal neurodevelopment. Pregnant women with TRAP sequence are encouraged to be treated by RFA.

What's already known about this topic?

Radiofrequency ablation (RFA), which induces the coagulation of tissue, is commonly used to treat twin reversed arterial perfusion (TRAP) sequence because of the minimal invasiveness of the technique.

The survival rate of the pump twin of TRAP sequence treated by RFA is more than 80%; however, the long‐term neurodevelopmental outcomes of survivors have rarely been investigated.

What does this study add?

Pump twins of TRAP sequence who survived after RFA showed favorable long‐term neurodevelopmental outcomes with a median developmental quotient of more than 100.

Radiofrequency ablation in fetal surgery itself seems to rarely affect fetal neurodevelopment.

Fetoscopy-guided bipolar cord coagulation in selective fetal reduction with complicated monochorionic diamniotic twins: a prospective cohort study

OBJECTIVE

To assess the feasibility of fetoscopy-guided bipolar umbilical cord coagulation for selective fetal reduction in complicated monochorionic diamniotic (MCDA) twin pregnancies.

METHODS

MCDA twins undergoing fetoscopy-guided bipolar cord coagulation (BCC) were enrolled prospectively between December 2015 to March 2020 in a fetal medicine center.

RESULTS

Twenty-three cases undergoing fetoscopy-guided BCC were finally analyzed, including 11 cases for type 2 selective intrauterine growth restriction, 4 cases for twin-twin transfusion syndrome, and 8 cases for a severe discordant anomaly. The overall survival rate was 78.3% (18/23).

CONCLUSIONS

Fetoscopy-guided BCC is effective for selective fetal reduction in complicated monochorionic twin pregnancies.

Screening, Management and Delivery in Twin Pregnancy

The following AWMF guideline (DGGG/AGG & DEGUM responsible) deals with the diagnosis, screening and management of twins as well as the timing and mode of birth.Twin pregnancies can be classified as dichorionic diamniotic (DC DA), monochorionic diamniotic (MC DA) and monochorionic monoamniotic (MC MA) which are always monochorionic.Twin pregnancies can be concordant (both twins are affected) or discordant (only one twin is affected) for chromosomal defects, malformations, growth restriction and hemodynamic disorders.Chorionicity is the prognostically most significant parameter. Monochorial twins have significantly higher risks of intrauterine morbidity and mortality compared to dichorial twins.In particular, general aspects of twin pregnancies such as dating, determination of chorionicity and amnionicity, the labeling of twin fetuses and the perinatal switch phenomenon are discussed.Routine monitoring of MC and DC twin pregnancies with ultrasound at 11-13^+ 6 weeks of gestation for chromosomal defects, invasive prenatal diagnosis, first-trimester NT or CRL discrepancies, early diagnosis of fetal anatomical defects, and management of twins with abnormalities, including selective fetocide, is described.Second trimester screening and management for preterm birth, intrauterine selective growth restriction (sFGR), classification of monochorial twins with sFGR, and management of the surviving twin after the death of the co-twin are described.Complications exclusively affecting MC twins include Twin to Twin Transfusion Syndrome (TTTS) with the important topics screening, prognosis, complications of laser therapy, timing of delivery, risks for brain abnormalities and delayed neurological development, Twin Anemia-Polycythemia Sequence (TAPS) and Twin Reversed Arterial Perfusion (TRAP) Sequence. This also includes MC MA twins as well as conjoined twins.Finally, the birth mode and time for DC and MC twin pregnancies are described.The information is summarized in 62 recommendations for action, 4 tables and 8 illustrations with comprehensive background texts.The guideline is an international guideline adaptation (ISUOG, NICE) as well as a systematic literature search and is up-to-date.

Risk Factors Associated with Preterm Prelabor Rupture of Membranes after Cord Occlusion in Monochorionic Diamniotic Twins

INTRODUCTION

Preterm prelabor rupture of membranes (PPROM) is a common complication after fetal surgeries. The aim of this study was to assess risk factors for and outcomes after PPROM following cord occlusion (CO) in monochorionic diamniotic (MCDA) pregnancies.

METHODS

This was a retrospective cohort study of 188 consecutive MCDA pregnancies treated by bipolar or laser CO, either primarily because of discordant malformation (dMF) or severe selective fetal growth restriction (sFGR), or secondarily when complete bichorionization was not possible in case of twin-to-twin transfusion syndrome (TTTS) or sFGR. Intentional septostomy was performed when needed. The procedure-related PPROM was defined as rupture of membranes <32 weeks' gestation (PROM <32 weeks). Selected pre-, intra-, and early postoperative variables were analyzed by univariate and binomial logistic regression to determine they are correlated to PROM <32 weeks after CO.

