Selective reduction in complicated monochorionic twins: prediction of obstetric outcome and comparison of techniques

Clinical Outcome of Monochorionic Diamniotic Twins with Intrauterine Growth Restriction

OBJECTIVE

This study investigated the clinical outcome of monochorionic diamniotic (MCDA) twins with selective intrauterine growth restriction (sIUGR).

STUDY DESIGN

International Peace Maternal and Child Health Hospital of Shanghai ultrasound database was investigated to identify all MCDA delivered from January 2013 to December 2017. After identifying 43 pairs of MCDA twins with sIUGR and 282 pairs of normal MCDA twins, we compared clinical outcomes between the two groups.

RESULTS

Compared with normal twins, sIUGR fetuses had significantly shorter gestational age at delivery, smaller average birth weight of both twins, more significant intertwin difference in birth weight, lower Apgar scores, and higher intrauterine fetal demise (IUFD) rate, and smaller placental weight. The rate of abnormal umbilical cord insertions and abnormal blood flow in the ductus venosus (DV) and middle cerebral artery (MCA) is significantly higher in the sIUGR group. In addition, the subtype analysis of sIUGR groups indicated the poorest outcomes in type II with no significant difference between type I and III.

CONCLUSION

MCDA twins with sIUGR generally exhibited limited clinical outcomes than normal MCDA twins. These limitations are mainly associated with abnormal umbilical cord insertions and blood flow in the DV and MCA. Clinical outcomes differed among the three types of sIUGR, with type II having the worst prognosis and the highest IUFD rate.

KEY POINTS

· sIUGR generally exhibited limited clinical outcomes than normal MCDA twins.. · These limitations are mainly associated with blood flow of the DV and MCA.. · sIUGR with type II has the worst prognosis and the highest IUFD rate..

Consensus protocol for management of early and late twin-twin transfusion syndrome: Delphi study

OBJECTIVE

Fetoscopic laser photocoagulation (FLP) is a well-established treatment for twin-twin transfusion syndrome (TTTS) between 16 and 26 weeks' gestation. High-quality evidence and guidelines regarding the optimal clinical management of very early (prior to 16 weeks), early (between 16 and 18 weeks) and late (after 26 weeks) TTTS are lacking. The aim of this study was to construct a structured expert-based clinical consensus for the management of early and late TTTS.

METHODS

A Delphi procedure was conducted among an international panel of experts. Participants were chosen based on their clinical expertise, affiliation and relevant publications. A four-round Delphi survey was conducted using an online platform and responses were collected anonymously. In the first round, a core group of experts was asked to answer open-ended questions regarding the indications, timing and modes of treatment for early and late TTTS. In the second and third rounds, participants were asked to grade each statement on a Likert scale (1, completely disagree; 5, completely agree) and to add any suggestions or modifications. At the end of each round, the median score for each statement was calculated. Statements with a median grade of 5 without suggestions for change were accepted as the consensus. Statements with a median grade of 3 or less were excluded from the Delphi process. Statements with a median grade of 4 were modified according to suggestions and reconsidered in the next round. In the last round, participants were asked to agree or disagree with the statements, and those with more than 70% agreement without suggestions for change were considered the consensus.

RESULTS

A total of 122 experts met the inclusion criteria and were invited to participate, of whom 53 (43.4%) agreed to take part in the study. Of those, 75.5% completed all four rounds. A consensus on the optimal management of early and late TTTS was obtained. FLP can be offered as early as 15 weeks' gestation for selected cases, and can be considered up to 28 weeks. Between 16 and 18 weeks, management should be tailored according to Doppler findings.

CONCLUSIONS

A consensus-based treatment protocol for early and late TTTS was agreed upon by a panel of experts. This protocol should be modified at the discretion of the operator, according to their experience and the specific demands of each case. This should advance the quality of future studies, guide clinical practice and improve patient care. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Outcome of monochorionic diamniotic twin pregnancy with selective intrauterine growth restriction, a single center study in China

INTRODUCTION

This retrospective study aimed to evaluate clinical outcomes of monochorionic diamniotic (MCDA) twins with selective intrauterine growth restriction (sIUGR).

MATERIALS AND METHODS

MCDA twins, either sIUGR and non-sIUGR, underwent expectant management from 2016 to 2019 in our hospital were included. sIUGR fetuses were classified into three types according to umbilical artery Doppler assessment. Non-sIUGR were considered as the control group. Outcomes were pregnancy outcomes and maternal complications.

