Solomon technique vs selective fetoscopic laser photocoagulation for twin-twin transfusion syndrome: systematic review and meta-analysis of maternal and perinatal outcomes

What is the role of intrauterine transfusion after single intrauterine death in monochorionic twin pregnancies? Evidence from a systematic review and meta-analysis

OBJECTIVE

To investigate the role of intrauterine transfusion (IUT) in affecting the outcome of the surviving twin showing sign of fetal anemia after a single intrauterine fetal death (IUFD) in monochorionic (MC) twin pregnancies.

METHODS

PubMed, Medline and Embase databases were searched (2010-2024). The inclusion criteria were studies reporting the outcome of fetuses showing signs of fetal anemia, defined as the presence of the peak systolic velocity (PSV) of the middle cerebral artery (MCA) >1.5 MoM, after single IUFD receiving compared to those not receiving IUT. The outcomes observed were preterm birth (PTB) <34 and 28 weeks of gestation, either iatrogenic or spontaneous, co-twin intra-IUFD, co-twin neonatal death (NND), anomalies at pre- or post-natal brain imaging, abnormal neurodevelopmental outcome. Risk of bias of the included studies was assessed using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool. The GRADE methodology was used to assess the quality of the body of retrieved evidence. Random effect meta-analyses of proportions were used to analyze the data.

RESULTS

Six studies (78 twin pregnancies complicated by single IUFD showing signs of fetal anemia) were included in the systematic review. Assessment of risk of bias of observational studies according to the ROBINS-I tool is presented. Only one study reported a non-matched comparison between anemic fetuses undergoing compared to those not undergoing IUT, so we could not calculate the summary odd ratios, and we reported the results as pooled proportions. PTB occurred in 51.25% (95% CI 35.76-66.62) of cases < 34 weeks and in 17.99% (95% CI 5.84-34.91) < 28 weeks of gestation. Co-twin IUFD and NND were reported in 8.02% (95% CI 2.30-16.78) and 15.49% (95% CI 7.89-25.05), while abnormal findings at pre-or post-natal brain imaging in 20.30% (95% CI 11.61-30.69). Abnormal neurodevelopmental outcome was reported in 5.93% (95% CI 2.50-18.30).

CONCLUSION

There is a very low grade of evidence that IUT can affect the outcome of anemic fetuses after single IUFD in MC pregnancies. The findings how this systematic review, in view of the limitations of the included studies, highlighted the need for large multicenter studies sharing objective protocols of prenatal management and post-natal assessment of pregnancies complicated by single IUFD are needed to report whether IUT in the anemic fetus after single IUFD can prevent mortality and neuromorbidity.

Survival rates in pregnancies complicated by twin-to-twin transfusion syndrome undergoing laser therapy: a systematic review and meta-analysis

OBJECTIVE

Twin-to-twin transfusion syndrome (TTTS) is associated with excess perinatal mortality and morbidity. Even though Quintero staging is commonly used to assess its severity, the limitations of its prognostic value have been highlighted by researchers over the years. Recent literature indicates that fetal survival, whether for both twins or at least one, following fetoscopic laser photocoagulation of the placental anastomoses is similar in TTTS Quintero stages I and II (combined) and III and IV (combined). In this context we perform a systematic review and meta-analysis of the published literature to elucidate the survival rate of twins according to the stage of TTTS and to compare the survival rates in pregnancies complicated by stage I and II (combined) vs those with stages III and IV (combined).

DATA SOURCES

Medline, Embase, and Cochrane databases were searched.

STUDY ELIGIBILITY CRITERIA

The inclusion criteria were studies reporting the outcome of monochorionic diamniotic (MCDA) twin pregnancies with TTTS undergoing laser therapy according to the Quintero stage of the disease. The primary outcome was double survival at birth. The secondary outcomes were no survival and survival of at least one twin. All the explored outcomes were reported according to the Quintero staging system. Furthermore, we aimed to compare all the observed outcomes in pregnancies complicated by TTTS affected by stage I and II vs those with stages III and IV.

STUDY APPRAISAL AND SYNTHESIS METHODS

Random-effect meta-analyses were used to combine data, and the results reported as pooled proportions or odd ratios (OR) with their 95% confidence intervals (CI).