RESULTS

Between 2006 and 2017, 188 cases underwent CO. Diagnosis was TTTS in 28.2% (n = 53), severe sFGR in 49.5% (n = 93), and dMF in 22.3% (n = 42). PROM <32 weeks occurred in 21.3% (n = 40), resulting in worse perinatal outcomes, as preterm birth <32 weeks occurred in 80.7% (vs. 8.3%, p = 0.000), procedure-to-delivery interval was 47.5 days (vs. 125, p = 0.000), gestational age (GA) at birth 30.0 weeks (vs. 37.7 weeks, p = 0.000), and survival 65.0% (vs. 91.1%, p = 0.000). In univariate analysis, indication, anterior placenta, cervical length, GA at surgery, operation time, amniodistention and drainage fluid volumes, chorioamniotic membrane separation, and septostomy were selected as relevant factors to be included in the regression model. In a multivariate analysis, TTTS was the only factor associated to PROM <32 weeks (OR 3.5 CI 95% 1.5-7.9).

CONCLUSIONS

PROM <32 weeks after CO increases the risk of preterm delivery. In this cohort, the membrane rupture was more likely when CO was done in the context of TTTS.

Controversies in the management of twin pregnancy

Despite many advances in antenatal care, twin pregnancies still experience more adverse outcomes, in particular perinatal morbidity and mortality. They also pose a multitude of challenges and controversies, as outlined in this Review. Moreover, they are less likely to be included in clinical trials. Many issues on classification and management remain under debate. Efforts at standardizing diagnostic criteria, monitoring protocols, management and outcome reporting are likely to reduce their perinatal risks. The top 10 most important research uncertainties related to multiple pregnancies have been identified by both clinicians and patients. More robust research in the form of randomized trials and large well-conducted prospective cohort studies is needed to address these controversies. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Perinatal outcome of monochorionic diamniotic twin pregnancy complicated by selective intrauterine growth restriction according to umbilical artery Doppler flow pattern: single-center study using strict fetal surveillance protocol

OBJECTIVE

To determine the perinatal outcome of monochorionic diamniotic (MCDA) twin pregnancies complicated by selective intrauterine growth restriction (sIUGR), which were classified according to the umbilical artery (UA) Doppler flow pattern of the IUGR twin.

METHODS

This was a retrospective cohort study of all MCDA twin pregnancies diagnosed with sIUGR and managed at a single tertiary referral center between 2012 and 2018. Cases were classified according to the UA Doppler flow pattern of the IUGR twin as Type I (positive end-diastolic flow), Type II (persistently absent/reversed end-diastolic flow) or Type III (intermittently absent/reversed end-diastolic flow). Patients with Type-II or -III sIUGR were hospitalized at 26-28 weeks of gestation for increased fetal surveillance. Perinatal and immediate and long-term neurodevelopmental outcomes were stratified according to the UA Doppler flow pattern at the final examination. Intact survival rate was defined as the number of infants surviving without neurological impairment, divided by the total number of fetuses. Composite adverse outcome, defined as any mortality, presence of severe brain lesions on postnatal transcranial ultrasound or severe neurological morbidity, was also assessed.

RESULTS

Of 88 MCDA twin pregnancies with sIUGR included in the study, 28 underwent selective termination by cord occlusion using radiofrequency ablation, resulting in a perinatal survival rate of 89.3% and a median gestational age (GA) at delivery of 33.8 (interquartile range (IQR), 28.8-38.2) weeks for the large cotwin. Expectant management was employed in 60 cases. In 26 (43.3%) cases in the expectant-management group, the classification according to the UA Doppler flow pattern changed during gestation, resulting in 26 (43.3%) cases of Type-I, 22 (36.7%) cases of Type-II and 12 (20.0%) cases of Type-III sIUGR at the final examination. The perinatal survival rate of both twins with sIUGR Types I, II and III at the final examination was 100%, 81.8% and 75.0%, respectively (P = 0.04). Two cases of double fetal death and one case of single fetal death occurred 1-4 weeks after the Doppler pattern had changed from Type I or Type II to Type III. The median GA at delivery was 34.8 (IQR, 33.1-35.7) weeks in Type I, 30.3 (IQR, 28.6-32.1) weeks in Type II and 32.0 (IQR, 31.3-32.6) weeks in Type III (P < 0.01). The total intact survival rate was 100% for Type I, 77.3% for Type II and 75.0% for Type III (P < 0.001). Multivariate analysis demonstrated that early GA at diagnosis (odds ratio (OR), 0.83 (95% CI, 0.69-0.99); P = 0.04) and the presence of Type II or III vs Type I at the last examination (OR, 13.16 (95% CI, 1.53-113.32); P = 0.02) were associated with preterm birth < 32 weeks' gestation. Early GA at diagnosis was also associated with the composite adverse outcome (OR, 0.60 (95% CI, 0.36-0.99); P = 0.04).

CONCLUSIONS

The classification system of MCDA pregnancy complicated by sIUGR, according to the UA Doppler flow pattern of the IUGR twin at final examination, is associated with perinatal outcome. Importantly, the UA Doppler flow pattern can change during gestation, which has an impact on the risk of fetal death. Nevertheless, under strict fetal surveillance, the perinatal outcome of these pregnancies is favorable. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Management of Twin Pregnancies: A Comparative Review of National and International Guidelines

Importance

Twin pregnancies are associated with a higher risk of perinatal mortality and morbidity compared with singleton and require more intensive prenatal care.

