Twin-Twin Transfusion Syndrome with and without Selective Fetal Growth Restriction Prior to Fetoscopic Laser Surgery: Short and Long-Term Outcome

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.

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

BACKGROUND

Research in singletons identified fetal growth restriction (FGR) as a risk factor for retinopathy of prematurity (ROP), but is generally subject to confounding by genetic, obstetric, and maternal factors. We investigated the effect of FGR on ROP in growth-discordant identical twins, thereby controlling for confounding factors.

METHODS

All data of monochorionic (MC) twin pairs with a birth weight discordance ≥20% born in our center between 2010 and 2021 were retrospectively reviewed for the presence of ROP. Potential risk factors for ROP were analyzed. Outcomes were compared between the smaller and larger twin.

RESULTS

We included 88 MC twin pairs with growth discordance. In 34% (30/88), both neonates were at risk of ROP. Prevalence of ROP was higher among the smaller twin compared to the larger twin, 30% (9/30) versus 13% (4/30), respectively (OR 2.8, 95% CI: 1.2-6.6). The smaller twin had a longer duration of mechanical ventilation (8 (1-20) versus 2 (1-4) days) and received their first red blood cell transfusion at an earlier postmenstrual age (29.6 (28.1-31.6) versus 30.4 (29.7-32.6) weeks).

CONCLUSIONS

In this identical twin model, FGR is associated with almost tripled odds of ROP development, suggesting that both unfavorable antenatal growth conditions and adverse neonatal outcomes affect postnatal retinal vascular proliferation.

IMPACT

Fetal growth restriction in growth-discordant identical twins is associated with almost tripled odds of developing retinopathy of prematurity in the smaller twin. Since these twins do not only differ in birth weight but also duration of mechanical ventilation and timing of the first red blood cell transfusion, both unfavorable antenatal growth conditions and adverse neonatal outcomes can affect postnatal retinal vascular proliferation. More attention for preventing retinopathy of prematurity is needed in those with fetal growth restriction who received prolonged duration of mechanical ventilation, oxygen supplementation, or a first red blood cell transfusion <32 weeks postmenstrual age.

Fetal growth changes and prediction of selective fetal growth restriction following fetoscopic laser coagulation in twin-to-twin transfusion syndrome

OBJECTIVE

To investigate fetal growth changes and predictive factors for selective fetal growth restriction (sFGR) in patients with twin-to-twin transfusion syndrome (TTTS) after fetoscopic laser coagulation (FLC).

METHODS

This retrospective study included twin-pregnant women with fetal TTTS who underwent FLC at our institution between 2011 and 2020. Twin pairs who survived at least 28 days after FLC and at least 28 days after birth were included. A paired t-test was used to compare the mean discordance between the estimated fetal weights at the FLC and the birth weights. The predictive factors for sFGR after FLC were evaluated using univariate and multivariate logistic regression analyses.

RESULTS

A total of 119 eligible pairs of patients who underwent FLC were analyzed. The weight percentile at birth significantly decreased after FLC in the recipients (53.7±30.4 percentile vs. 43.7±28.0 percentile; P<0.001), but increased in the donors (11.5±17.1 percentile vs. 20.7±22.8 percentile; P<0.001). Additionally, the mean weight discordance of twin pairs significantly decreased after FLC (23.9%±12.7% vs. 17.3%±15.7%; P<0.001). After FLC, Quintero stage ≥3, pre-FLC sFGR, abnormal cord insertion, and post-FLC abnormal umbilical artery Doppler (UAD) were all significantly higher in the sFGR group than the non-sFGR group. The prediction model using these variables indicated that the area under the receiver operating characteristic curve was 0.898.

CONCLUSION

The recipient weight percentile decreased, whereas donor growth increased, resulting in reduced weight discordance after FLC. The Quintero stage, pre-FLC sFGR, and post-FLC abnormal UAD were useful predictors of sFGR after FLC in TTTS.