RESULTS

A total of 26 studies were included. Survival of both fetuses was observed in 72.9% (95% CI 68.2-77.3) of pregnancies complicated by stage I, 67.9% (95% CI 62.3-73.3) with stage II, 48.1% (95% CI 42.5-53.8) with stage III, and 53.4% (95% CI 42.5-64.3) with stage IV TTTS. At least one survivor was reported in 89.4% (95% CI 86.9-91.9) of cases with stage I, 87.1% (95% CI 82.9-90.7) with stage II, 77.3% (95% CI 71.7-82.5) with stage III, and 80.1% (95% CI 69.4-89.0) with stage 4. The corresponding figures for no survivors were 10.7% (95% CI 7.7-14.0), 11.4% (95% CI 7.8-15.6), 20.4% (95% CI 15.6-25.8), and 16.7% (95% CI 8.3-27.2), respectively. When comparing the different outcomes according to the different TTTS stages, there was no significant difference in the incidence of double survival (P=.933), at least one survivor (P=.688), and no survivors (P=.866) between stages I and II TTTS. There was also no significant difference in the incidence of double survival (P=.201), at least one survivor (P=.380), and no survivors (P=.947) between stages III and IV. Conversely, when comparing the outcome of pregnancies with stage I/II (combined) vs stages III/IV (combined), the incidence of double survival was significantly higher in pregnancies with stages I/II (OR 2.19; 95% CI 1.9-2.6, P<.001). Likewise, the incidence of at least one survivor was significantly higher (OR 1.85, 95% CI 1.5-2.6, P<.001) while that of no survivor (OR 0.56, 95% CI 0.4-0.7, P<.001) significantly lower in pregnancies with stages I/II compared to III/IV.

CONCLUSION

Perinatal survival of MCDA twin pregnancies complicated by TTTS and treated with fetoscopic laser coagulation of placental anastomoses is not significantly different between stages I and II, or between stages III and IV, apart from a higher chance of one survivor in stage III compared to stage IV. The findings from this systematic review will be useful in individualized risk assessment of twin pregnancies complicated by TTTS and tailored counseling of the parents. It also highlights the need for studies aimed at better characterizing the prenatal risk factors for mortality in pregnancies complicated by TTTS.

CONDENSATION

Perinatal survival of MCDA twin pregnancies complicated by TTTS and treated with fetoscopic laser coagulation of placental anastomoses is not significantly different between stages I and II, or between stages III and IV. El resumen está disponible en Español al final del artículo.

Update on Management and Outcomes of Monochorionic Twin Pregnancies

The management of multiple pregnancies complicated by monochorionicity continues to evolve as new investigations support a change in clinical practice to optimize outcomes. Monochorionic twins are at risk of unique conditions such as monoamnionicity, conjoined twinning, twin reversed arterial perfusion sequence, twin-twin transfusion syndrome, twin anemia-polycythemia sequence, unequal placental sharing with discordant twin growth or selective fetal growth restriction, and single-twin death that puts co-twins at risk of death or neurologic injury attributable to the shared placenta. Contemporary practice guidelines recommend serial ultrasonographic surveillance of monochorionic pregnancies to increase the early detection of problems and timely management decisions that may include increased surveillance, selective reduction or pregnancy termination, referral for in utero treatment, or earlier delivery than initially planned. Improvements in prenatal diagnosis and antenatal testing and advances in fetal therapy have contributed to more favorable outcomes in these complicated monochorionic gestations.

Placental rupture after fetoscopic SOLOMON technique for twin-twin transfusion syndrome: 2 cases report

OBJECTIVE

To present 2 cases of placental rupture at delivery after fetoscopic SOLOMON technique for twin-twin transfusion syndrome.

METHODS

2 cases diagnosed with TTTS in the second trimester. Fetoscopic SOLOMON procedure was performed successfully subsequently.

RESULTS

Placental rupture was confirmed by cesarean section in the third trimester. All fetuses were survived. No severe maternal complications but postpartum haemorrhage (PPH) was detected in one of the 2 cases.

CONCLUSION

The SOLOMON technique may further result in placental rupture which may lead to the risk of fetal demise and postpartum haemorrhage, should pay close attention.