Objective

The aim of this study was to review and compare the recommendations from published guidelines on twin pregnancies.

Evidence Acquisition

A descriptive review of guidelines from the Royal College of Obstetricians and Gynaecologists, the International Society of Ultrasound in Obstetrics and Gynecology, the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, the National Institute for Health and Care Excellence, the Institute of Obstetricians and Gynaecologists of the Royal College of Physicians of Ireland, the International Federation of Gynecology and Obstetrics, the Society of Obstetricians and Gynaecologists of Canada, and the American College of Obstetricians and Gynecologists on the management of twin pregnancies was conducted.

Results

All the guidelines highlight the importance of an accurate assessment of chorionicity, amnionicity, and gestational age in the first trimester. They also recommend the performance of nuchal translucency and a detailed anomaly scan. The ultrasound surveillance protocol is similar in all guidelines, that is, every 2 weeks for monochorionic and every 4 weeks for dichorionic twins. On the other hand, there are differences regarding the timing and mode of delivery, especially in monochorionic diamniotic twins, in the definition and management of fetal growth discordance, the use of cervical length to screen for preterm birth, and the timing of corticosteroids' administration.

Conclusions

The differences in the reviewed guidelines on the management of twin pregnancies highlight the need for an adoption of an international consensus, in order to improve perinatal outcomes of twin 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.

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.

Current perspective and scope of fetal therapy: part 1

Fetal therapy term has been described for any therapeutic intervention either invasive or noninvasive for the purpose of correcting or treating any fetal malformation or condition. Fetal therapy is a rapidly evolving specialty and has gained pace in last two decades and now fetal intervention is being tried in many malformations with rate of success varying with the type of different fetal conditions. The advances in imaging techniques have allowed fetal medicine persons to make earlier and accurate diagnosis of numerous fetal anomalies. Still many fetal anomalies are managed postnatally because the fetal outcomes have not changed significantly with the use of fetal therapy and this approach avoids unnecessary maternal risk secondary to inutero intervention. The short-term maternal risk associated with fetal surgery includes preterm labor, premature rupture of membranes, uterine wall bleeding, chorioamniotic separation, placental abruption, chorioamnionitis, and anesthesia risk. Whereas, maternal long-term complications include risk of infertility, uterine rupture, and need for cesarean section in future pregnancies. The decision for invasive fetal therapy should be taken after discussion with parents about the various aspects like postnatal fetal outcome without fetal intervention, possible outcome if the fetal intervention is done, available postnatal intervention for the fetal condition, and possible short-term and long-term maternal complications. The center where fetal intervention is done should have facility of multi-disciplinary team to manage both maternal and fetal complications. The major issues in the development of fetal surgery include selection of patient for intervention, crafting effective fetal surgical skills, requirement of regular fetal and uterine monitoring, effective tocolysis, and minimizing fetal and maternal fetal risks. This review will cover the surgical or invasive aspect of fetal therapy with available evidence and will highlight the progress made in the management of fetal malformations in last two decades.

Management of monochorionic twins discordant for structural fetal anomalies

OBJECTIVE

To review the perinatal management and outcomes of monochorionic twin pregnancies (MC) discordant for congenital anomalies (DCA).

METHODS

Retrospective, study of all MC DCA cases referred to our tertiary referral center from 1997 to 2018. We excluded cases complicated with twin-to-twin transfusion syndrome, twin anemia-polycythemia sequence, twin reversed arterial perfusion sequence or selective intra-uterine growth restriction. Patients were counseled about the possibility of expectant (EM) or interventional management (selective feticide [SF] or termination of the entire pregnancy [TOP]).

RESULTS

One hundred eight of 4157 (2.6%) MC pregnancies were discordant for anomaly. Fifty two of 108 n(48.1%) underwent SF at a mean gestational age of 31.4 ± 5.9 weeks while 52/108(48.1%) opted for EM. Livebirth rate of the healthy co-twin was similar between the two groups (SF: 88.5% vs EM: 82.7%, P = .87). In the SF group, six healthy co-twins (6/52, 11.5%) died 5.3 ± 3.1 days after SF of the abnormal co-twin. In the EM group, in-utero demise of the abnormal twin occurred in 9 of 52 (17.3%) of the cases and was followed by the spontaneous demise of the healthy co-twin in 4 of 9 (44.4%) of these cases.

CONCLUSION

Selective feticide does not seem to significantly alter survival of the healthy co-twin compared to EM.

Foetal therapies and their influence on preterm birth

Foetal therapy aims to improve perinatal survival or to prevent severe long-term handicap. Foetal medicine opens a new territory by treating the foetus as a patient. The mother has nothing to gain in terms of health benefits, yet she is inherently also undergoing treatment. In utero foetal interventions can be divided into ultrasound-guided minimally invasive procedures, fetoscopic procedures and open hysterotomy procedures, which carry an inherent risk of ruptured membranes and preterm birth. In this review, we summarise the conditions that may benefit from foetal therapy and review the current therapies on offer, each with their associated risk of ruptured membrane and preterm birth. We also look into some risk limiting and preventative strategies to mitigate these complications.