Outcome following laser surgery of twin-twin transfusion syndrome complicated by selective fetal growth restriction: systematic review and meta-analysis

OBJECTIVE

The published literature reports mostly on the outcome of twin pregnancies complicated by twin-twin transfusion syndrome (TTTS) without considering whether the pregnancy is also complicated by another pathology, such as selective fetal growth restriction (sFGR). The aim of this systematic review was to report on the outcome of monochorionic diamniotic (MCDA) twin pregnancies undergoing laser surgery for TTTS that were complicated by sFGR and those not complicated by sFGR.

METHODS

MEDLINE, EMBASE and Cochrane databases were searched. The inclusion criteria were studies reporting on MCDA twin pregnancies with TTTS undergoing laser therapy that were complicated by sFGR and those not complicated by sFGR. The primary outcome was the overall fetal loss following laser surgery, defined as miscarriage and intrauterine death. The secondary outcomes included fetal loss within 24 h after laser surgery, survival at birth, preterm birth (PTB) prior to 32 weeks of gestation, PTB prior to 28 weeks, composite neonatal morbidity, neurological and respiratory morbidity, and survival free from neurological impairment. All outcomes were explored in the overall population of twin pregnancies complicated by sFGR vs those not complicated by sFGR in the setting of TTTS and in the donor and recipient twins separately. Random-effects meta-analysis was used to combine data and the results are reported as pooled odds ratios (OR) with 95% CI.

RESULTS

Five studies (1710 MCDA twin pregnancies) were included in the qualitative synthesis and four in the meta-analysis. The overall risk of fetal loss after laser surgery was significantly higher in MCDA twin pregnancies with TTTS complicated by sFGR (20.90% vs 14.42%), with a pooled OR of 1.6 (95% CI, 1.3-1.9) (P < 0.001). The risk of fetal loss was significantly higher in MCDA twin pregnancies with TTTS and sFGR for the donor but not for the recipient twin. The rate of live twins was 79.1% (95% CI, 72.6-84.9%) in TTTS pregnancies with sFGR and 85.6% (95% CI, 81.0-89.6%) in those without sFGR (pooled OR, 0.6 (95% CI, 0.5-0.8)) (P < 0.001). There was no significant difference in the risk of PTB prior to 32 weeks of gestation (P = 0.308) or prior to 28 weeks (P = 0.310). Assessment of short- and long-term morbidity was affected by the small number of cases. There was no significant difference in the risk of composite (P = 0.506) or respiratory (P = 0.531) morbidity between twins complicated by TTTS with vs those without sFGR, while the risk of neurological morbidity was significantly higher in those with TTTS and sFGR (pooled OR, 1.8 (95% CI, 1.1-2.9)) (P = 0.034). The risk of neurological morbidity was significantly higher for the donor twin (pooled OR, 2.4 (95% CI, 1.1-5.2)) (P = 0.029) but not for the recipient twin (P = 0.361). Survival free from neurological impairment was observed in 70.8% (95% CI, 45.0-91.0%) of twin pregnancies with TTTS complicated by sFGR and in 75.8% (95% CI, 51.9-93.3%) of those not complicated by sFGR, with no difference between the two groups.

CONCLUSIONS

sFGR in MCDA pregnancies with TTTS represents an additional risk factor for fetal loss following laser surgery. The findings of this meta-analysis may be useful for individualized risk assessment of twin pregnancy complicated by TTTS and tailored counseling of the parents prior to laser surgery. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Subclassification of fetal growth restriction type IIa vs type IIb applied to twin-twin transfusion syndrome

BACKGROUND

Subclassification of monochorionic twins with selective fetal growth restriction type II into IIa vs IIb has been proposed because of differing neonatal survival outcomes of the fetus with growth restriction after laser surgery based on preoperative Doppler findings in the middle cerebral artery and ductus venosus. There is substantial clinical overlap between selective fetal growth restriction and twin-twin transfusion syndrome.

OBJECTIVE

This study aimed to compare donor twin neonatal survival after laser surgery in cases of twin-twin transfusion syndrome with concomitant donor fetal growth restriction type IIa vs IIb.

