Fetoscopic surgery in triplet pregnancies: a multicenter case series

A systematic review of early intrauterine intervention at 12 + 0 to 16 + 6 weeks in twin reversed arterial perfusion sequence

There is some evidence that in twin reversed arterial perfusion sequence, intervention at early gestational age could prevent a spontaneous death of the pump twin, achieving a better global survival.

OBJECTIVE

To review the perinatal outcomes of early intervention in pregnancies complicated by twin reversed arterial perfusion (TRAP) sequence.

STUDY DESIGN

A comprehensive search from inception to December 2022 was conducted on databases including MEDLINE, EMBASE, Cochrane Library and LILACS. All studies that reported intervention in twin or triplet pregnancy complicated with TRAP sequence at 12 + 0 to 16 + 6 weeks of gestation were eligible. A descriptive and bivariate analysis was performed.

RESULTS

Out of the 222 full-text articles, 44 studies reporting 108 cases of early intervention in TRAP sequence were included. A successful procedure was achieved in 105 (95.5 %) interventions: 89 (94.7 %) among twin pregnancies and 16(100 %) among triplet pregnancies. An overall livebirth rate was achieved in 75 patients (70.8 %): intrafetal laser group 55 (73.3 %), radiofrequency 10 (76.9 %) and endoscopic laser 3 (75.0 %). The median gestational age at delivery was 38 + 0 (37 + 4 - 39 + 4) weeks. The median treatment-delivery interval was 23 + 2 (IQR, 21 + 0-25 + 6) weeks. The most frequent adverse outcomes reported were preterm labor in 7 (13.7 %) patients. There were no severe adverse maternal outcomes.

CONCLUSION

Early intervention with intrafetal laser and radiofrequency in TRAP sequence achieves a livebirth rate of the pump twin of about 75 %.

Feasibility of fetoscopic laser coagulation in triplet pregnancy

OBJECTIVE

To report the experiences of triplet pregnancies complicated by twin-to-twin transfusion syndrome (TTTS) treated with fetoscopic laser coagulation at a single center.

METHODS

Herein, we conducted a retrospective analysis to investigate the management and perinatal outcomes of triplet pregnancies with TTTS treated at a single institution between 2017 and 2022.

RESULTS

Seven of the 98 triplet pregnancies (7.1%) encountered were complicated by TTTS, and all were dichorionic triamniotic triplets. Of the seven triplet pregnancies complicated by TTTS, four were treated with fetoscopic laser coagulation at our center, at a median gestational age of 20 weeks. No procedure-related complications or maternal complications were observed. The survival rate was higher and perinatal outcomes were better in fetoscopic laser coagulation cases than in other management cases. Four donor and four recipient triplets survived, with a median gestational age of 33 weeks at delivery. Although there were no cases of poor neonatal outcomes, one case was diagnosed with white matter injury, suspected to be hypoxic-ischemic encephalopathy on postnatal investigation.

CONCLUSION

Fetoscopic laser coagulation is a feasible treatment option for triplet TTTS, provided the attending specialists have extensive experience with this technique.

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 outcomes of fetoscopic laser surgery for twin-twin transfusion syndrome in triplet pregnancy: cohort study, systematic review and meta-analysis

OBJECTIVES

The aims of this study were to investigate the perinatal outcome of dichorionic triamniotic (DCTA) and monochorionic triamniotic (MCTA) triplet pregnancies complicated by twin-twin transfusion syndrome (TTTS) treated with fetoscopic laser photocoagulation (FLP) in two academic fetal centers, and to conduct a systematic review of previously published data to investigate perinatal survival in this targeted population.

METHODS

The first part of the study was a retrospective cohort study of prospectively collected data of consecutive triplet pregnancies with TTTS that underwent FLP at two fetal treatment centers between 2012 and 2020. Demographic, preoperative and operative variables and postoperative outcome were collected. Perinatal outcomes were investigated. The second part of the study was a systematic review and meta-analysis of studies evaluating the outcome of DCTA and/or MCTA triplet pregnancies, including our cohort study. PubMed, Web of Science and Scopus were searched from inception to September 2020. Primary outcomes were fetal survival (survival to birth), neonatal survival (survival to 28 days of age) and gestational age (GA) at birth.