Survival Outcomes by Fetal Weight Discordance after Laser Surgery for Twin-Twin Transfusion Syndrome Complicated by Donor Fetal Growth Restriction

INTRODUCTION

Management options for treatment of twin-twin transfusion syndrome (TTTS) with severe donor intrauterine growth restriction (IUGR) include fetoscopic laser surgery and umbilical cord occlusion (UCO). We studied perinatal survival outcomes in this select group after laser surgery, stratifying patients by preoperative estimated fetal weight (EFW) discordance.

METHODS

In this retrospective study of monochorionic diamniotic twin gestations with TTTS and selective donor IUGR who underwent laser surgery (2006-2017), preoperative EFW discordance was calculated ([(larger twin - smaller twin)/(larger twin)] × 100) and cases were divided into discordance strata. Severe EFW discordance was defined as >35%. The primary outcome was 30-day donor twin neonatal survival.

RESULTS

The 371 cases were distributed by discordance strata: ≤20% (74 [19.9%]), 21-25% (49 [13.2%]), 26-30% (68 [18.3%]), 31-35% (53 [14.3%]), 36-40% (51 [13.7%]), 41-45% (38 [10.2%]), >45% (38 [10.2%]). Donor 30-day survival declined as the discordance strata increased: 86.5, 85.7, 83.8, 75.5, 64.7, 63.2, and 65.8% (p = 0.0046); 30-day survival was inversely associated with severe discordance (>35%) (64.6 vs. 83.2%, p < 0.0001).

DISCUSSION

In TTTS cases complicated by donor IUGR with severe growth discordance, laser surgery was associated with donor survivorship greater than 60% suggesting that, in this setting, laser surgery remains a reasonable alternative treatment to UCO.

Impact of different prenatal management strategies in short- and long-term outcomes in monochorionic twin pregnancies with selective intrauterine growth restriction and abnormal flow velocity waveforms in the umbilical artery Doppler: a retrospective observational study of 108 cases

OBJECTIVES

To review perinatal and neurodevelopmental outcome (NDO) following selective fetoscopic laser coagulation (SFLC), cord coagulation (CC) or expectant management of monochorionic diamniotic twin pregnancies complicated with selective intrauterine growth restriction (sIUGR) and absent or reverse end-diastolic flow (AREDF) in the umbilical arteries (UA).

DESIGN AND SETTING

Single-centre retrospective observational study.

POPULATION

108 cases of sIUGR diagnosed before 26⁺⁶  weeks' gestation with AREDF in the UA.

METHODS

Survival rate and potential risk factors were analysed. NDO was assessed using parental questionnaires.

MAIN OUTCOMES MEASURES

Survival, gestational age at delivery and NDO.

RESULTS

SFLC, CC and EM were performed in 13, 50 and 45 cases, respectively, with an overall survival of 23.1, 40 and 77.8% and intrauterine demise of the co-twin of 30.8, 10 and 6.7% respectively. Intrauterine demise of the sIUGR twin occurred in 76.9 and 17.8% following SFLC and EM, respectively. The discordance in EFW at diagnosis was higher and absent/negative a-wave in the ductus venosus (DV) was more prevalent in the surgical groups. NDO in survivors at follow up was abnormal in 0 and 18% in the smaller twin following SFLC and EM, respectively, and in 25, 24 and 21% in the larger twin following SFLC, CC and EM, respectively.

CONCLUSION

SFLC yielded a poor result. EM seems a valid option when EFW discordance is <30% and a-wave in DV is positive. Otherwise, CC should be considered to protect the AGA co-twin. The long-term outcome of both small and large twins seems unaffected by the choice in primary prenatal management strategy.

TWEETABLE ABSTRACT

In type II sIUGR in MC twins, long-term neurodevelopment is normal in over 80% of the survivors.

Comparisons between two methods of multifetal pregnancy reduction in women with a dichorionic triamniotic triplet pregnancy

OBJECTIVE

To compare the different pregnancy outcomes of women with a reduced dichorionic triamniotic (DCTA) triplet managed with radiofrequency ablation (RFA) or potassium chloride (KCL).

MATERIALS AND METHODS

This was a retrospective cohort study. We studied 30 women of DCTA triplets managed with RFA as well as 85 managed with KCL. We compared the mean neonatal birthweight, median gestational age and perinatal mortality of two groups.

