Late selective termination in dichorionic twins: comparing late second and third trimester procedures.

RESEARCH QUESTION: Do perinatal outcomes of selective termination performed in the late second versus third trimester differ and what risk factors are associated with subsequent preterm birth? DESIGN: This is a retrospective cohort study of late selective terminations performed in dichorionic twins between 2009 and 2021. Perinatal outcomes were compared between two groups: group A, late second trimester (20.2 to 24.2 weeks, n = 26), and group B, third trimester (≥28.2 weeks, n = 55) selective terminations. Univariate and multivariate analyses were conducted to identify factors associated with post-procedure preterm birth. RESULTS: In total, 81 dichorionic twin pregnancies were included. There were no pregnancy losses but 16% (13/81) of cases experienced complications. Group A had a higher median birthweight centile (36.5th versus 15th centile, P = 0.002) and lower rates of intrauterine growth restriction (IUGR) and Caesarean delivery (11.5% versus 32.7%, P = 0.04; and 26.9% versus 61.8%, P = 0.003) than group B. Preterm birth rates were similar (46.2% versus 63.6%, P = 0.15). Multiple regression revealed that reduction of the presenting twin and cervical length ≤35 mm were independently associated with post-procedure preterm birth (odds ratio [OR] 8.7, P = 0.001, 95% confidence interval [CI] 2.5-29.8; OR 3.8, P = 0.015, 95% CI 1.3-11). CONCLUSIONS: Late second trimester selective termination is associated with a higher birthweight centile and lower rates of IUGR and Caesarean delivery, compared with third trimester selective termination. Cervical length 35 mm or less and reduction of the presenting twin are independent risk factors for post-procedural preterm birth. These findings may help determine the optimal time to perform a late selective termination.

Perinatal outcomes of selective termination in dichorionic twin pregnancies: a retrospective study from a single center.

OBJECTIVE: Selective termination (ST) is an appropriate procedure for managing discordant fetal anomalies in dichorionic diamniotic (DCDA) twin pregnancies. The aim of this study was to investigate the perinatal outcomes of ST at different gestational ages in DCDA twin pregnancies. METHODS: This retrospective study was conducted on DCDA twin pregnancies with STs at West China Second University Hospital between January 2012 and December 2022. According to the gestational age at which ST was performed, the patients were assigned to four groups: Group 1 (13 to 17 + 6 weeks), Group 2 (18 to 23 + 6 weeks), Group 3 (24 to 27 + 6 weeks), and Group 4 (≥ 28 weeks). RESULTS: We identified 230 patients for this study. The overall rates of miscarriage, preterm delivery at < 32 weeks, and term delivery were 1.3%, 10.5%, and 50%, respectively, while the rates of live birth and neonatal survival were 98.7% and 98.2%, respectively. The rate of term birth was highest (70.6%) and the birth weight was heaviest (2931 ± 535 g) in Group 1 (p = 0.000). In the presence of a fetus subjected to feticide, the mean delivery age was earlier than that in the non-presenting group (p = 0.017); accordingly, the mean birth weight in the feticide group was lower (2366 ± 628 g) than that in the non-presenting group (2590 ± 634 g) (p = 0.011). When we examined the relative relationship between reduction weeks and delivery weeks of twins by correlation analysis, we observed that with regard to maternal prognosis, two pregnancies involved preterm premature rupture of membranes (PPROM) at 7 days and 3 days after the procedure. Intrauterine infection occurred in two patients in Group 4, but there were no maternal deaths or maternal coagulatory abnormalities. CONCLUSIONS: Optimal perinatal outcomes were obtained by ST of DCDA pregnancies before 18 weeks, regardless of whether or not the reduced fetus was the presenting twin. However, if legally possible, late (i.e., after 28 weeks) procedures can be a safe alternative for patients diagnosed after the 18th week of gestation. Overall, we herein noted a negative correlation between the procedure week and the delivery week in this study. Moreover, ST of the non-presenting twin was associated with a heavier birth weight and later gestational age at delivery.