RESULTS

A total of 31 sets of triplets with TTTS managed with FLP were included in the cohort study. Of these, 24 were DCTA and seven were MCTA. There were no significant differences in preoperative and operative variables between the two groups. There were also no significant differences between groups in GA at delivery or perinatal survival rate, including fetal and neonatal survival of at least one triplet, at least two triplets and all three triplets. Nine studies, including our cohort study, were included in the systematic review (156 DCTA and 37 MCTA triplet pregnancies treated with FLP). The overall fetal and neonatal survival was 79% (95% CI, 75-83%) and 75% (95% CI, 71-79%), respectively, in DCTA cases and 74% (95% CI, 52-92%) and 71% (95% CI, 49-89%), respectively, in MCTA cases. The rate of preterm birth before 28 weeks and before 32 weeks' gestation was 14% (95% CI, 4-29%) and 61% (95% CI, 50-72%), respectively, in DCTA triplets and 21% (95% CI, 3-45%) and 82% (95% CI, 62-96%), respectively, in MCTA triplets.

CONCLUSIONS

Triplet pregnancies with TTTS are at high risk of adverse perinatal outcome and preterm birth, regardless of chorionicity. The rate of survival after FLP in MCTA triplets was higher in our study than that reported in previous studies and is currently comparable with survival in DCTA triplets, which could be due to improved surgical skills. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Intrafetal laser therapy in a monochorionic diamniotic triplet pregnancy with two acardiac fetuses: a case report and literature review

Background

Monochorionic diamniotic triplet pregnancies are rare. Twin reversed arterial perfusion sequence in monochorionic triplet pregnancies is extremely rare, and it is associated with high perinatal morbidity and mortality rates in the “pump fetus.”

Case presentation

We reported a case of monochorionic diamniotic triplet pregnancy with twin reversed arterial perfusion sequence, including two acardiac fetuses sharing a single amniotic sac and a normal fetus in another amniotic sac. Due to rapid growth of the acardiac fetuses, intrafetal laser therapy was performed in both of them under ultrasound guidance at 15 weeks +5 days. Subsequently, regular and careful antenatal care including fetal ultrasonography and doppler and fetal echocardiography was conducted. At 37 weeks +4 days, a healthy female baby weighing 2510 g was delivered. The baby was followed up and now at 11 months old is in good health.

Conclusions

Twin reversed arterial perfusion sequence in monochorionic triplet pregnancy should be diagnosed early by ultrasound imaging during pregnancy. Individualized management should be based on clinical conditions to improve the perinatal outcome of the pump twin. Intrafetal laser therapy could be an alternative procedure when intrauterine intervention is required.

Expectant Management of Monochorionic-Triamniotic Triplets Complicated by Selective In Utero Growth Restriction: Report of 2 Cases

The optimal management of monochorionic-triamniotic (MCTA) triplet pregnancies is not clearly established, and there is no literature to guide management of MCTA complicated with selective intrauterine growth restriction (sIUGR). This gap in knowledge and the concern for higher risk of severe complications have led some medical societies to recommend selective termination of nontrichorionic triplet pregnancies. We sought to report the favourable outcomes of two MCTA complicated by sIUGR expectantly managed at Sainte-Justine Hospital, Montreal, Canada. The first case is of a 42-year-old woman with spontaneous MCTA triplets diagnosed at 18 weeks with type II sIUGR who opted for expectant management. The second patient was a 22-year-old woman with a spontaneous MCTA triplet pregnancy diagnosed at 18 weeks with type III sIUGR. Our experience shows that close serial ultrasounds could potentially allow physicians to foresee fetal deterioration. In our opinion, expectant management should be considered as a management option for MCTA complicated by sIUGR.

Endoscopic Placental Laser Coagulation in Dichorionic and Monochorionic Triplet Pregnancies

OBJECTIVE

To report the outcome of monochorionic (MC) and dichorionic (DC) triamniotic (TA) triplet pregnancies treated with endoscopic laser coagulation of the communicating placental vessels for severe feto-fetal transfusion syndrome (FFTS) and selective fetal growth restriction (sFGR).

METHODS

Laser surgery was performed at 18 (15-24) weeks' gestation in 11 MCTA and 33 DCTA pregnancies complicated by FFTS and 14 DCTA pregnancies complicated by sFGR. Data from our study and previous reports were pooled using meta-analytic techniques.