RESULTS

The mean neonatal birthweight of children in RFA group was 2572.4 g (SD, 407.0), vs 2899.3 g (SD, 554.9) in KCL group (P < 0.001). The rate of low birth weight infants was 23 (42.6%) vs. 16 (18.0%), respectively, (p < 0.005). However, there was no statistically significant difference in the median gestational age of delivery, premature birth before 32&37 weeks' gestation, neonatal brain injury or successful pregnancy between two groups. (We define the successful pregnancy as the condition that at least one child survives for a specific woman, while the failed one as no child survives.) CONCLUSION: What we took it for granted was that pregnancy outcomes in women with a reduced DCTA triplet managed with RFA was riskier than with KCL, however, we proved that it is not accurate. For women with a reduced DCTA triplet, managed with RFA is not much riskier than with KCL. What's more, most women have two children survived in RFA group, while in KCL group, only one child survives for most women. This result may change the management alternative for those women with DCTA triplet pregnancies who choose reduction, especially for women who desire to have two surviving and healthy fetuses.

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.

Fetal therapies as standard prenatal care in Japan

With recent advances in fetal medicine, various attempts have been made to save fetuses facing perinatal death or devastating consequences despite optimal management after birth. The concept of the fetus as a patient has been established through the application of in utero treatments. This paper reviews fetal therapies in order to highlight the role of perinatal medicine as standard prenatal care. Fetal therapies consist of medical therapy, percutaneous ultrasound-guided surgery, fetoscopic surgery, and open fetal surgery. In the 1980s, with advances in ultrasound imaging, percutaneous ultrasound-guided surgeries such as vesicoamniotic shunting for lower urinary tract obstruction and thoracoamniotic shunting (TAS) for fetal hydrothorax (FHT) were started. In the 1990s, fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS) was introduced, and later, a fetoscopic approach for congenital diaphragmatic hernia was also established. The revival of open fetal surgery, introduced in the 1980s by pediatric surgeons, began in the 2010s after a successful clinical study for myelomeningocele. Although many fetal therapies are still considered experimental, some have proven effective, such as FLS for TTTS, TAS for primary FHT, and radiofrequency ablation (RFA) for twin reversed arterial perfusion (TRAP) sequence. These three fetal therapies have been approved for coverage by Japan National Health Insurance as a result of clinical studies performed in Japan. FLS for TTTS, TAS for primary FHT, and RFA for TRAP sequence have become standard prenatal care approaches in Japan. These three minimally invasive fetal therapies will help improve the perinatal outcomes of fetuses with these disorders.

Perinatal outcomes of monochorionic diamniotic triplet pregnancies: a case series

Background

Triplet pregnancies are associated with higher fetal morbidity and mortality rates as well as life-threatening maternal complications. Monochorionic diamniotic (MCDA) triplet pregnancies are very rare compared to other types of triplet pregnancies.

Case presentation

We report three cases of MCDA triplet pregnancies between January 2012 and December 2017. Two of these MCDA triplet pregnancies received regular and intensive prenatal care, were diagnosed by ultrasonography during the first trimester or early second trimester, and had good perinatal outcomes. The case with irregular perinatal care had poor outcomes, and the MCDA triplet pregnancy was diagnosed intrapartum.

Conclusions

The possibility of continuing an MCDA triplet pregnancy should be recognized. Early diagnosis, regular antenatal care, close prenatal monitoring, and sufficient communication are recommended to obtain better perinatal outcomes in MCDA triplet pregnancies.

Outcome of Pregnancies Diagnosed with TRAP Sequence Prenatally: A Single-Centre Experience

INTRODUCTION

Twin reversed arterial perfusion (TRAP) sequence is a phenomenon seen in 1-3% of monochorionic twin pregnancies, where the acardiac fetus is found to have multiple anomalies. The normal pump twin maintains its own perfusion in addition to that of its acardiac co-twin. As a result, if the acardiac twin increases in size, the burden on the pump twin is increased, leading to cardiac failure, hydrops fetalis, polyhydramnios, premature delivery, and perinatal death. The outcome of pregnancy is largely dependent on the growth of the acardiac twin. In view of high perinatal loss, surgical techniques to interrupt the blood flow to the acardiac twin have been evaluated.

METHODS

We evaluated interstitial laser therapy, which is the main mode of therapy in our unit, of TRAP pregnancies referred over a 5-year period. Interstitial laser was offered if the blood flow in the acardiac twin was found to be persistent at 2 consecutive examinations or if there were cardiac or hydropic changes in the pump twin at the first examination.

RESULTS

A total of 18 cases of TRAP were referred during this period and all were counselled regarding fetal therapy if the situation were to deteriorate; 5 couples (27.7%) opted for termination of pregnancy; of the remaining 13, 7 (53.8%) agreed to perform intervention following confirmation of a normal karyotype. Six (85.7%) and 1 (14.3%) lasers were performed in the second and third trimesters, respectively; all 7 had a normal outcome of the pump twin. There were 6/13 (46.2%) in the expectant group who continued the pregnancy with no intervention, with 2 term live births (33.3%).

CONCLUSIONS

Our study confirms that there is a high risk of spontaneous loss in untreated pregnancies with TRAP, primarily due to polyhydramnios and fetal hydrops. In the pregnancies that underwent interstitial laser, there was a more favourable outcome. Interstitial laser is minimally invasive, safe, and feasible in experienced hands.