Role of gestational age at time of placental laser surgery in outcome of twin-to-twin transfusion syndrome

OBJECTIVE

There are conflicting data on whether fetoscopic laser photocoagulation (FLP) of placental anastomoses for the treatment of twin-to-twin transfusion syndrome (TTTS) is associated with lower rates of overall survival. The objective of this study was to characterize twin survival and associated morbidity according to the gestational age at which FLP was performed.

METHODS

This was a secondary analysis of data collected prospectively on patients with a monochorionic diamniotic (MCDA) twin pregnancy who underwent FLP for TTTS at two centers between January 2011 and December 2022. Patients were divided into six groups according to gestational age at the time of FLP: < 18 weeks, 18 + 0 to 19 + 6 weeks, 20 + 0 to 21 + 6 weeks, 22 + 0 to 23 + 6 weeks, 24 + 0 to 25 + 6 weeks and ≥ 26 weeks. Demographic characteristics, sonographic characteristics of TTTS and operative characteristics were compared across the gestational age epochs. Outcomes, including overall survival, preterm delivery (PTD), preterm prelabor rupture of membranes (PPROM), intrauterine fetal demise (IUFD) and neonatal demise (NND), were also compared across gestational age epochs. Multivariate analysis was performed by fitting logistic regression models for these outcomes. Kaplan-Meier curves were constructed to compare the interval from PPROM to delivery between gestational age epochs.

RESULTS

There were 768 patients that met the inclusion criteria. The rate of dual twin survival was 61.3% for cases in which FLP was performed before 18 weeks, compared with 78.0%-86.7% when FLP was performed at ≥ 18 weeks' gestation. This appears to be driven by an increased rate of donor IUFD following FLP performed before 18 weeks (28.0%) compared with ≥ 18 weeks (9.3-14.1%). Rates of recipient IUFD and NND and donor NND were similar regardless of gestational age at FLP. The rate of PPROM was higher for FLP conducted at earlier gestational ages, ranging from 45.6% for FLP before 18 weeks to 11.9% for FLP performed at 24 + 0 to 25 + 6 weeks' gestation. However, gestational age at delivery was similar across gestational age epochs, with a median of 31.7 weeks. On multivariate analysis, donor twin loss was associated with FLP before 18 weeks, even after adjusting for selective fetal growth restriction, Quintero stage and other covariates. PPROM and PTD were also associated with FLP performed before 18 weeks after adjusting for cervical length, placental location, trocar size, laser energy and amnioinfusion.

CONCLUSIONS

FLP performed at earlier gestational ages is associated with lower overall survival, which is driven by the increased risk of donor IUFD, as opposed to differences in the rate of PPROM or PTD. Parental counseling regarding twin survival should account for the gestational age at which patients present with TTTS. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Placental architectural characteristics following laser ablation within monochorionic twins complicated by twin-twin transfusion syndrome: A systematic review and meta-analysis of outcomes

INTRODUCTION

Twin-twin transfusion syndrome (TTTS) complicates approximately 10%-15% of all monochorionic twin pregnancies. The aim of this review was to evaluate the placental architectural characteristics within TTTS twins following laser and elucidate their impact on fetal outcomes and operative success.

MATERIAL AND METHODS

Five databases were searched from inception to August 2023. Studies detailing post-delivery placental analysis within TTTS twins post-laser were included. Studies were categorized into two main groups: (1) residual anastomoses following laser and (2) abnormal cord insertion: either velamentous and/or marginal or proximate. The primary outcome was to determine the proportion of TTTS placentas with residual anastomoses and abnormal cord insertions post-laser. Secondary outcomes included assessing residual anastomoses on post-laser fetal outcomes and assessing the relationship between abnormal cord insertion and TTTS development. Study bias was critiqued using the Joanna Briggs Institute checklists and Cochrane risk of bias tool. Random-effects meta-analysis was used, and results were reported as pooled proportions or odds ratio (OR) with 95% confidence interval (CI). PROSPERO registration: CRD42023476875.