RESULTS

Survival of at least one baby and survival among all fetuses was 97.0 and 72.7% in DCTA pregnancies with FFTS, 78.6 and 52.4% in DCTA pregnancies with sFGR and 81.8 and 39.4% in MCTA pregnancies with FFTS. In the combined data from our study and previous reports, the pooled survival rates in 132 DCTA pregnancies with FFTS were 94.4 and 76.1%, and in 29 MCTA pregnancies with FFTS, they were 80.6 and 57.5%.

CONCLUSIONS

Survival after laser surgery is higher in DC triplets with FFTS than in those with sFGR and in DC than in MC triplets with FFTS.

[Outcome of triplet pregnancies managed for twin-to-twin transfusion syndrome: A single center experience]

OBJECTIVES

Study the outcomes of triplet pregnancies (GGG) complicated with twin-to-twin transfusion syndrome (TTTS) treated with laser fetoscopy.

METHODS

Retrospective study of interventions, outcomes and perinatal follow-up of GGG treated for TTS.

RESULTS

Between 2002 and 2013, 25 GGG complicated by TTTS were seen in our center, 20 dichorionic and 5 monochorionic. The mean gestational age (GA) at diagnosis of TTTS was 19.7 GW (±2.4) with 2, 4, 16 and 1 pregnancies at Quintero's stage I, II, III and V, respectively. They had a fetoscopy at an average GA of 19 GW and 6 days. There were 3 (13.0%) late miscarriages. The average GA at delivery was of 29.6 GW overall (26.3 GW and 31.1 GW in monochorionic and dichorionic pregnancies respectively). The overall fetal survival rate was 57.97% (40% and 66.7% in the group of monochorionic dichorionic pregnancies, respectively). However, neonatal mortality (<28 days) is 17.5%.

CONCLUSION

GGG operated by fetoscopy for TTTS have a survival rate of three, at least 2 and at least 1 fetus of 21.7%, 69.6% and 82.6% respectively. The overall fetal survival rate is 59.97%. There is a tendency for better survival rates in dichorionic GGG compared to monochorionic GGG (P=0.079).

Incidences of Feto-Fetal Transfusion Syndrome and Perinatal Outcomes in Triplet Gestations with Monochorionic Placentation

INTRODUCTION

This study aimed to determine the incidences of feto-fetal transfusion syndrome (FFTS) and perinatal outcomes in triplet gestations with monochorionic placentation.

MATERIALS AND METHODS

In this retrospective cohort study, we evaluated the incidences of FFTS and perinatal outcomes at 28 days of age in cases of triplet gestations with monochorionic placentation who visited our centers before 16 weeks of gestation and delivered over a period of 11 years.

RESULTS

In 41 triplet gestations (17 monochorionic triamniotic, 22 dichorionic triamniotic, 1 dichorionic diamniotic, and 1 monochorionic monoamniotic), the incidence of FFTS was 17.1%, and the median gestational age at FFTS diagnosis was 19 weeks. In 123 triplets, the incidences of fetal death and neonatal death at 28 days of age were 8.1 and 0.9%, respectively. None of the surviving infants had grade 3 or 4 intraventricular hemorrhage, while cystic periventricular leukomalacia occurred in 6 of 113 infants (5.3%). The incidence of poor outcomes (death or any major neurological complication at 28 days of age) was 13.8%.

DISCUSSION

Seventeen percent of triplet pregnancies with monochorionic placentation developed FFTS, and 14% had a poor outcome. Therefore, triplet gestations with monochorionic placentation should be followed carefully.

Fetofetal Transfusion Syndrome in Monochorionic-Triamniotic Triplets Treated with Fetoscopic Laser Ablation: Report of Two Cases and A Systematic Review

Objective This study aims to determine the clinical outcomes of monochorionic-triamniotic (MT) pregnancies complicated by severe fetofetal transfusion undergoing laser photocoagulation. Study Design We report two cases of MT triplets complicated by fetofetal transfusion syndrome (FFTS) and a systematic review classifying cases into different subtypes: MT with two donors and one recipient, MT with one donor and two recipients, MT with one donor, one recipient, and one unaffected triplet. The number of neonatal survivors was analyzed based on this classification as well as Quintero staging. Results A total of 26 cases of MT triples complicated by FFTS were analyzed. In 56% of the cases, the FFTS involved all three triplets, 50% of whom had an additional donor and 50% an additional recipient. Among the 24 cases that survived beyond 1 week after the procedure, the average gestational age of delivery was 29.6 weeks, and the average interval from procedure to delivery was 10.1 weeks. The overall neonatal survival rate was 71.7%, with demises occurring equally between donor and recipient triplets. Overall neonatal survival including survival of at least two fetuses occurred with equal frequency between the different groups. Conclusion Significant neonatal survival can be achieved in most cases of MT triplets with FFTS.