Complex multigestational anomalies

The increase in multiple gestation pregnancies has resulted in significant health care implications for both mother and child. Our ability to diagnose and intervene on an at-risk multi-gestation pregnancy has dramatically improved. It is important for the pediatric surgeon to be equipped with a basic fund of knowledge concerning these pregnancies. An understanding of amnionicity and chorionicity will equip the practitioner with the ability to identify which pregnancies are at risk for specific complications. This article highlights multi-gestation pregnancies that are monochorionic (single shared placenta) and can be complicated by twin-twin transfusion syndrome (TTTS), twin reversed arterial perfusion (TRAP) sequence, twin anemia polycythemia sequence (TAPS), or selective fetal intrauterine growth restriction (sIUGR). The risk of fetal demise is significant in these pregnancies. Understanding recommended surveillance and warning signs can alert surgeons to developing complications. Specialized fetal care centers possess the ability to intervene on these pregnancies in utero.

Maternal Complications and Hemodynamic Changes Following Intrauterine Interventions for Twin-to-Twin Transfusion Syndrome in Monochorionic Diamniotic Twin Pregnancies

Twin-to-twin transfusion syndrome (TTTS) is a challenging complication in monochorionic diamniotic (MCDA) twins. Intrauterine interventions, such as fetoscopic laser ablation and cord occlusion followed by amniodrainage, are established treatments. Little is known about maternal complications and hemodynamics following these interventions. We performed a retrospective analysis of maternal procedure-related complications and the impact of such procedures on maternal hemodynamics and blood characteristics. Within the study period, 100 women with severe TTTS treated by fetoscopic laser ablation (FLA) or cord occlusion (CO) were identified. Clinically relevant maternal complications were reported in four (4%) cases. There was a significant decrease in hemoglobin, hematocrit, and albumin between admission and postoperative measurements (all p < 0.001). Systolic and diastolic blood pressure, as well as maternal heart rate, decreased from time of skin suture to postoperative measurements (all p < 0.001). Within a 24 h interval, there was a positive correlation between hematocrit (Spearman's rho 0.325; p = 0.003), hemoglobin (Spearman's rho 0.379; p < 0.001), and albumin (Spearman's rho 0.360; p = 0.027), and the amount of amniodrainage during the intervention. Maternal procedure-related complications are relatively rare. Significant hemodynamic alterations and maternal hemodilution are common clinical findings following intrauterine interventions.

Maternal complications following open and fetoscopic fetal surgery: A systematic review and meta-analysis

OBJECTIVE

To establish maternal complication rates for fetoscopic or open fetal surgery.

METHODS

We conducted a systematic literature review for studies of fetoscopic or open fetal surgery performed since 1990, recording maternal complications during fetal surgery, the remainder of pregnancy, delivery, and after the index pregnancy.

RESULTS

One hundred sixty-six studies were included, reporting outcomes for open fetal (n = 1193 patients) and fetoscopic surgery (n = 9403 patients). No maternal deaths were reported. The risk of any maternal complication in the index pregnancy was 20.9% (95%CI, 15.22-27.13) for open fetal and 6.2% (95%CI, 4.93-7.49) for fetoscopic surgery. For severe maternal complications (grades III to V Clavien-Dindo classification of surgical complications), the risk was 4.5% (95% CI 3.24-5.98) for open fetal and 1.7% (95% CI, 1.19-2.20) for fetoscopic surgery. In subsequent pregnancies, open fetal surgery increased the risk of preterm birth but not uterine dehiscence or rupture. Nearly one quarter of reviewed studies (n = 175, 23.3%) was excluded for failing to report the presence or absence of maternal complications.

CONCLUSIONS

Maternal complications occur in 6.2% fetoscopic and 20.9% open fetal surgeries, with serious maternal complications in 1.7% fetoscopic and 4.5% open procedures. Reporting of maternal complications is variable. To properly quantify maternal risks, outcomes should be reported consistently across all fetal surgery studies.

Health-Related Quality of Life and Depression in Women following Intrauterine Interventions in Complicated Monochorionic Twin Pregnancies

INTRODUCTION

The aim of this study was to explore maternal health-related quality of life (HRQoL) and depression following intrauterine interventions in complicated monochorionic twin pregnancies at the Medical University Graz.

MATERIAL AND METHODS

In a cross-sectional questionnaire survey, women with at least one liveborn infant following intrauterine intervention during 2011 and 2015 were matched with uncomplicated monochorionic and dichorionic pregnancies. All completed the 12-Item Short Form Health Survey to measure HRQoL and the Patient Health Questionnaire-9 to measure depression. Results were compared with local normative values.

RESULTS

There were no differences in physical and mental HRQoL as compared to those with uncomplicated pregnancy. However, the whole study population had significantly lower HRQoL scores (p < 0.001) than the normative sample. Additionally, 11% of the whole study population experienced moderate (6.2%) or moderately severe (4.6%) depression. Women following uncomplicated dichorionic pregnancy revealed more depressive symptoms compared to women with intervention.