STUDY DESIGN

This was a retrospective study of monochorionic multifetal pregnancies treated with laser surgery for stage III twin-twin transfusion syndrome and concomitant donor twin fetal growth restriction type II at a referral center from 2006 to 2021. Donor fetal growth restriction type II was defined as having an estimated fetal weight <10th percentile with persistent absent and/or reversed end-diastolic velocity in the umbilical artery. Moreover, patients were subclassified as type IIa (having normal middle cerebral artery peak systolic velocities and ductus venosus Doppler waveforms) vs type IIb (having middle cerebral artery peak systolic velocities ≥1.5 multiples of the median and/or ductus venosus with persistent absent or reversed atrial systolic flow). This study compared 30-day neonatal survival of the donor twin by fetal growth restriction type IIa vs IIb using logistic regression to adjust for relevant preoperative covariates (P<.10 in bivariate analysis).

RESULTS

Of 919 patients who underwent laser surgery for twin-twin transfusion syndrome, 262 had sstage III donor or donor and recipient twin-twin transfusion syndrome; of these patients, 189 (20.6%) had concomitant donor fetal growth restriction type II. Moreover, 12 patients met the exclusion criteria, yielding 177 patients (19.3%) who composed the study cohort. Patients were subclassified as donor fetal growth restriction type IIa (146 [82%]) vs type IIb (31 [18%]). Donor neonatal survival for fetal growth restriction type IIa vs IIb was 71.2% vs 41.9% (P=.003). Recipient neonatal survival did not differ between the 2 types (P=1.000). Patients classified with twin-twin transfusion syndrome and concomitant donor fetal growth restriction type IIb were 66% less likely to have neonatal survival of the donor after laser surgery (adjusted odds ratio, 0.34; 95% confidence interval, 0.15-0.80; P=.0127). The logistic regression model was adjusted for gestational age at the procedure, estimated fetal weight percent discordance, and nulliparity. The c-statistic was 0.702.

CONCLUSION

For patients with stage III twin-twin transfusion syndrome and concurrent donor fetal growth restriction with persistent absent or reversed end-diastolic velocity in the umbilical artery (ie, fetal growth restriction type II), subclassification into fetal growth restriction type IIb based on elevated middle cerebral artery peak systolic velocity and/or abnormal ductus venosus flow in the donor conveyed poorer prognosis. Although donor neonatal survival after laser surgery was lower for patients with stage III twin-twin transfusion syndrome with donor fetal growth restriction type IIb than patients with stage III twin-twin transfusion syndrome with donor fetal growth restriction with type IIa, laser surgery for fetal growth restriction type IIb in the setting of twin-twin transfusion syndrome (as opposed to pure selective fetal growth restriction type IIb) still allows for the possibility of dual survivorship and should be offered with shared decision-making when counseling patients on management options.

Increased Risk of Retinopathy of Prematurity in Donors with Twin-to-Twin Transfusion Syndrome: A Cohort Study

INTRODUCTION

The purpose of this study was to evaluate the within-pair difference in retinopathy of prematurity (ROP) between donors and recipients with twin-to-twin transfusion syndrome (TTTS) and to identify risk factors for ROP development.

METHODS

This retrospective cohort study included 147 TTTS twin pairs managed between 2002 and 2022 and eligible for ROP screening. Primary outcomes were any stage ROP and severe ROP. Secondary outcomes were hemoglobin at birth, red blood cell transfusions, mechanical ventilation days, postnatal steroids, and neonatal morbidity. Donor status was defined as having polyhydramnios pre-laser.

RESULTS

Rates of any stage ROP (23% vs. 14%) and severe ROP (8% vs. 3%) were significantly higher in donors compared to recipients. Donors received a higher number of blood transfusions (1 [±1.9] versus 0.7 [±1.5]). Five factors were univariately associated with any stage ROP: donor status (odds ratio [OR] 1.9; 95% CI 1.3-2.9), lower gestational age (GA) at birth (OR 1.7; 95% CI 1.4-2.1), small for GA (OR 2.1; 95% CI 1.3-3.5), mechanical ventilation days (OR 1.1; 95% CI 1.1-1.2), and blood transfusions in phase 1 (OR 2.3; 95% CI 1.2-4.3). Three factors were independently associated with any stage ROP: donor status (OR 1.8; 95% CI 1.1-2.9), lower GA at birth (OR 1.6; 95% CI 1.2-2.1), and mechanical ventilation days (OR 1.1, 95% CI 1.0-1.1). Donor status was univariately associated with severe ROP (OR 2.3, 95% CI 1.1-5.0).