RESULTS

Forty-three sIUGR (type I: 23; type II: 14, and type III: 6) and 282 non-sIUGR fetuses were included. The sIUGR group had a significantly earlier birth, lower birth weight of the twins, larger inter-twin weight difference, lower Apgar score of the twins, and higher intrauterine fetal death (IUFD) than the non-sIUGR group (all p < 0.001). The same trend was found in the sIUGR type II group compared to type I and III groups. A significantly lower gestational diabetes rate (p = 0.01) and placenta weight (p < 0.001), and higher proportions of abnormal placental umbilical cord insertion (p < 0.001), and ultrasound Doppler monitoring indicators (p = 0.006) were found in the sIUGR group than the non-sIUGR group.

CONCLUSIONS

The MCDA twins with sIUGR showed poorer outcomes than the non-sIUGR group. Doppler interrogation was a useful clinical marker for fetal outcome.

Fetal growth disorders in twin gestations

PURPOSE OF REVIEW

Twin gestations account for approximately 3% of all births. Although there appear to be physiologic differences in the third trimester growth of twins compared with singleton gestations, reasons for this remain unclear. As growth-restricted fetuses and neonates are at increased risk for adverse outcomes, there is a clinical need to optimize our ability to delineate normally from pathologically grown twins.

RECENT FINDINGS

Recent studies have addressed current limitations in the way growth restriction is diagnosed in twin gestations. Twin-specific fetal and neonatal growth charts have been shown to decrease the number of cases inappropriately labeled as growth restricted compared with singleton nomograms. In addition, individual growth assessment (IGA) is a promising method of diagnosing pathological growth using each fetus's growth potential rather than a comparison of the estimated fetal weight with population nomograms.

SUMMARY

There is a recent focus on improving our understanding of physiologic and pathologic twin growth. The increased use of twin-specific growth curves is likely to result in a decrease in the incidence of FGR diagnosis among twin gestations and could improve the outcomes of twins currently misclassified as FGR. Future research will hopefully clarify the reasons behind differences seen in twin versus singleton third trimester twin growth.

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.

Co-twin survival after selective fetal reduction in complicated multiple gestations: A systematic review and meta-analysis of survival rate according to indication for intervention

OBJECTIVE

Determine the impact of indication for selective reduction (SR) on co-twin survival in monochorionic gestations undergoing radiofrequency ablation (RFA) or bipolar cord coagulation (BCC).

METHODS

PubMed and Web of Science were systematically searched from inception of databases to April 2021. Frequency of indications was compared between post-intervention co-twin survival and demise groups undergoing SR. Random-effect model was used to pool mean differences or odds ratios (OR) and corresponding 95% confidence intervals (CIs). Heterogeneity was assessed using the I² value.

RESULTS

Of 1060 studies assessed for eligibility, nine studies met criteria. A total of 666 pregnancies underwent RFA (n = 483 co-twin survival) and 235 pregnancies underwent BCC (n = 188 co-twin survival). Twin twin transfusion syndrome (TTTS), as an indication for RFA, was associated with decreased co-twin survival (OR 0.61, 95% CI 0.41, 0.90, P 0.01, I² 0.0%). Other indications for RFA were not associated with significant difference in co-twin survival. With BCC, none of the indications were found to significantly influence the co-twin survival following intervention.

CONCLUSION

RFA was found to have lower co-twin survival when performed for TTTS. No other indications was associated with differences in co-twin survival. BCC was not associated with any differences in co-twin survival based on indication.

Correlation analysis of adverse outcomes for the selective reduction of twin pregnancies

BACKGROUND

Due to the extensive development of assisted reproductive technology, the number of twin pregnancies has increased significantly over recent decades. Twin pregnancy is the most representative type of multiple pregnancies and is associated with high infant morbidity and mortality. Perinatal complications of twin pregnancy are also markedly increased compared with those of single pregnancy. Transabdominal selective reduction (SR) is a remedial intervention. This study aimed to research the adverse outcomes of transabdominal selective reduction of twin pregnancy and the correlation between the reduction week and pregnancy outcomes.

OBJECTIVE

The purpose of this study was to examine the adverse outcomes of the transabdominal selective reduction of twin pregnancy and the correlation between the reduction week and pregnancy outcomes.