RESULTS

Twenty-six studies, comprising 4013 monochorionic twins, were included for analysis. The proportion of TTTS placentas with residual anastomoses following laser was 24% (95% CI, 0.12-0.41), with a mean and standard deviation of 4.03 ± 2.95 anastomoses per placenta. Post-laser residual anastomoses were significantly associated with intrauterine fetal death (OR, 2.38 [95% CI, 1.33-4.26]), neonatal death (OR, 3.37 [95% CI, 1.65-6.88]), recurrent TTTS (OR, 24.33 [95% CI, 6.64-89.12]), and twin anemia polycythemia sequence (OR, 13.54 [95% CI, 6.36-28.85]). Combined abnormal cord (velamentous and marginal), velamentous cord, and marginal cord insertions within one or both twins following laser were reported at rates of 49% (95% CI, 0.39-0.59), 27% (95% CI, 0.18-0.38), and 28% (95% CI, 0.21-0.36), respectively. Combined, velamentous and marginal cord insertions were not significantly associated with TTTS twins requiring laser (p = 0.72, p = 0.38, and p = 0.71, respectively) vs non-TTTS monochorionic twins.

CONCLUSIONS

To the best of our knowledge, this is the first review to conjointly explore outcomes of residual anastomoses and abnormal cord insertions within TTTS twins following laser. A large prospective study is necessitated to assess the relationship between abnormal cord insertion and residual anastomoses development post-laser.

Stage-based recipient and donor outcome in twin-to-twin transfusion syndrome treated by fetoscopic laser surgery using Solomon technique

OBJECTIVE

To evaluate twin survival stratified by Quintero stage in patients with twin-to-twin transfusion syndrome (TTTS) after Solomon laser treatment.

METHODS

This was a single-center study at Johns Hopkins Center for Fetal Therapy, investigating a cohort of consecutive twin pregnancies treated with the Solomon laser technique for TTTS. Preoperative Quintero stage, perioperative characteristics and obstetric factors were investigated in relation to neonatal survival of the recipient and donor twins at discharge. Determinants of twin survival were evaluated using univariate logistic regression and cumulative survival probability analyses.

RESULTS

Of 402 pregnancies with TTTS that underwent Solomon laser treatment, 80 (19.9%) were diagnosed with Quintero Stage-I TTTS, 126 (31.3%) with Stage II, 169 (42.0%) with Stage III and 27 (6.7%) with Stage IV. Post-laser twin anemia polycythemia sequence or recurrent TTTS occurred in 19 (4.7%) patients and 11 (2.7%) required repeat laser surgery. Preterm prelabor rupture of membranes occurred in 150 (37.3%) patients and median gestational age at delivery was 32 + 1 weeks. In 303 (75.4%) patients, both twins were alive at discharge; 67/80 (83.8%) were Stage I, 101/126 (80.2%) were Stage II, 113/169 (66.9%) were Stage III and 22/27 (81.5%) were Stage IV (P = 0.062). Donor twin survival was lower than that of recipients in cases with Stage-III TTTS (118/169 (69.8%) vs 145/169 (85.8%) (χ2 = 26.076, P < 0.0001)). Higher intertwin size discordance and absent or reversed umbilical artery (UA) end-diastolic velocity (EDV) were associated with donor demise (Nagelkerke R2, 0.38; P < 0.001). Overall, spontaneous post-laser donor demise occurred in 53 (39.6%) patients, accounting for the majority of all losses. Cumulative donor survival decreased from 92% to 65% when intertwin size discordance was >30% and to 48% when UA-EDV was absent or reversed (P < 0.001).

CONCLUSIONS

The Solomon laser technique achieves TTTS resolution and double twin survival in a high proportion of cases. Recipient and donor survival is comparable unless there is significant intertwin size discordance and placental dysfunction. This degree of unequal placental sharing, typically found in Stage-III TTTS, is the primary factor preventing double survival due to a higher rate of donor demise. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Assessing the Impact of Hematological Changes in Pregnancy on Maternal and Fetal Death: A Narrative Review