Risks and pregnancy outcome after fetal reduction in dichorionic twin pregnancies: a Danish national retrospective cohort study.

BACKGROUND: Twin pregnancies carry a higher risk of congenital and structural malformations, and pregnancy complications including miscarriage, stillbirth, and intrauterine fetal death, compared with singleton pregnancies. Carrying a fetus with severe malformations or abnormal karyotype places the remaining healthy fetus at an even higher risk of adverse outcome and pregnancy complications. Maternal medical conditions or complicated obstetrical history could, in combination with twin pregnancy, cause increased risks for both the woman and the fetuses. To our knowledge, no previous studies have evaluated and compared the outcomes of all dichorionic twin pregnancies and compared the results of reduced twins with those of nonreduced and primary singletons in a national cohort. These data are important for clinicians when counseling couples about fetal reduction and its implications. OBJECTIVE: This study aimed to describe and compare the risks of adverse pregnancy outcomes, including the risk of pregnancy loss, in a national cohort of all dichorionic twins-reduced, nonreduced, and primary singletons. In addition, we examined the implications of gestational age at fetal reduction on gestational age at delivery. STUDY DESIGN: This was a retrospective cohort study of all Danish dichorionic twin pregnancies, including pregnancies undergoing fetal reduction and a large proportion of randomly selected primary singleton pregnancies with due dates between January 2008 and December 2018. The primary outcome measures were adverse pregnancy outcomes (defined as miscarriage before 24 weeks, stillbirth from 24 weeks, or single intrauterine fetal death in nonreduced twin pregnancies), preterm delivery, and obstetrical pregnancy complications. Outcomes after fetal reduction were compared with those of nonreduced dichorionic twins and primary singletons. RESULTS: In total, 9735 dichorionic twin pregnancies were included, of which 172 (1.8%) were reduced. In addition, 16,465 primary singletons were included. Fetal reductions were performed between 11 and 23 weeks by transabdominal needle-guided injection of potassium chloride, and outcome data were complete for all cases. Adverse pregnancy outcome was observed in 4.1% (95% confidence interval, 1.7%-8.2%) of reduced twin pregnancies, and 2.4% (95% confidence interval, 0.7%-6.1%) were delivered before 28 weeks, and 4.2% (95% confidence interval, 1.7%-8.5%) before 32 weeks. However, when fetal reduction was performed before 14 weeks, adverse pregnancy outcomes occurred in only 1.4% (95% confidence interval, 0.0%-7.4%), and delivery before 28 and 32 weeks diminished to 0% (95% confidence interval, 0.0%-5.0%) and 2.8% (95% confidence interval, 0.3%-9.7%), respectively. In contrast, 3.0% (95% confidence interval, 2.7%-3.4%) of nonreduced dichorionic twins had an adverse pregnancy outcome, and 1.9% (95% confidence interval, 1.7%-2.1%) were delivered before 28 weeks, and 7.3% (95% confidence interval, 6.9%-7.7%) before 32 weeks. Adverse pregnancy outcomes occurred in 0.9% (95% confidence interval, 0.7%-1.0%) of primary singletons, and 0.2% (95% confidence interval, 0.1%-0.3%) were delivered before 28 weeks, and 0.7% (95% confidence interval, 0.6%-0.9%) before 32 weeks. For reduced twins, after taking account of maternal factors and medical history, it was demonstrated that the later the fetal reduction was performed, the earlier the delivery occurred (P<.01). The overall risk of pregnancy complications was significantly lower among reduced twin pregnancies than among nonreduced dichorionic twin pregnancies (P=.02). CONCLUSION: In a national 11-year cohort including all dichorionic twin pregnancies, transabdominal fetal reduction by needle guide for fetal or maternal indication was shown to be safe, with good outcomes for the remaining co-twin. Results were best when the procedure was performed before 14 weeks.

Triple trouble: uncovering the risks and benefits of early fetal reduction in trichorionic triplets in a large national Danish cohort study.