METHODS

A retrospective cohort study of the transabdominal reduction of twin pregnancy was conducted in a single prenatal diagnosis medical centre from September 2012 to October 2020. According to chorionicity, women with twin pregnancies were divided into 2 groups: dichorionic (DC) twin pregnancies and monochorionic (MC) twin pregnancies. Women with DC twin pregnancies underwent potassium chloride reduction, and those with MC twin pregnancies underwent radiofrequency ablation (RFA). The reduction indications included pregnancy complications, foetal abnormalities, and maternal factors. The perinatal outcomes of different chorionic twins after reduction were analysed. Each foetus with an adverse outcome was included. The relative relationship between the reduction weeks and delivery weeks of twins was examined by correlation analysis.

RESULTS

A total of 161 women were included in this study. A total of 112 women had DC twin pregnancies, and 49 women had MC twin pregnancies. Preterm delivery rates were significantly higher in the MC twin reduction group than in the DC twin reduction group prior to 37 weeks (53.1% vs. 29.5%, P = 0.004). The mean gestational age at delivery of the foetuses in the DC twin group that underwent SR was significantly older than that of those in the MC twin group that underwent SR (36.9 ± 4.0 vs. 33.5 ± 6.6 weeks, P = 0.001). The number of DC twins that underwent SR and were delivered after 37 weeks was obviously greater than that of the MC twins that underwent SR (70.5% vs. 46.9%, P = 0.004). The foetal survival rate was 95.5% in the DC twin reduction group and 77.6% in the MC twin reduction group. If the indication of TTTS was not included, there was no significant difference in the foetal survival rate of the DC and MC twin reduction groups (95.5% vs. 86.2%, P = 0.160). Cotwin death 1 week after reduction was greater in the MC group (6.1% vs. 0%, P = 0.027). Compared to other indications, this finding indicated that a significantly lower proportion of women remained undelivered after selective reduction with the indication of TTTS. There was a significant negative correlation between the reduction weeks and delivery weeks of the two groups (P < 0.01), and the best opportunity for reduction was before 22 weeks of gestation.

CONCLUSION

These findings highlighted an obviously negative correlation between the reduction week and delivery week. The transabdominal selective reduction of twin pregnancy should be considered for a lower rate of miscarriage or premature delivery if the reduction week takes place earlier in pregnancy. The rate of preterm delivery was the lowest when transabdominal selective reduction was completed before 22 weeks of gestation. Compared with other RFA indications, a higher rate of premature delivery was shown for MC twins with a reduction indication of TTTS. TTTS with sIUGR might be one of the reasons for the adverse outcomes of reduction for MC twin pregnancy.

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.

Fetoscopic Laser Ablation for the Selective Fetal Reduction in Twin-Twin Transfusion Syndrome Stage II-IV: The Experience of a New Fetal Medicine Center

Objective

To evaluate the surgery outcomes of fetoscopic laser ablation (FLA) for selective umbilical cord in treating twin-twin transfusion syndrome (TTTS) with special conditions and neonatal outcomes post-operation.

Methods

A prospective study, 21 monochorionic diamniotic (MCDA) twins diagnosed with TTTS stage II–IV according to Quintero classification from 16 to 26 weeks of gestation, among that, 12 cases of TTTS stage II with selective intrauterine growth restriction (sIUGR), 6 cases of TTTS stage II with proximate cord insertions, 3 cases of TTTS stage IV underwent fetoscopic laser ablation for the selective fetal reduction at Hanoi Obstetrics and Gynecology Hospital from September 2019 to July 2021. Complications and surgical outcomes were noted. Prenatal care was carried out every 2 weeks post operation until birth. Newborn neurologic complications were assessed at birth, three months, and six months after birth using Denver II test and magnetic resonance imaging (MRI).

Results

The mean gestational age at operation was 20.30 weeks. The average operation duration was 39.52 minutes. No complications of operation, such as bleeding or infection, were recorded. The mean gestational age at birth was 34.70 ± 4.33 weeks, with a mean duration of 12.97 ± 6.87 weeks between intervention and delivery. The survival rate of newborns after the operation was 90.48%. There were two stillbirths (9.52%) within seven days after the operation. No short-term neurological complications have been reported with follow-up of the newborn to 6 months after birth.

Conclusion

Our study showed that fetoscopic laser ablation of selected fetal reduction surgery for treatment of special conditions of TTTS had no complications of operation, high neonatal survival result (90.48%), no short-term neurological complications. This should be considered for TTTS in cases of indication.

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.

Understanding Sociodemographic Disparities in Maternal-Fetal Surgery Study Participation

BACKGROUND/PURPOSE

Although maternal-fetal surgery to treat fetal anomalies such as spina bifida continues to grow more common, potential health disparities in the field remain relatively unexamined. To address this gap, we identified maternal-fetal surgery studies with the highest level of evidence and analyzed the reporting of participant sociodemographic characteristics and representation of racial and ethnic groups.