Perinatal outcome after laser surgery for triplet gestations with feto-fetal transfusion syndrome

OBJECTIVE

The objective of this study is to evaluate the outcomes of fetoscopic laser photocoagulation (FLP) for a triplet gestation with feto-fetal transfusion syndrome (FFTS).

METHOD

On the basis of chorionicity, perinatal outcome at 28 days in triplets with FFTS after FLP were evaluated.

RESULTS

Fetoscopic laser photocoagulation was completed for all 16 cases including nine dichorionic triamniotic (DT) cases and seven monochorionic triamniotic (MT) cases. The placenta was located anteriorly in six cases. The median gestational age at surgery was 21 (16-25) weeks, and the median operation time was 51 (25-125) minutes. Several technical maneuvers to complete the procedure in MT, such as trocar assistance in two cases, intentional septostomy of the dividing membrane in one, and double uterine entry in one, were used. The median gestational age at delivery was 31 (23-34) weeks. Overall perinatal survival in DT was 74% and that of MT was 95%. All 16 cases resulted in at least one survival, whereas three neonates survived in 44% of DT cases and in 86% of MT cases. Two MT neonates suffered severe intraventricular hemorrhages.

CONCLUSIONS

Fetoscopic laser photocoagulation for FFTS in MT as well as DT triplets seems a valuable treatment.

Twin–Twin Transfusion Syndrome and Twin Anemia–Polycythemia Sequence in a Monochorionic Triamniotic Pregnancy

Twin–twin transfusion syndrome (TTTS) is an antenatal complication of monochorionic multiple gestations. There have been few studies exploring the role of laser photocoagulation or outcomes following treatment in monochorionic triplet pregnancies with TTTS. We present a case where TTTS and twin anemia–polycythemia sequence (TAPS) complicated a monochorionic triplet pregnancy. Following the laser photocoagulation to treat the TTTS between the triplets, an intra-uterine death occurred in one triplet and TAPS developed in the remaining two triplets. Intervention in this case resulted in a 2-week prolongation of pregnancy and a positive outcome for the remaining fetuses. This case and other published data reviewed in this article suggest that laser photocoagulation has a potential role for TTTS in monochorionic triplet pregnancies.

Maternal complications of fetoscopic laser photocoagulation (FLP) for treatment of twin-twin transfusion syndrome (TTTS)

AIMS

Fetoscopic laser photocoagulation (FLP) has become standard therapy for severe twin-twin transfusion syndrome. Data on adverse maternal events are rare. We performed a literature review to obtain data on maternal complications of FLP.

METHODS

Extensive literature review, searching MEDLINE and other databases from 1990 to 2009, using MESH-terms and further keywords. Data extraction was performed using the following criteria: (i) maternal complications reported as primary or secondary outcome parameters; (ii) any comment on adverse maternal events.

RESULTS

Of 321 publications found 40 were included, comprising 1785 patients. The overall rate of adverse maternal events was 5.4%. In studies with systematic assessment (n=3, 379 patients) the complication rate was significantly higher (17.4% vs. 2.2%, P<0.0001). Adverse events were classified and the rate was 1.0% (1.8% vs. 0.8%, P=0.12) for severe complications; 2.9% (11.9% vs. 0.5%, P<0.0001) for intermediate/minor adverse events; and 1.5% (3.7% vs. 0.9%, P<0.0001) for complications with undetermined relevance.

CONCLUSIONS

High-quality data on maternal complications of FLP are rare. With systematic assessment, the rate of adverse events is significantly higher. Underreporting has to be assumed. Further studies are required to confirm these data.

Laser therapy of twin-to-twin transfusion syndrome in triplet pregnancies

OBJECTIVE

Laser coagulation of placental anastomoses in twin pregnancies complicated by severe twin-to-twin transfusion syndrome (TTTS) has been shown to be superior to serial amniodrainage, and has emerged as the standard therapy for this condition. We report the outcome of triplet pregnancies treated with laser therapy for severe TTTS.