Hematological changes during pregnancy encompass a wide range of alterations in blood composition and function, including variations in hemoglobin levels, red blood cell count, and coagulation factors. These changes can be physiological or pathological and may significantly impact maternal and fetal health outcomes. This narrative review examines the relationship between various hematological changes and disorders during pregnancy and their effects on maternal and fetal mortality and morbidity. We explore conditions such as anemia, sickle cell disease, thrombophilia, and blood-borne infections like malaria, as well as the impact of multiple pregnancies on hematological parameters. The review also discusses the effects of COVID-19 on maternal hematology. Key findings include the high prevalence of adverse perinatal outcomes associated with these conditions, including early miscarriages, preterm birth, low birth weight, intrauterine growth restriction, and increased risk of maternal complications. The importance of early screening, diagnosis, and appropriate management of hematological disorders during pregnancy is emphasized. This review highlights the need for a multidisciplinary approach to managing pregnant women with hematological changes to optimize maternal and fetal outcomes.

Fetoscopic laser coagulation for twin-to-twin transfusion syndrome: a comparison of flexible 1.0/1.2 mm fetoscopes with curved sheaths of 2.7/3.3 mm2 vs. 2 mm fetoscopic lens technique with sheaths of 6.6/11.3 mm2

OBJECTIVES

Fetoscopic laser coagulation of placental anastomoses is usually performed for a treatment of twin-to-twin transfusion syndrome (TTTS). A common complication of fetoscopic laser coagulation for TTTS is preterm preliminary rupture of fetal membranes (PPROM) aggravating the neonatal outcome significantly. However, use of an flexible 1 mm fetoscope with an curved sheath could reduce iatrogenic damage of the amniotic membrane and improve neonatal outcomes after laser treatment. The aim of this study was to compare neonatal outcomes using this flexible fetoscope with curved sheath vs. use of a standard lens technique.

METHODS

Outcomes were retrospective analyzed after use of a standard lens fetoscope of 2 mm (sheath 6.63 mm2 or 11.27 mm2 for anterior placenta) and a flexible fetoscope of 1 mm or 1.2 mm (sheath 2.65 mm2 or 3.34 mm2) in two German centers of fetal surgery, performed during 2006-2019.

RESULTS

Neonatal outcome of 247 TTTS patients were analyzed including the rates of double and single fetal survival. The survival of at least one fetus was 97.2 % in the group with the ultrathin technique (n=154) compared to 88.3 % (n=93) in the group with the standard lens fetoscope (p=0.008). Survival of both fetuses was not different between groups (81.0 vs. 75.3 %). The procedure to delivery interval was significantly increased using the ultrathin fetoscope (89.1±35.0 d vs. 71.4±35.4 d, p=0.001) resulting in an increased gestational age at delivery by 11 days on average (231.9±28.1 d vs. 221.1±32.7 d, p=0.012).

CONCLUSIONS

Fetal survival can be significantly increased following TTTS using flexible fetoscope of 1 mm or 1.2 mm (sheath 2.65 mm2 or 3.34 mm2).

Intra-abdominal umbilical venous diameter and abdominal circumference discordance at 15-20 weeks' gestation: simple markers in transverse abdominal plane to predict adverse pregnancy outcomes in monochorionic diamniotic twins

PURPOSE

This study aimed to investigate the association between simple markers in fetal abdominal plane, intra-abdominal umbilical venous diameter (DIUV) and abdominal circumference (AC) discordance at 15-20 weeks' gestation, and adverse pregnancy outcomes in monochorionic diamniotic (MCDA) twins.

METHODS

We performed a retrospective analysis of MCDA twins with two live fetuses examined at 15-20 weeks from Jun 2020 to Dec 2021 at Beijing Obstetrics and Gynecology Hospital. Measurement of fetal AC and DIUV was performed according to standard protocols. Twin pregnancies with major fetal structural anomalies, chromosomal abnormalities, miscarriage, and twin reversed arterial perfusion sequence were excluded. DIUV and AC discordance in MCDA twins with an adverse pregnancy outcome was compared with a normal pregnancy outcome. Furthermore, the performance of DIUV and AC discordance in predicting adverse pregnancy outcomes in MCDA twins was assessed.