METHODS

We conducted a systematic review of the scientific literature using biomedical databases. We selected randomized control trials (RCTs) and cohort studies with comparison groups published in English from 1990 to May 5, 2020. We included studies from across the globe that examined the efficacy of fetal surgery for twin-twin transfusion syndrome (TTTS), obstructive uropathy, congenital diaphragmatic hernia (CDH), myelomeningocele (MMC), thoracic lesions, cardiac malformations, or sacrococcygeal teratoma. We determined the frequency of reporting of age, gravidity/parity, race, ethnicity, education level, language spoken, insurance, income level, and relationship status. We identified whether sociodemographic factors were used as inclusion or exclusion criteria. We calculated the racial and ethnic group representation for studies in the USA using the participation-to-prevalence ratio (PPR).

RESULTS

We included 112 studies (10 RCTs, 102 cohort) published from 1990-1999 (8%), 2000-2009 (30%), and 2010-2020 (62%). Most studies were conducted in the USA (47%) or Europe (38%). The median sample size was 58. TTTS was the most common disease group (37% of studies), followed by MMC (23%), and CDH (21%). The most frequently reported sociodemographic variables were maternal age (33%) and gravidity/parity (20%). Race and/or ethnicity was only reported in 12% of studies. Less than 10% of studies reported any other sociodemographic variables. Sociodemographic variables were used as exclusion criteria in 13% of studies. Among studies conducted in the USA, White persons were consistently overrepresented relative to their prevalence in the US disease populations (PPR 1.32-2.11), while Black or African-American, Hispanic or Latino, Asian, American-Indian or Alaska-Native, and Native-Hawaiian or other Pacific Islander persons were consistently underrepresented (PPR 0-0.60).

CONCLUSIONS

Sociodemographic reporting quality in maternal-fetal surgery studies is poor and inhibits examination of potential health disparities. Participants enrolled in studies in the USA do not adequately represent the racial and ethnic diversity of the population across disease groups.

Selective termination of the fetus in multiple pregnancies using ultrasound-guided radiofrequency ablation

Background

To evaluate the perinatal outcomes in women with selective termination using ultrasound-guided radiofrequency ablation (RFA).

Methods

Complicated monochorionic (MC) twin pregnancies and multiple pregnancies with an indication for selective termination by ultrasound-guided coagulation of the umbilical cord with RFA under local anesthesia between July 2013 and Jan 2020 were reviewed. We analyzed the indications, gestational age at the time of the procedure, cycles of RFA, duration of the procedure, and perinatal outcome.

Results

Three hundred and thirteen patients were treated during this period. Seven of whom were lost of follow-up. The remaining 306 cases, including 266 pairs of monochorionic diamniotic (MCDA) twins (86.93%), two pairs of monoamniotic twins (0.65%), 30 dichorionic triamniotic (DCTA) triplets (1%), and three monochorionic triamniotic (MCTA) triplets (0.98%), were analyzed. Indications included twin-to-twin transfusion syndrome (TTTS) (n = 91), selective fetal growth restriction (sFGR) (n = 83), severe discordant structural malformation (n = 78), multifetal pregnancy reduction (MFPR) (n = 78), twin reverse arterial perfusion sequence (TRAPS) (n = 19), and twin anemia-polycythemia sequence (TAPS) (n = 3). Upon comparison of RFA performed before and after 20 weeks, the co-twin loss rate (20.9% vs. 21.5%), the incidence of preterm premature rupture of membranes (PPROM) within 24 h (1.5% vs. 1.2%), and the median gestational age at delivery [35.93 (28–38) weeks vs. 36 (28.54–38.14) weeks] were similar (p > 0.05).

Conclusions

RFA is a reasonable option when indicated in multiple pregnancies and complicated monochorionic pregnancies. In our experience, the overall survival rate was 78.76% with RFA in selective feticide, and early treatment increases the likelihood of survival for the remaining fetus because the fetal loss rate is similar before and after 20 weeks.

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.

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.

Perinatal outcome in monochorionic twin pregnancies after selective fetal reduction using radiofrequency ablation

OBJECTIVE

To study the perinatal outcomes in women with complicated monochorionic twin pregnancies undergoing selective fetal reduction using radiofrequency ablation (RFA).

METHODS

This retrospective study included 44 patients with monochorionic twin pregnancies, between 14 and 28 weeks of pregnancy, who underwent RFA for selective fetal reduction. Perinatal and maternal outcomes and procedure-related complications were analyzed.