DISCUSSION

Women with at least one surviving infant following intervention in complicated monochorionic twin pregnancy do not seem to have an impaired HRQoL as compared to women following uncomplicated monochorionic or dichorionic pregnancies. However, twin pregnancy itself appears to impair HRQoL, at least in the first 4 postnatal years.

Discordance for placental mesenchymal dysplasia in a monochorionic diamniotic twin pregnancy: A case report

Placental mesenchymal dysplasia (PMD) occurs in about 1 in 5000 pregnancies. The differential diagnosis between PMD and partial mole is difficult on ultrasound scan, and karyotyping plays a key role in distinguishing PMD from partial mole. Our report is the first to report on the discordancy for PMD in a monochorionic setting.

Perinatal outcomes of single fetal survivor after fetal intervention for complicated monochorionic twins

OBJECTIVE

To compare perinatal outcomes between acute single fetal demise following fetoscopic laser photocoagulation to planned selective reduction (SR) in complicated monochorionic twin pregnancies.

METHODS

This was a secondary analysis of prospectively collected data in complicated monochorionic twin pregnancies from 2 fetal centers from 2011 to 2016. Group 1 included women undergoing fetoscopic laser photocoagulation for twin-twin transfusion syndrome (TTTS) who experienced a single fetal demise within 24 hours of the procedure. Group 2 consisted of women undergoing planned selective reduction (SR) with TTTS, and Group 3 SR for indications other than TTTS.

RESULTS

Survival of the remaining co-twin at birth was highest in Group 1 (n = 77 patients; 95%) compared with that in Group 2 (n = 15; 80%) and Group 3 (n = 32; 78%; P = .047). The preterm premature rupture of membrane rate was higher in Group 1 (47%) compared with that in Group 2 (33%) and Group 3 (7%; P < .001). Group 1 had a lower gestational age at delivery and shorter procedure-to-delivery interval compared with the other 2 groups (P < .01).

CONCLUSION

When single fetal demise occurs following fetoscopic laser photocoagulation, the surviving co-twin is more likely to survive to delivery but has higher PPROM rates and a shorter latency period compared with planned selective reduction for TTTS or other indications.

Selective intrauterine growth restriction in monochorionic diamniotic twin pregnancies

Selective intrauterine growth restriction (sIUGR) affects 10-15% of all monochorionic pregnancies. Early severe forms are associated with intrauterine demise or neurological adverse outcome for both twins. The characteristics of umbilical artery (UA) Doppler in the IUGR fetus determine three clinical types: (I) normal UA Doppler and associated with good prognosis; (II) persistently absent/reverse UA end-diastolic flow and associated with early deterioration of the IUGR twin and very preterm delivery; (III) intermittently absent/reverse end-diastolic flow in the UA, and associated with unexpected fetal demise or neurological injury in one or both twins. Types II and III pose important challenges for management. Placental laser or cord occlusions do not seem to increase survival, but they might improve the outcomes of the larger twin. The use of an algorithm with severity criteria may help in counseling and planning management.

Uncommon complications of monochorionic twin pregnancies: Twin reversed arterial perfusion sequence

Introduction

Twin reversed arterial perfusion (TRAP) sequence occurs when there is one non-viable twin without cardiac structures and a viable pump twin that perfuses the acardiac mass. This study aims to investigate the management and immediate neonatal outcomes for monochorionic multiple pregnancies complicated by TRAP referred to the NSW Fetal Therapy Centre (NSW FTC).

Methods

Retrospective cohort study of multiple pregnancies referred to NSW FTC between April 2006 and April 2014, reviewing data for cases of TRAP sequence (n = 19, including two triplet cases) compared to a timeframe matched sample of uncomplicated monochorionic diamniotic (MCDA) twin pregnancies managed in the unit (n = 45).

Results

Primary management of the 19 TRAP cases was expectant management in 10 (53%), radiofrequency ablation (RFA) in 6 (32%), and bipolar cord coagulation, amniodrainage and termination of pregnancy in 1 case each. 1 of 6 RFA cases had pump twin demise <1 week post-procedure. Average gestation at birth (35.1 ± 5.0 vs. 35.0 ± 2.8 weeks) and mean birthweight (2157 ± 1019 g vs. 2245 ± 537 g) were similar between TRAP pump fetuses and uncomplicated MCDA cases. Pump twin survival was 81% (twins only) compared to 98% for uncomplicated MCDA twins (P = 0.02), and in 5 of 19 (26%) TRAP pregnancies the pump fetus had a congenital anomaly.

Conclusion

Mean gestational age at birth and mean birthweight were similar for both TRAP and uncomplicated MCDA pregnancies. TRAP cases, however, had higher perinatal mortality, and high rates of congenital anomaly. The overall neonatal outcome at NSW FTC for TRAP cases is similar to reported international outcomes.