METHODS

From a database containing information on all multiple pregnancies referred to our center we identified 20 triplet pregnancies with severe TTTS. Sixteen of them were dichorionic, four monochorionic and all cases were triamniotic. Perinatal outcome was obtained in all cases.

RESULTS

Fetoscopy was performed in 18 out of 20 cases at a median gestational age of 19.7 (range, 17.0-23.3) weeks. Delivery occurred at a median of 31.9 (range, 24.7-36.4) weeks with an overall fetal survival rate of 65%, at least one surviving fetus in 83% of cases and all three fetuses surviving in 39%.

CONCLUSION

Laser coagulation is an effective treatment for severe TTTS in triplets. However, survival rates are lower than in twin pregnancies.

Early diagnosis, follow-up, and prenatal treatment of a case of TRAP sequence occurring in a dichorionic triamniotic triplet pregnancy

We are reporting a case of twin reversed arterial perfusion (TRAP) sequence occurring in a dichorionic triamniotic triplet pregnancy with successful percutaneous prenatal treatment and excellent neonatal outcome. TRAP sequence was diagnosed at 11 weeks in a spontaneous dichorionic-triamniotic triplet. Sonographic assessment showed persistent arterial flow and development of hydrops in the acardiac twin. Percutaneous cord interstitial laser coagulation was performed, and the co-twin subsequently developed growth restriction. The 9-month-old twins have a normal developmental course. This report confirms that fetal intervention is indicated in cases of TRAP sequence in which the acardiac twin presents a significant enlargement on follow-up sonographic examinations.

Umbilical cord occlusion for selective feticide in complicated monochorionic twins: a systematic review of literature

The aim of this study was to review literature concerning selective feticide (SF) in monochorionic pregnancies complicated with twin-twin transfusion syndrome, twin reversed arterial perfusion, severe malformation, and discordant growth. The remaining twins' outcomes were stratified for indication and surgical technique. Three hundred forty-five cases of SF were reviewed. Premature rupture of membranes was described in all the procedures and complicated 76/345 (22%) pregnancies within 4 postoperative weeks (59%) or later (41%; P = .52). Fetal demise accounted for 51/345 (15%), more frequently within 2 postoperative weeks (79%) than thereafter (21%; P = .004; odds ratio [OR], 6.12; 95% confidence interval [CI], 1.81-20.70). Improved survival rate was achieved in surgeries after 18 weeks (89%) than earlier (69%; P = .02; OR, 0.28; 95% CI, 0.10-0.80) without differences for indication. Survivors were 86% after radiofrequency ablation, 82% after bipolar cord coagulation, 72% after laser cord coagulation, 70% after cord ligation. In spite of favorable outcomes, the optimal surgical approach remains undetermined.

An Experience of Laser Surgery for Feto-Fetal Transfusion Syndrome Complicated with Unexpected Feto-Fetal Hemorrhage in a Case of Monochorionic Triamniotic Triplets

Feto-fetal transfusion syndrome (FFTS) in monochorionic triplets is a rare clinical entity which may share the principal adverse perinatal outcomes of twin-twin transfusion syndrome. Recently, favorable prognoses regarding morbidity and mortality in twins after selective laser photocoagulation of placental communicating vessels (SLPCV) have been described. But descriptions of this procedure in monochorionic triplet cases are limited. This is the case report of an experience of SLPCV applied to monochorionic triamniotic triplets with FFTS. Triplet A had polyhydramnios, while absent end-diastolic flow in the umbilical artery of triplet B, the triplet with anhydramnios, was persistent. Triplet C looked normal, vertical amniotic pocket and Doppler studies yielding normal results. At the beginning of the SLPCV procedure, feto-fetal hemorrhage, subsequent to the fetal death of the donor triplet, occurred. Both surviving cofetuses showed persistent bradycardia; and 1 fetus died while the other recovered from the fetal bradycardia. All vascular anastomoses between the 3 triplets could be identified and obliterated, requiring two trocars. Our fetoscopic observation revealed feto-fetal hemorrhage after demise of monochorionic triplet, which led to injury of other fetuses due to hypovolemia in an instant. In conclusion, SLPCV might be a valid option for FFTS in triplet cases, while further experience is required in order to evaluate the risks and benefits of this procedure in triplet cases.