CONCLUSION

Any stage ROP and severe ROP are detected twice as frequently in donors compared to recipients. Increased awareness for ROP is needed in donors, especially those with lower GA at birth and longer duration of mechanical ventilation.

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.

Perinatal and Long-Term Outcome of Endoscopic Laser Surgery for Twin-Twin Transfusion Syndrome with and without Selective Fetal Growth Restriction: A retrospective cohort study

OBJECTIVE

Report survival rates, neonatal mortality and morbidity and long-term outcomes of monochorionic(MC) twin pregnancies complicated by twin-to-twin transfusion syndrome(TTTS)or TTTS plus selective fetal growth restriction(sFGR)treated by endoscopic laser surgery.

METHODS

Retrospective cohort study including 149 MC twin pregnancies complicated by TTTS or TTTS plus sFGR.Medical records were reviewed for survival rates,neonatal mortality, neonatal morbidity and long-term outcomes at 2 and 6 years of age.

RESULTS

Survival of both babies was higher in the TTTS group than in the TTTS plus sFGR group(72.9%vs.54.8%);survival of at least one baby was similar in the two groups (90.7% and 88.1%).The incidence of severe neurological disability was not significantly different between TTTS and TTTS plus FGR group at both stages,1.9% vs 2.3% (p-value = 1) and 3.4%vs6.1%(p-value=0.31).Multivariable analysis demonstrated that intact neurological outcome at 2 years of age was related with gestational age at birth and z score birthweight, and at 6 years of age with gestational age at birth,z score birthweight and TTTS stage4.sFGR or abnormal brain findings at neonatal ultrasound were not related with impaired neurological outcome at 2 or 6 years of age.

CONCLUSIONS

In pregnancies with TTTS and TTTS plus sFGR survival of at least one baby and long-term neurological outcome are comparable between both groups. This article is protected by copyright. All rights reserved.

Early- and late-onset selective fetal growth restriction in monochorionic twin pregnancy with expectant management

OBJECTIVE

This study aimed to identify selective fetal growth restriction (sFGR) in monochorionic twin (MCT) pregnancy with expectant management.

METHODS

We retrospectively analyzed cases of sFGR between January 2015 and December 2019 in Peking University Third Hospital. We included sFGR according to the International Society of Ultrasound in Obstetrics and Gynecology diagnostic criteria. We excluded those cases where a significant fetal structural abnormality, twin reversed arterial perfusion (TRAP), genetic syndrome or aneuploidy; cases terminated for maternal complications or for personal reasons; pregnancies that had a fetal intervention, such as fetoscopic laser photocoagulation (FLP) for vascular anastomoses, fetal reduction by radiofrequency ablation (RFA) and microwave ablation (MVA). We didn't excluded those cases that had amnioreduction therapy. According to the gestational age at onset (before 24 weeks or after), data were analyzed to identify the risk factors associated with fetal prognostic outcomes. Primary outcomes included survival of at least one twin and both twins. Secondary outcomes included gestational age of delivery, live birth weight, Apgar <7 in 5 min, admission to the neonatal unit and neonatal death. Kruskal-Wallis rank tests were used to compare non-normally distributed data, whereas categorical data were matched using Fisher's exact test or χ² tests. ANOVA was used to compare normally distributed data, followed by a post-hoc Bonferroni analysis. Multivariate binary logistic regression was used to identify the factors connected with intrauterine death.

RESULTS

There were 119 pregnancies that qualified for investigation, 75 (63.0%) were categorized as early-onset sFGR and 44 (37.0%) as late-onset sFGR. The rate of survival of at least one twin (82.7% vs. 95.5%), survival of both twins (73.3% vs. 88.6%) were all reduced in the early-onset sFGR group, compared to the late-onset sFGR group. Babies born alive of fetal growth restriction (FGR) and appropriate growth for gestational age (AGA) fetuses showed similar results in the two groups regarding birth weight, 5-min Apgar score <7, neonatal death, and 28-day survival rate. A multivariable model was used to predict the intrauterine death of at least one twin. The odds ratio were significantly higher for superimposed twin-twin transfusion syndrome (TTTS) (OR 17.915, 95%CI 3.699∼86.756) and Types Ⅱ/Ⅲ sFGR (OR 4.619, 95%CI 1.074∼19.869).