BACKGROUND: Triplet pregnancies are high risk for both the mother and the infants. The risks for infants include premature birth, low birthweight, and neonatal complications. Therefore, the management of triplet pregnancies involves close monitoring and may include interventions, such as fetal reduction, to prolong the pregnancy and improve outcomes. However, the evidence of benefits and risks associated with fetal reduction is inconsistent. OBJECTIVE: This study aimed to compare the outcomes of trichorionic triplet pregnancies with and without fetal reduction and with nonreduced dichorionic twin pregnancies and primary singleton pregnancies. STUDY DESIGN: All trichorionic triplet pregnancies in Denmark, including those with fetal reduction, were identified between 2008 and 2018. In Denmark, all couples expecting triplets are informed about and offered fetal reduction. Pregnancies with viable fetuses at the first-trimester ultrasound scan and pregnancies not terminated were included. Adverse pregnancy outcome was defined as a composite of miscarriage before 24 weeks of gestation, stillbirth at 24 weeks of gestation, or intrauterine fetal death of 1 or 2 fetuses. RESULTS: The study cohort was composed of 317 trichorionic triplet pregnancies, of which 70.0% of pregnancies underwent fetal reduction to a twin pregnancy, 2.2% of pregnancies were reduced to singleton pregnancies, and 27.8% of pregnancies were not reduced. Nonreduced triplet pregnancies had high risks of adverse pregnancy outcomes (28.4%), which was significantly lower in triplets reduced to twins (9.0%; difference, 19.4%, 95% confidence interval, 8.5%-30.3%). Severe preterm deliveries were significantly higher in nonreduced triplet pregnancies (27.9%) than triplet pregnancies reduced to twin pregnancies (13.1%; difference, 14.9%, 95% confidence interval, 7.9%-21.9%). However, triplet pregnancies reduced to twin pregnancies had an insignificantly higher risk of miscarriage (6.8%) than nonreduced twin pregnancies (1.1%; difference, 5.6%; 95% confidence interval, 0.9%-10.4%). CONCLUSION: Triplet pregnancies reduced to twin pregnancies had significantly lower risks of adverse pregnancy outcomes, severe preterm deliveries, and low birthweight than nonreduced triplet pregnancies. However, triplet pregnancies reduced to twin pregnancies were potentially associated with a 5.6% increased risk of miscarriage.

Adverse outcome following selective termination of presenting twin vs non-presenting twin.

OBJECTIVE: Data are lacking on the impact on pregnancy outcome of the position of the abnormal fetus in a discordant twin pregnancy undergoing selective termination (ST). Tissue maceration post ST of the presenting twin may lead to early rupture of membranes, amnionitis and preterm labor. The aim of this study was to evaluate pregnancy complications and outcome following ST of the presenting vs non-presenting twin. METHODS: This was a multicenter retrospective cohort study of dichorionic diamniotic twin pregnancies that underwent ST due to a discordant fetal anomaly (structural or genetic) between 2007 and 2021. The study population was divided into two groups according to the position of the reduced twin (presenting or non-presenting) and outcomes were studied accordingly. The primary outcome was a composite of early complications following ST, including infection, preterm prelabor rupture of membranes and pregnancy loss. RESULTS: A total of 190 dichorionic twin pregnancies were included, of which 73 underwent ST of the presenting twin and 117 of the non-presenting twin. The groups did not differ in either baseline demographic characteristics or mean gestational age at the time of the procedure. ST of the presenting twin resulted in a significantly higher rate of early complications compared with the non-presenting twin (19.2% vs 7.7%; P = 0.018). Moreover, the rates of preterm delivery (75.3% vs 37.6%; P < 0.001) and neonatal intensive care unit admission (45.3% vs 17.1%; P < 0.001) were higher, and birth weight was lower (P < 0.001), in those pregnancies in which the presenting twin was reduced. CONCLUSIONS: ST of the presenting twin resulted in a higher rate of adverse pregnancy outcome compared with that of the non-presenting twin. These findings should be acknowledged during patient counseling and, if legislation permits, taken into consideration when planning ST. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Optimal timing of fetal reduction from twins to singleton: earlier the better or later the better?