Clinical Outcomes after Selective Fetal Reduction of Complicated Monochorionic Twins with Radiofrequency Ablation and Bipolar Cord Coagulation

AIMS

To review pregnancy outcomes, complication rates and neonatal neural development of selective termination procedures for complicated monochorionic (MC) twins.

METHODS

This was a retrospective review of the pregnancies that underwent selective reduction with radiofrequency ablation (RFA) and bipolar cord coagulation (BCC) in our institution.

RESULTS

Forty-eight cases underwent selective reduction with BCC and the remaining 45 with RFA. Overall survival was not statistically different between the RFA and BCC groups (71.1 and 62.5%, p = 0.379). With regard to the indications, the survival rates were not significantly different for twin to twin transfusion syndrome, twin reversed arterial perfusion, discordant anomalies and selective intrauterine growth restriction. Preterm premature rupture of membrane was not statistically different between the BCC and RFA groups (47.9 and 33.3%, p = 0.153). Five foetuses presented with abnormal middle cerebral artery-peak systolic velocity in the BCC group and 4 in the RFA group (p = 0.829). In the BCC group, neurological injury was detected in 2 neonates, presenting with cerebral dysplasia on MR scanning. In the RFA group, intracranial haemorrhage Grade III was detected in one neonate with cranial ultrasound (p = 0.607).

CONCLUSIONS

Overall survival and complication rates following selective reduction in complicated MC twin pregnancies is similar irrespective of whether the reduction was performed using RFA or BCC. Key Message: It seems that selective reduction in MC pregnancies with RFA does not carry a significant decrease in the overall survival and complication rates than the cases with BCC. According to our data, neurodevelopmental impairment of the co-twins is relatively seldom after selective reduction.

Forty cases of twin reversed arterial perfusion sequence treated with radio frequency ablation using the multistep coagulation method: a single-center experience

OBJECTIVE

To report the pregnancy outcomes of patients with twin reversed arterial perfusion (TRAP) sequence treated by radiofrequency ablation (RFA).

METHODS

This was a retrospective study of TRAP sequences treated in a single center between March 2002 and February 2015. Forty patients underwent RFA with expandable tines through a multistep coagulation method between 15 and 26 gestational weeks. The primary outcome was neonatal survival to discharge.

RESULTS

The overall survival of the pump twin was 85%. The survival rates in monochorionic-monoamniotic (MCMA) pregnancies and monochorionic-diamniotic pregnancies were 66.7% (4/6) and 87.9% (29/33), respectively. One triplet was treated successfully and delivered at 36 weeks of gestation. One of 35 live births (2.9%) had preterm premature rupture of membranes less than 34 weeks, resulting in infant death. In five intrauterine pump twin deaths, two cases were MCMA twins with cord entanglement, and three cases were MCDA twins with acardius anceps.

CONCLUSIONS

Our study supports the effectiveness of RFA for TRAP sequence after 15 weeks of gestation. The presence of MCMA twins or acardius anceps is associated with a high risk of pump twin death after RFA. © 2016 John Wiley & Sons, Ltd.

Chorioamniotic membrane separation after fetoscopy in monochorionic twin pregnancy: incidence and impact on perinatal outcome

OBJECTIVE

To evaluate the incidence of chorioamniotic membrane separation (CMS) after fetoscopy in monochorionic diamniotic (MCDA) twins and its impact on pregnancy outcome.

METHODS

The study group comprised a consecutive series of 338 women with an MCDA pregnancy complicated by twin-twin transfusion syndrome (TTTS) or selective intrauterine growth restriction (sIUGR) treated with selective laser photocoagulation of communicating vessels (SLPCV) or cord occlusion (CO). Data obtained included cervical length, gestational age at procedure, type and duration of surgery and placental location. The incidence of CMS, the rates of miscarriage and preterm prelabor rupture of membranes (PPROM), gestational age at delivery and neonatal survival were recorded.

RESULTS

Of the study population of MCDA pregnancies, 270 (79.9%) had TTTS and 68 (20.1%) had sIUGR. SLPCV was performed in 252 (74.6%) cases and CO in 86 (25.4%). Postoperative CMS was observed in 70 (20.7%) cases. Patients with CMS had higher rates of miscarriage (14.3% vs 7.1%; P = 0.049), PPROM before 32 weeks (43.3% vs 13.7%; P < 0.001) and preterm delivery before 32 weeks (53.3% vs 26.1%; P < 0.001) and a lower rate of neonatal survival of at least one twin (81.7% vs 93.6%; P = 0.003). Multivariate analysis showed that gestational age at surgery was the only independent predictor, with the highest proportion of CMS occurring in cases that underwent surgery before 18 weeks' gestation (odds ratio, 2.941 (95% CI, 1.640-5.275); P < 0.001). There was no influence of cervical length, placental location, duration of surgery or type of surgery on the risk of CMS.

CONCLUSIONS

CMS complicated one-fifth of all MCDA pregnancies that underwent fetoscopy. It appeared to be more common in those who underwent surgery before 18 weeks' gestation and was associated with poorer outcomes. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.