CONCLUSIONS

In MCT pregnancies, early-onset sFGR had a poorer survival of at least one or both twins, but there was no statistical difference in the prognosis after live birth, neither for FGR babies nor those of AGA. Superimposed TTTS and Types Ⅱ/Ⅲ sFGR had a worse perinatal outcome. This information could be provided to the parents during prenatal counselling.

Prediction of post-laser fetal death in selective growth restriction complicating twin-twin transfusion syndrome using standardized definitions

OBJECTIVE

Selective fetal growth restriction (sFGR) complicating twin-twin transfusion syndrome (TTTS) is associated with a 3-6-fold increased risk of fetal demise after fetoscopic laser surgery (FLS). Identifying these patients is challenging due to varying definitions of sFGR used in the literature. The objective of this study was to determine the association of three currently used definitions for sFGR with demise of the smaller twin, typically the donor, following FLS for TTTS.

METHODS

This was a retrospective cohort study of monochorionic diamniotic twin pregnancies undergoing FLS for TTTS between January 2015 and December 2018. Classification of the cohort as sFGR or non-sFGR was performed using three different definitions: (1) estimated fetal weight (EFW) of one twin < 10^th centile and intertwin EFW discordance > 25%, according to the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) (Definition A); (2) EFW of one twin < 3^rd centile, according to the solitary criterion for sFGR reported in a Delphi consensus (Definition B); and (3) presence of at least two of four of the following criteria: EFW of one twin < 10^th centile, abdominal circumference of one twin < 10^th centile, intertwin EFW discordance of ≥ 25% and umbilical artery pulsatility index of the smaller twin > 95^th centile, according to the contributory criteria for sFGR in monochorionic diamniotic twin pregnancies reported in the Delphi consensus (Definition C). Pearson's χ² and univariate and multivariate logistic regression analyses were performed to assess the association of classification as sFGR according to the different definitions with fetal demise within 48 h after FLS.

RESULTS

A total of 124 pregnancies underwent FLS for TTTS during the study period. Of these, 46/124 (37.1%) were identified as having sFGR according to the ISUOG criteria (Definition A), 57/124 (46.0%) based on EFW < 3^rd centile (Definition B) and 70/124 (56.5%) according to the Delphi contributory criteria (Definition C). There were no differences in maternal body mass index, recipient twin amniotic fluid volume, gestational age (GA) at intervention or GA at delivery between sFGR and non-sFGR cases for any of the three definitions. There were also no differences in the rates of postprocedure recipient demise or Doppler abnormalities in the recipient. Regardless of the definition used, sFGR cases showed a significantly higher rate of postprocedure donor twin demise compared with that in non-sFGR cases (Definition A: 28.3% vs 3.8%, P < 0.01; Definition B: 22.8% vs 4.5%, P = 0.02; Definition C: 22.9% vs 0%, P < 0.01). For all of the sFGR definitions, the rate of Stage-III TTTS was increased in sFGR compared to non-sFGR cases (Definition A: 65.2% vs 35.9%, P ≤ 0.01; Definition B: 59.6% vs 35.8%, P = 0.04; Definition C: 62.9% vs 25.9%, P < 0.01). All cases of donor demise met the criteria for sFGR according to Definition C. Classification as sFGR according to Definition C was associated with a significantly higher rate of post-FLS donor demise compared to Definitions A and B (χ² , 15.32; P < 0.01). Logistic regression analysis demonstrated that sFGR cases had an increased risk of donor demise (Definition A: odds ratio (OR), 4.97 (95% CI, 1.77-13.94), P < 0.01; Definition B: OR, 4.39 (95% CI, 1.36-14.15), P = 0.01) and that staging of TTTS was also predictive of demise (OR, 2.26 (95% CI, 1.14-4.47), P = 0.02). After adjusting for GA at intervention and stage of TTTS, the results were similar (Definition A: OR, 6.48 (95% CI, 2.11-24.56), P = 0.002; Definition B: OR, 4.16 (95% CI, 1.35-15.74), P = 0.02).