OBJECTIVES: To determine the rate of pregnancy complications and adverse obstetric and neonatal outcomes of twin pregnancies that were reduced to singleton at an early compared with a later gestational age. METHODS: This was a historical cohort study of dichorionic diamniotic twin pregnancies that underwent fetal reduction to singletons in a single tertiary referral center between January 2005 and February 2017. The study population was divided into two groups according to gestational age at fetal reduction: those performed at 11-14 weeks' gestation, mainly at the patient's request or as a result of a complicated medical or obstetric history; and selective reductions performed at 15-23 weeks for structural or genetic anomalies. The main outcome measures compared between pregnancies that underwent early reduction and those that underwent late reduction included rates of pregnancy complications, pregnancy loss, preterm delivery and adverse neonatal outcome. RESULTS: In total, 248 dichorionic diamniotic twin pregnancies were included, of which 172 underwent early reduction and 76 underwent late reduction. Although gestational age at delivery was not significantly different between the late- and early-reduction groups (38 weeks, (interquartile range (IQR), 36-40 weeks) vs 39 weeks (IQR, 38-40 weeks); P = 0.2), the rates of preterm delivery < 37 weeks (28.0% vs 14.0%; P = 0.01), < 34 weeks (12.0% vs 1.8%; P = 0.002) and < 32 weeks (8.0% vs 1.8%; P = 0.026) were significantly higher in pregnancies that underwent late reduction. Regression analysis revealed that late reduction of twins was an independent risk factor for preterm delivery, after adjustment for maternal age, parity, body mass index and the location of the reduced sac. Rates of early complications linked to the reduction procedure itself, such as infection, vaginal bleeding and leakage of fluids, were comparable between the groups (7.0% for early reduction vs 9.2% for late reduction; P = 0.53). There was no significant difference in the rate of pregnancy loss before 24 weeks (0.6% for early reduction vs 1.3% for late reduction; P = 0.52), and no cases of intrauterine fetal death at or after 24 weeks were documented. There was no significant difference in the prevalence of gestational diabetes mellitus, hypertensive disorders of pregnancy, preterm prelabor rupture of membranes or small-for-gestational age. The rates of respiratory distress syndrome (6.7% vs 0%; P = 0.002), need for mechanical ventilation (6.7% vs 0.6%; P = 0.01) and composite neonatal morbidity (defined as one or more of respiratory distress syndrome, sepsis, necrotizing enterocolitis, intraventricular hemorrhage, need for respiratory support or neonatal death) (10.7% vs 2.9%; P = 0.025) were higher in the late- than in the early-reduction group. Other neonatal outcomes were comparable between the groups. CONCLUSIONS: Compared with late first-trimester reduction of twins, second-trimester reduction is associated with an increased rate of prematurity and adverse neonatal outcome, without increasing the rate of procedure-related complications. Technological advances in sonographic diagnosis and more frequent use of chorionic villus sampling have enabled earlier detection of fetal anatomic and chromosomal abnormalities. Therefore, efforts should be made to complete early fetal assessment to allow reduction during the first trimester. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Conjoined twins in dichorionic diamniotic triplet pregnancy: a report of three cases and literature review.