RESULTS

The procedure was technically successful in all 44 cases. Indications for selective fetal reduction included twin-to-twin transfusion syndrome (52.3%), twin reversed arterial perfusion (20.5%), twins discordant for anomaly (15.9%), and selective fetal growth restriction (11.4%). Median gestational age at procedure was 22^2/7  weeks (range 14-26^6/7 ). Live birth rate was 77.3% with three neonatal deaths; so overall survival was 70.5%. Median procedure-to-delivery interval was 12^3/7  weeks (range 2^4/7 -23). There were eight losses before 24 weeks of pregnancy, which included two co-twin deaths. Median gestational age at delivery was 35 weeks (interquartile range 32^1/7 -37 weeks). The preterm delivery rate was 66.7% (24/36) and preterm prelabor rupture of membranes (PPROM) occurred in 22.7% (10/44) of patients.

CONCLUSION

Selective fetal reduction using RFA is safe and effective in complicated monochorionic pregnancies. However, the rates of PPROM and preterm delivery remain high.

A cohort study of the perinatal outcome of radiofrequency ablation in complicated monochorionic multiple pregnancies based on a different needle insert angle

OBJECTIVE

To compare the pregnancy outcomes of radiofrequency ablation (RFA) for complicated multiple pregnancies between fetal abdominal and dorsal needle insertion angles.

METHODS

We performed a historical cohort study of patients who underwent selective reduction using RFA through different needle insertion angles from 2015 to 2018 at a local hospital. Dorsal needle insertion cases were consecutively selected and abdominal needle insertion cases were selectively enrolled. The Cox proportional hazards model was constructed to identify predictors of fetal survival time with different needle insertion angles.

RESULTS

The RFA procedure was performed in 28 women through an abdominal insertion angle and in 28 women through a dorsal insertion angle. There were no significant differences in perinatal outcomes between the two groups. The overall live birth rate after RFA in the two groups was 73.5% and the mean gestation was 31.6 ± 6.5 weeks. The Cox model showed that gestational age at RFA was a predictor of the duration of the period between RFA and delivery.

CONCLUSION

RFA conducted through the dorsal insertion angle is technically feasible for selective reduction in complex monochorionic multiple pregnancies. Gestational age at this procedure is an independent risk factor for the duration of pregnancy post-RFA.

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.

Radiofrequency ablation for selective fetal reduction in complicated Monochorionic twins; comparing the outcomes according to the indications

Background

To evaluate the perinatal outcomes in women with complicated monochorionic diamniotic twins who underwent selective reduction using radiofrequency ablation (RFA).

Methods

This retrospective study included patients with complicated monochorionic diamniotic twins between 16 to 28 weeks who underwent selective reduction using RFA.

Results

During the study period, 143 women with complicated monochorionic twins underwent RFA including 52 with selective fetal growth restriction (sFGR), 48 with twin to twin transfusion syndrome (TTTS), 33 with major fetal anomalies in one of the twins, and 10 with reversed arterial perfusion sequence (TRAP). The overall survival was 71.3% (102/143). The procedures were technically successful in achieving selective termination in all cases. The mean ± SD of gestational age at the time of the procedure was 21.0 ± 2.3 weeks. The mean ± SD of gestational age at delivery was 34.6 ± 3.3 weeks. The mean ± SD of overall procedure-to-delivery time was 12 ± 1.7 weeks. The pregnancy success rates among sFGR, TRAP, TTTS and anomaly groups were 82.7, 80, 73 and 60.7% respectively. There were no maternal complications.

Conclusion

Radiofrequency ablation for fetal reduction in complicated monochorionic twin pregnancies appears to be a reasonable option. The pregnancy success rate following RFA selective reduction was highest among sFGR and TRAP groups and lowest in the anomaly group.

Influence of indications on perinatal outcomes after radio frequency ablation in complicated monochorionic pregnancies: a retrospective cohort study

Background

Radiofrequency ablation (RFA) is recommended to prevent potential neurological injury or intrauterine foetal death (IUFD) of the co-twin(s) in complicated monochorionic (MC) pregnancies. However, the impacts of various indications on the pregnancy outcome following RFA remain unclear. This study aimed to determine how the indications influence the perinatal outcomes in complicated MC pregnancies undergoing radiofrequency ablation.