RESULTS

A total of 105 women with MCDA twin pregnancies were enrolled, contributing 179 visits. Adverse pregnancy outcomes occurred in 33.3% (35/105) of cases in our study. The intra-observer and inter-observer intraclass correlation coefficient (ICC) of both AC and DIUV were very good or excellent. There was no statistical difference in AC and DIUV discordance (%) between 15-16, 17-18, and 19-20 weeks (χ2 = 3.928, P = 0.140; χ2 = 2.840, P = 0.242). Both AC and DIUV discordance were greater in twins with adverse pregnancy outcomes than that in twins with normal pregnancy outcome at each pregnancy periods. Both AC discordance (OR 1.2, 95% CI 1.1-1.3) and DIUV discordance (OR 1.2, 95% CI 1.1-1.2) were associated with adverse pregnancy outcomes. The AUC for predicting adverse pregnancy outcomes by AC discordance was 0.75 (95% CI 0.68-0.83), with a sensitivity of 58.7% (95% CI 51.9-64.5) and a specificity of 86.2% (95% CI 81.7-88.4). The AUC for predicting adverse pregnancy outcomes by DIUV was 0.78 (95% CI 0.70-0.86), with sensitivity and specificity of 65.1% (95% CI 58.1-70.3) and 86.2% (95% CI 81.7-88.4), respectively.

CONCLUSIONS

The AC discordance and DIUV discordance could predict adverse pregnancy outcomes in MCDA twins. When these simple markers occurred, intensive surveillance was recommended.

Management of short cervix in twin-to-twin transfusion syndrome: a role for pessary placement following fetoscopic laser surgery?

BACKGROUND

Preterm labor and delivery is a major concern for patients with twin-to-twin transfusion syndrome undergoing fetoscopic laser surgery. A preoperative short cervix is a risk factor for preterm labor. Pessary placement is a short-acting intervention that may be useful to reduce this adverse event.

OBJECTIVE

This study aimed to investigate the relationship between pessary placement and preterm delivery in monochorionic twin pregnancies with twin-to-twin transfusion syndrome and a short cervix before fetoscopic laser surgery.

STUDY DESIGN

This was a retrospective study in 2 centers, including all pregnancies affected by twin-to-twin transfusion syndrome that underwent fetoscopic laser surgery with the Solomon technique between 2013 and 2022 (center A) and 2014 and 2022 (center B) with a preoperative cervical length below 25 mm. This study explored the correlation between cervical length and fetoscopic laser surgery-to-delivery interval following active or expectant management and compared perinatal outcomes between patients managed expectantly and patients managed with pessary placement, using multivariate analysis to control for potential confounders. Patients with a cervical length below 5 mm were not included in the comparative analysis.

RESULTS

Of 685 patients, 134 met the inclusion criteria. Moreover, 21 patients were treated with a cervical cerclage and excluded from the analysis, leaving 113 patients for the final analysis. There was a significant negative correlation between cervical length at fetoscopic laser surgery and the risk of early delivery (adjusted odds ratio, 0.66; 95% confidence interval, 0.49-0.81; P<.001). The use of a pessary correlated with fewer patients delivering before 28 weeks of gestation (adjusted odds ratio, 0.28; 95% confidence interval, 0.09-0.75), fewer double neonatal demise (adjusted odds ratio, 0.2; 95% confidence interval, 0.05-0.75). Posthoc subgroup analysis suggested that these improvements were essentially noticeable for cervical lengths between 5 and 18 mm, where pessary placement was associated with an increased fetoscopic laser surgery-to-delivery interval (+24 days; 95% confidence interval, 0.86-42; P=.042) and later gestational age at delivery (+3.3 weeks; 95% confidence interval, 0.86-42; P=.035).

CONCLUSION

Patients with a moderately shortened cervix, between 5 and 18 mm, may benefit from pessary placement after fetoscopic surgery for twin-to-twin transfusion syndrome, resulting in a reduction of adverse neonatal outcomes, double neonatal demise, and severe preterm delivery.

Monochorionic Twins: TTTS, TAPS, and Selective Fetal Growth Restriction

With an increasing incidence of twin gestations, understanding the inherent risks associated with these pregnancies is essential in modern obstetrics. The unique differences in placentation in monochorionic twins leads to unique complications, including twin-to-twin transfusion syndrome, the twin anemia-polycythemia sequence, and selective fetal growth restriction. Not only does the understanding of the monochorionic placenta lead to an understanding of the pathophysiology of the complications of monochorionic twins, but it also has led to the development of highly effective directed fetal therapy via fetoscopic laser coagulation used in twin-to-twin transfusion syndrome.