CONCLUSIONS

The rate of fetal demise following FLS for TTTS is increased in the presence of sFGR. Improving diagnosis of sFGR should improve counseling and may affect management. The Delphi method of defining sFGR based on the presence of at least two of four contributory criteria had the highest predictive value for donor demise following FLS for TTTS. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Twin twin transfusion syndrome with and without selective fetal growth restriction: Predictors of donor demise

OBJECTIVE

Evaluate survival in twin twin transfusion syndrome (TTTS) with and without selective fetal growth restriction (sFGR) after fetoscopic laser surgery (FLS).

METHODS

Retrospective study of monochorionic diamniotic twins undergoing FLS. The cohort was classified as TTTS and TTTS with sFGR. Baseline, intra-operative and postoperative variables were analyzed. Mann-Whitney U, Pearson chi-square, Fisher's exact, t-test and receiver operating characteristic (ROC) curve analysis were performed.

RESULTS

Four hundred and ninety-two pregnancies were included, 304 (61.78%) TTTS and 188 (38.22%) TTTS with sFGR. No difference in donor outcomes. TTTS group had higher donor estimated fetal weight (EFW%) percentile (19.7 ± 18.8 vs. 2.2 ± 2.1, p < 0.001). Significant predictors for demise at 30 days were 37% intertwin weight discordance (IWD) with donor EFW% < first (area under ROC curve [AUC] = 0.85, p = 0.001) or IWD >25% and intertwin umbilical artery pulsatility index discordance (DUAPI) ≥0.4 (AUC = 0.71, p = 0.001).

CONCLUSION

Combination of IWD of 37% and donor EFW% <first was most predictive for demise 30 days after birth. DUAPI ≥0.4 was also associated with increased risk for demise.

Perinatal outcomes and factors affecting the survival rate of fetuses with twin-to-twin transfusion syndrome treated with fetoscopic laser coagulation: a single-center seven-year experience

OBJECTIVES

This single-center study aimed to assess the perinatal outcomes and its associated factors in fetuses with twin-to-twin transfusion syndrome (TTTS) treated by fetoscopic laser coagulation (FLC).

METHODS

In this retrospective study, we included fetuses prenatally diagnosed with TTTS at Asan Medical Center, Seoul, Korea, between October 2011 and December 2018. All patients with TTTS stage II or higher and those with stage I TTTS coupled with symptomatic polyhydramnios or cardiac dysfunction were eligible for FLC.

RESULTS

A total of 172 cases of monochorionic diamniotic twins and one case of dichorionic triamniotic triplets were prenatally diagnosed with TTTS and treated with FLC. The median gestational ages (GAs) at diagnosis and FLC were 20.3 and 20.5 weeks, respectively. The median GA of survivors at delivery was 32.5 weeks. The overall at least one twin- and double-survival rates within 28 days after birth were 82.1% and 55.5%, respectively. The GAs at diagnosis and FLC, Quintero stage, inter-twin weight discordance, associated selective intrauterine growth restriction (sIUGR), procedure time, volume of amnioreduction, preterm prelabor rupture of membranes (PPROM) within one week after FLC, intraoperative intrauterine bleeding, and chorioamnionitis were significant predictive factors of perinatal death. Associated sIUGR, absent end-diastolic flow of umbilical artery, and abnormal cord insertion were significantly associated with donor demise in utero, whereas lower GA at diagnosis and FLC, smaller twins at FLC, pulsatile umbilical vein, and presence of mitral regurgitation were significantly associated with recipient demise in utero. Since the application of the Solomon technique, the survival rate has improved from 75.4% to 88.8%. The FLC before 17 weeks was associated with PPROM within one week after FLC and lower survival rate, whereas that after 24 weeks was associated with twin anemia-polycythemia sequence and higher survival rate. We reached a survival rate of 82% for at least one survival with only 12 procedures.

CONCLUSIONS

FLC is an effective treatment for TTTS. The learning curve reached the acceptable target faster than in previous studies. Several prenatal parameters are identified as predictive factors of fetal survival in TTTS treated with FLC.

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.