Methods

This was a retrospective cohort study performed in a single centre. All consecutive MC pregnancies treated with RFA between July 2011 and July 2019 were included. The adverse perinatal outcomes and the survival rate were analysed based on various indications. The continuous variables with and without normal distribution were compared between the groups using Student’s t-test and Mann–Whitney U test, respectively, and for categorical variables, Chi-square and Fisher’s exact tests were used. P < 0.05 indicated a significant difference.

Results

We performed 272 RFA procedures in 268 complicated MC pregnancies, including 60 selective intrauterine growth restriction (sIUGR), 64 twin–twin transfusion syndrome (TTTS), 12 twin reversed arterial perfusion sequence (TRAPs), 66 foetal anomaly and 66 elective foetal reduction (EFR) cases. The overall survival rate of the co-twin was 201/272 (73.9%). The overall technical successful rate was determined at 201/263 (76.7%). The IUFD rate in the co-twin was 20/272 (7.4%). The TTTS group had recorded the lowest survival rate (37/64, 57. 8%), and the survival rate was significantly correlated with Quintero stages (P = 0.029). Moreover, the sIUGR III subgroup had a lower survival rate compared with sIUGR II (55.6%, versus 84.3%). The subgroup of foetal anomaly of gastroschisis or exomphalos had the highest IUFD rate (4/10, 40%), followed by sIUGR III (2/9, 22.2%) and dichorionic triamniotic (DCTA) subgroup (8/46, 17.9%). In EFR group, eight IUFD cases were all coming from the DCTA subgroup and received RFA before 17 weeks.

Conclusions

The perinatal outcome of RFA was correlated with the indications, with the lowest survival rate in TTTS IV and the highest IUFD incidence in abdominal wall defect followed by sIUGR III. Elective RFA after 17 weeks may prevent IUFD in DCTA pregnancies.

Monochorionic twins with selective fetal growth restriction: insight from placental whole-transcriptome analysis

BACKGROUND

The underlying pathomechanism in placenta-related selective fetal growth restriction in monochorionic diamniotic twin pregnancy is not known.

OBJECTIVE

This study aimed to investigate any differences in placental transcriptomic profile between the selectively growth-restricted twins and the normally grown cotwins in monochorionic diamniotic twin pregnancies.

STUDY DESIGN

This was a prospective study of monochorionic diamniotic twin pregnancies complicated by selective fetal growth restriction. Placental biopsy specimens were obtained from the subjects in the delivery suite. The placental transcriptome of the selectively growth-restricted twin was compared with that of the normally grown cotwin. This study was divided into 2 stages: (1) gene discovery phase in which placental tissues from 5 monochorionic diamniotic twin pregnancies complicated by selective fetal growth restriction plus 2 control twin pregnancies underwent transcriptome profiling, and transcriptome profiling was carried out using whole-genome RNA sequencing; and (2) validation phase in which placental tissues from 13 monochorionic diamniotic twin pregnancies with selective fetal growth restriction underwent RNA and protein validation. RNA and protein expression levels of candidate genes were determined using quantitative real-time polymerase chain reaction and immunohistochemistry staining.

RESULTS

A total of 1429 transcripts were differentially expressed in the placentae of selectively growth-restricted twin pairs, where 610 were up-regulated and 819 were down-regulated. Endoplasmic reticulum lectin and mannose 6-phosphate receptor were consistently differentially up-regulated in all placentae of selectively growth-restricted twins. Quantitative real-time polymerase chain reaction and immunohistochemistry staining were used to validate the results (P<.05).

CONCLUSION

The expression of endoplasmic reticulum lectin and mannose 6-phosphate receptor, which are important for angiogenesis and fetal growth, was significantly increased in the placentae of selectively growth-restricted twin of a monochorionic twin pair.

Selective fetal reduction in complicated monochorionic twin pregnancies: A comparison of techniques

OBJECTIVE

To compare perinatal outcomes associated with three methods of selective reduction in complicated monochorionic (MC) twin pregnancies: bipolar cord coagulation (BC), fetoscopic or ultrasound guided laser cord occlusion and radiofrequency ablation (RFA).

METHODS

Retrospective cohort study of complicated MC twin pregnancies undergoing selective fetal reduction at a tertiary fetal center over a 20-year period. Obstetric and perinatal outcomes were compared.