Comparison of Pregnancy Course and Outcome with Color and Radiographic Angiography of the Placenta in a Monochorionic Triplet Pregnancy

A patient with spontaneous monochorionic (MC) triamniotic triplet pregnancy developed symptoms of feto-fetal-transfusion-syndrome (FFTS) at 18 weeks of gestation with one donor (oligohydramnios) and one receptor (polyhydramnios) triplet. The patient "received" a diet enriched with proteins. Amniotic-fluid volume returned to normal after 24 weeks. At 32 weeks, a Cesarean section was performed due to intra-uterine growth restriction of the donor triplet. Post partum color injection and computer angiograms showed arterio-arterial (AA) anastomoses between all triplets. Deep arterio-venous (AV) anastomoses between the two triplets who had demonstrated with oligo- and polyhydramnios between 18 and 26 weeks were revealed by computer angiography that were not seen by placental color angiogram. Detailed analysis of placental vascular communications by use of color injection angiogram of the chorionic plate and computer angiogram demonstrating deep anastomoses beneath the chorionic plate helps to understand the individual pathophysiology and clinical course in patients with FFTS, which is even more complex in MC triplet compared to MC twin pregnancies.

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

OBJECTIVE

This study was undertaken to document pregnancy and infant outcome after cord coagulation with laser and/or bipolar as a technique for selective feticide in complicated monochorionic multiple pregnancies.

STUDY DESIGN

Prospective follow-up study in 2 tertiary fetal medicine centers.

RESULTS

Eighty cases were included in the study (73 twins, 7 triplets). The survival rate was 83% (72/87). There were 9 intrauterine fetal deaths (10%), 5 within 24 hours and 4 between 4 and 10 weeks after the procedure. There was 1 termination of pregnancy because of chorioamnionitis. Median gestational age at delivery was 35.4 weeks, with 79% of patients delivering after 32 weeks. Preterm prelabor rupture of the membranes before 25 weeks accounted for all perinatal deaths (n = 5). Of the children older than 1 year of age (n = 67), 62 (92%) have a normal development.

CONCLUSION

Cord coagulation is an effective method for selective feticide in monochorionic multiple pregnancies.

Managing twins discordant for fetal anomaly

An excess of structural anomalies is observed in twins compared to singletons. Approximately 1-2% of twin pregnancies may face the dilemma of expectant management versus selective termination following diagnosis of an anomaly affecting only one fetus. If the option of selective fetocide is considered, the main variable determining the technique to achieve this aim is chorionicity. In a dichorionic pregnancy, passage of substances from one twin into the circulation of the co-twin is unlikely due to the lack of placental anastomoses, hence KCl can be injected safely into the circulation of the affected twin to produce fetal asystole. In monochorionic twin pregnancies, selective termination needs to be performed by ensuring complete and permanent occlusion of both the arterial and venous flows in the umbilical cord of the affected twin, in order to avoid acute haemorrhage from the co-twin into the dying fetus, which may lead to death or organ damage. Bipolar cord coagulation under ultrasound guidance is associated with approximately 70-80% survival rates.

Management of fetofetal transfusion syndrome

Feto-fetal transfusion syndrome contributes heavily to high rates of perinatal mortality and morbidity in monochorionic multiple pregnancies. Its prenatal management has been controversial for at least 25 years. We review the recent literature in order to present the basis for a pragmatic reappraisal of the management of this condition. Laser surgery of the chorionic plate inter-twin anastomoses is the best first-line treatment when the syndrome develops before 26 weeks' gestation. Survival (including quality of survival) and gestational age at delivery are improved when compared to serial amnioreduction. Second-line treatment options include repeat-laser, intra-uterine blood transfusion, serial amnioreduction, selective feticide using bipolar cord coagulation or elective delivery, depending upon gestational age and the severity of the disease and its complications. We have found that fetoscopic placental surgery has proven itself over simplicity of amnioreduction. There is no evidence that treatment should be customized according to the stage of the disease at diagnosis. Early recognition of the syndrome through fortnightly serial ultrasound follow-up of all monochorionic pregnancies should ensure timely referral and make up for geographical constraints. Laser surgery should now be available in fetal medicine units that are managing at least 20 cases per year.