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.

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

OBJECTIF

Cette directive clinique passe en revue les données probantes sur la prise en charge de la grossesse gémellaire monochoriale normale et compliquée.

POPULATION CIBLE

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

Guideline No. 440: Management of Monochorionic Twin Pregnancies

OBJECTIVE

This guideline reviews the evidence-based management of normal and complicated monochorionic twin pregnancies.

TARGET POPULATION

Women with monochorionic twin or higher order multiple pregnancies.

BENEFITS, HARMS, AND COSTS

Implementation of these recommendations should improve the management of both complicated and uncomplicated monochorionic (and higher order multiple) twin pregnancies. They will help users monitor monochorionic twin pregnancies appropriately and identify and manage monochorionic twin complications optimally in a timely manner, thereby reducing perinatal morbidity and mortality. These recommendations entail more frequent ultrasound monitoring of monochorionic twins compared to dichorionic twins.

EVIDENCE

Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate MeSH headings (Twins, Monozygotic; Ultrasonography, Prenatal; Placenta; Fetofetal Transfusion; Fetal Death; Fetal Growth Retardation). Results were restricted to systematic reviews, randomized controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the principal authors. The Board of the SOGC approved the final draft for publication. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

Maternal-fetal medicine specialists, obstetricians, radiologists, sonographers, family physicians, nurses, midwives, residents, and other health care providers who care for women with monochorionic twin or higher order multiple pregnancies.

TWEETABLE ABSTRACT

Canadian (SOGC) guidelines for the diagnosis, ultrasound surveillance and management of monochorionic twin pregnancy complications, including TTTS, TAPS, sFGR (sIUGR), acardiac (TRAP), monoamniotic twins and intrauterine death of one MC twin.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Two Year Neurodevelopmental Outcome after Fetoscopic Laser Therapy for Twin-Twin Transfusion Syndrome: Comparison with Uncomplicated Monochorionic Diamniotic Twins

BACKGROUND

Twin-twin Transfusion Syndrome (TTTS) represents a significant complication in monochorionic twin pregnancies, caused by an unbalanced shunting of blood through intertwin placental vascular anastomoses. Despite advances in fetoscopic laser surgery, TTTS is still associated with a high rate of cerebral injury. However, there are no studies comparing these pregnancies with uncomplicated monochorionic diamniotic (MCDA) twin pregnancies, establishing the baseline risk of neurodevelopmental impairment. The aim of this study is to evaluate the odds of neurodevelopmental impairment in MCDA twins who undergo fetoscopic laser surgery for twin-twin transfusion syndrome, in comparison to a cohort of uncomplicated MCDA twin pregnancies.

STUDY DESIGN

This is a retrospective cohort study of children born from MCDA twin pregnancies at a single center between 2008 and 2019. A routine, standardized follow-up assessment was conducted at a minimum of 2 years after delivery. The primary outcome of this was a 2 year neurodevelopmental impairment. Neurological, motor, and cognitive development was assessed by using the revised Brunet-Lézine scale.

RESULTS

176 children met the enrolment criteria. Of these, 42 (24%; TTTS group) underwent fetoscopic laser surgery for TTTS during pregnancy, and 134 (76%; uncomplicated MCDA group) were uncomplicated MCDA pregnancies. The primary outcome was found in four children (9.52%) in the TTTS group and ten children (7.46%) in the uncomplicated MCDA group (p = 0.67, aOR 2.82, 95% CI 0.49-16.23). Major neurologic impairment was found in 2.38% after fetoscopic laser surgery and 1.49% in uncomplicated MCDA twins (p = 0.70, aOR 0.97, 95% CI 0.22-4.24). The data were adjusted by birth order, birth weight, and gestational age at birth.

CONCLUSIONS

The outcome in MCDA twins who underwent fetoscopic laser surgery for TTTS is comparable to the outcome in uncomplicated MCDA twins. Our findings emphasize the need for long-term neurodevelopmental follow-ups in all children from monochorionic twin gestations.