RESULTS

105 procedures met inclusion criteria: 74 RFAs, 17 lasers and 14 BCs. Procedure duration was significantly shorter for RFA (27.4 ± 15.8 minutes) compared to BC (91.7 ± 38.7 minutes) and laser (83.4 ± 40.4 minutes), P < .0001). The incidence of preterm prelabor rupture of membranes (PPROM) and co-twin demise did not differ between groups, however preterm delivery <34 weeks occurred less frequently following RFA (29.7%), compared to laser (64.7%) or BC (42.9%) (P = .02); delivery <37 weeks was also less frequent following RFA (45.9%), compared to laser (76.5%) or BC (78.6%)(P = .01). The difference in preterm birth<34 weeks between RFA and laser was maintained after adjusting for cord occlusion indication and amnionicity (OR 3.96, 95% CI 1.27-12.31).

CONCLUSIONS

In our experience, RFA procedures were simpler, faster and associated with a lower risk of preterm delivery <34 and <37 weeks, compared to laser or BC.

Reduction of multiple pregnancy: Counselling and techniques

The incidence of multiple births has risen in the last few decades. This rise is mainly due to the widespread use of assisted reproduction techniques mainly as a result of increasing maternal age at conception. Twin and higher-order multiple pregnancies are associated with increased risk of perinatal, as well as maternal, mortality and morbidity compared to singleton pregnancies. There can also be psychosocial and socioeconomic implications for women and their families. In this chapter, we aim to discuss the risks associated with multiple pregnancies, the pros and cons of fetal reduction, the current techniques used in clinical practice, and how to approach counselling parents, enabling them to make informed decisions.

Selective fetal reduction in monochorionic twins: Preliminary experience

Objective:

In complicated mono-chorionic twin pregnancies, vaso-occlusive techniques like bipolar cord coagulation (BPCC), radiofrequency ablation (RFA), interstitial laser ablation (ILA) of cord and fetoscopy guided cord coagulation with lasers are the methods proposed for selective fetal reduction. This study brings forth preliminary data of selective fetal reduction procedures at a tertiary care center in India.

Material and Methods:

This was a prospective observational study of 31 patients with complicated mono-chorionic twin pregnancies. Methods used were ILA, RFA and BPCC. Outcome measures included overall co-twin survival after selective feticide, survival rates with each method, miscarriage (defined as all fetal loss before 24 weeks), early fetal death (<24 hours after procedure) and late fetal death (>24 hours after the procedure) of co-twin.

Results:

Technical success was achieved in 30/31 (96.8%) of pregnancies. Over all take home baby rate was 63.3%. Live birth rates were 50%, 71.4% and 75% with ILA, RFA and BPCC respectively.

Conclusion:

Data from initial cases of selective fetal reduction in complicated mono-chorionic twins suggests that these procedures are feasible but are associated with high adverse perinatal outcome.

Risks in Surrogacy Considering the Embryo: From the Preimplantation to the Gestational and Neonatal Period

Surrogacy is an assisted reproduction-based approach in which the intended parents assign the gestation and birth to another woman called the surrogate mother. The drivers of surrogacy refer largely to infertility, medical conditions, same-sex couples' parenting, and cases of diversity regarding sexual identity and orientation. Surrogacy consists of a valid option for a variety of conditions or circumstances ranging from medical to social reasons. However, surrogacy may be associated with risks during the preimplantation, prenatal, and neonatal period. It became obvious during the exhaustive literature research that data on surrogacy and its association with factors specific to the IVF practice and the options available were not fully represented. Could it be that surrogacy management adds another level of complexity to the process from the ovarian stimulation, the subsequent IVF cycle, and the techniques employed within the IVF and the Genetic Laboratory to the fetal, perinatal, and neonatal period? This work emphasizes the risks associated with surrogacy with respect to the preimplantation embryo, the fetus, and the infant. Moreover, it further calls for larger studies reporting on surrogacy and comparing the surrogate management to that of the routine IVF patient in order to avoid suboptimal management of a surrogate cycle. This is of particular importance in light of the fact that the surrogate cycle may include not only the surrogate but also the egg donor, sperm donor, and the commissioning couple or single person.

Risk factors for fetal death after radiofrequency ablation for complicated monochorionic twin pregnancies

OBJECTIVE

Radiofrequency ablation (RFA) is a management alternative for complicated monochorionic twin pregnancies. The purpose of this study is to evaluate risk factors for fetal death after RFA.

METHODS

An observational study was performed to document the perinatal outcomes of all cases undergoing fetal reduction using RFA from 2010 to 2016 at the Shanghai First Maternity and Infant Hospital. A multiple regression model was built to identify predictors of the death of the remaining fetus after RFA.

RESULTS

A total of 183 patients treated with RFA for fetal reduction were analyzed, including 53 selective intrauterine growth restriction, 35 twin-twin transfusion syndrome, 36 dichorionic triamniotic triplets, 24 monochorionic twins discordant for fetal anomaly, and 35 twin reversed arterial perfusion. The prevalence of fetal death after RFA was 23% (43:183). The occurrence of fetal death after RFA was independently associated with more than 2 cycles of RFA coagulation (OR 3.46; 95% CI, 1.34-8.94; P = .01).

CONCLUSION

More than 2 cycles of RFA coagulation is the only independent risk factors of fetal death after RFA.

Outcome of Twin Pregnancies Complicated by a Neural Tube Defect

Twin pregnancies discordant for neural tube defects (NTD) is a management dilemma. Risks of preterm delivery from polyhydramnios must be balanced with the risks of selective termination (ST) of the anomalous fetus. We investigated the prevalence of twin pregnancies discordant for NTD and the rate of pregnancy complications in our institution over a 10-year period. Cases were obtained by searching the hospital ultrasound database and findings were confirmed by expert review of ultrasound images. Outcomes of ST and expectant management were assessed. Each unaffected co-twin was assigned to three consecutive twin pregnancy controls matched by chorionicity and maternal age. Primary outcome was birth before 34 weeks' gestation. Secondary outcomes were small for gestational age, mode of delivery, neonatal unit admission, and neonatal death. In total, 13 pregnancies were identified as potential cases. Of these, 11 were included in the analysis: 9 dichorionic diamniotic and 2 monochorionic diamniotic twins. Seven cases had ST and four were managed expectantly. We found 100% (4/4) of expectantly managed pregnancies delivered <34 weeks compared with 14% (1/7) of the ST group (p = .015). Polyhydramnios complicated three expectantly managed pregnancies and one pregnancy in the ST group. The birthweight SD score of all unaffected co-twins was ≥-2. The case-control analysis showed a higher rate of polyhydramnios in twin pregnancies discordant for NTD compared with controls, but little evidence for differences between groups in delivery rates <34 weeks, birthweight, neonatal unit admission, or neonatal death. ST warrants serious consideration to avoid potential complications to the unaffected co-twin.

Ethical considerations in the care of complicated twin pregnancies

Twin gestations are increasing in prevalence worldwide, and are potentially subject to medical complications which present uniquely complex ethical and psychosocial challenges for the pregnant patient and obstetrician to navigate. In this article, we explore these issues as they relate to medical decision-making in cases of discordant growth and discordant anomalies in both monochorionic and dichorionic twin pregnancies, including those affected by twin-twin transfusion syndrome, with particular attention to scenarios in which the individual fetuses hold competing interests. For each of these scenarios, we consider how decisions may positively or negatively impact one or both fetuses, and how familiarity with population outcomes, as well as sensitivity to the complex psychosocial circumstances surrounding these pregnancies, can support and inform shared decision-making.

Minimally Invasive Fetal Surgery

Fetal surgery corrects severe congenital anomalies in utero to prevent their severe consequences on fetal development. The significant risk of open fetal operations to the pregnant mother has driven innovation toward minimally invasive procedures that decrease the risks inherent to hysterotomy. In this article, we discuss the basic principles of minimally invasive fetal surgery, the general history of its development, specific conditions and procedures used to treat them, and the future of the field.

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.

Radiofrequency Ablation with an Internally Cooled Electrode for Twin Reversed Arterial Perfusion Sequence

OBJECTIVE

The study aims to evaluate the efficacy of radiofrequency ablation (RFA) with an internally cooled electrode for twin reversed arterial perfusion (TRAP) sequence.

METHODS

From April 2008 through December 2014, we retrospectively reviewed all patients who underwent RFA with an internally cooled electrode for TRAP sequence at 3 tertiary referral centers in Japan.

RESULTS

Twenty-five monochorionic diamniotic twin pregnancies underwent RFA with an internally cooled electrode for TRAP sequence at 16-27 weeks of gestation. In all cases, umbilical cord blood flow cessation in the acardiac twin was confirmed by ultrasonography with color Doppler. There were 2 cases of procedure-related complications: 1 case of unintentional septostomy and 1 case of anemia in a pump twin. Fetal demise of the pump twin occurred in 3 (12%) cases. Twenty-two (88%) of 25 pump twins were delivered alive. The median gestational age at delivery was 36 + 3 weeks (range 25 + 2-40 + 5 weeks). There were 14 cases (64%) of premature deliveries before 37 weeks and 5 (23%) before 32 weeks.

CONCLUSION

RFA with an internally cooled electrode is a feasible and effective procedure for the treatment of TRAP sequence.