BACKGROUND: Conjoined twins are a rare and serious complication of monochorionic twins. The total incidence is 1.5 per 100,000 births, and about 50% are liveborn. Prenatal screening and diagnosis of conjoined twins is usually performed by ultrasonography. Magnetic resonance imaging can be used to assist in the diagnosis if necessary. Conjoined twins in dichorionic diamniotic triplet pregnancy are extremely rare. CASE PRESENTATION: We reported three cases of dichorionic diamniotic triplet pregnancy with conjoined twins. Due to the poor prognosis of conjoined twins evaluated by multidisciplinary teams, selective termination of conjoined twins was performed in three cases. In case 1, selective reduction of the conjoined twins was performed at 16 gestational weeks, and a healthy female baby weighing 3270 g was delivered at 37 weeks. In case 2, the conjoined twins were selectively terminated at 17 weeks of gestation, and a healthy female baby weighing 2760 g was delivered at 37 weeks and 4 days. In case 3, the conjoined twins were selectively terminated at 15 weeks and 2 days, and a healthy female baby weighing 2450 g was delivered at 33 weeks and 6 days. The babies of all three cases were followed up and are in good health. CONCLUSION(S): Surgical separation is the only treatment for conjoined twins after birth. Early determination of chorionicity and antenatal diagnosis of conjoined twins in triplet gestations are critical for individualized management options and the prognosis of normal triplets. Expecting parents should be extensively counseled by multidisciplinary teams. If there are limitations in successful separation after birth, early selective termination of the conjoined twins by intrathoracic injection of potassium chloride may be a procedure in dichorionic diamniotic triplet pregnancy to improve perinatal outcomes of the normal triplet.

Perinatal outcome after selective termination in dichorionic twins discordant for congenital anomalies.

INTRODUCTION: Our objective was to evaluate the perinatal outcome of selective termination of dichorionic twin pregnancies with discordant anomalies, according to gestational age at time of procedure. MATERIAL AND METHODS: Retrospective review of 147 dichorionic twin pregnancies referred to our Fetal Medicine Unit between 2003 and 2018 for selective termination. Gestational age at delivery, fetal loss, and overall and 28-day post-delivery survival rates, were evaluated according to gestational age at time of procedure. Selective termination procedure was defined as early, intermediate, and late when performed before 18 weeks, between 18 and 23 weeks, and after 23 weeks, respectively. Kruskal-Wallis and chi-squared test were used to compare groups. RESULTS: Overall survival at 28 days post-delivery, pregnancy loss, and preterm delivery before 32 weeks of gestation rates were 93.4%, 6.9%, and 15.5%, respectively. When stratified by gestational age at procedure, intermediate selective termination was associated with a lower survival rate than early and late procedures (86% vs. 96.9% and 100%, respectively; p = 0.035), and a nonsignificant trend for higher pregnancy loss (12% vs. 3.1%). Preterm delivery before 32 weeks of gestation occurred in 27% of late procedures, which was significantly higher than in early (9.5%) and intermediate (18.2%) procedures. CONCLUSIONS: Selective termination in dichorionic twin pregnancies with discordant fetal anomaly is associated with low pregnancy loss and preterm delivery rate, primarily when performed before 18 weeks. When legally possible, late procedures can be a good alternative, particularly in those cases diagnosed beyond the 18th week of gestation.

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.

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

INTRODUCTION: Twin reversed arterial perfusion (TRAP) sequence is a phenomenon seen in 1-3% of monochorionic twin pregnancies, where the acardiac fetus is found to have multiple anomalies. The normal pump twin maintains its own perfusion in addition to that of its acardiac co-twin. As a result, if the acardiac twin increases in size, the burden on the pump twin is increased, leading to cardiac failure, hydrops fetalis, polyhydramnios, premature delivery, and perinatal death. The outcome of pregnancy is largely dependent on the growth of the acardiac twin. In view of high perinatal loss, surgical techniques to interrupt the blood flow to the acardiac twin have been evaluated. METHODS: We evaluated interstitial laser therapy, which is the main mode of therapy in our unit, of TRAP pregnancies referred over a 5-year period. Interstitial laser was offered if the blood flow in the acardiac twin was found to be persistent at 2 consecutive examinations or if there were cardiac or hydropic changes in the pump twin at the first examination. RESULTS: A total of 18 cases of TRAP were referred during this period and all were counselled regarding fetal therapy if the situation were to deteriorate; 5 couples (27.7%) opted for termination of pregnancy; of the remaining 13, 7 (53.8%) agreed to perform intervention following confirmation of a normal karyotype. Six (85.7%) and 1 (14.3%) lasers were performed in the second and third trimesters, respectively; all 7 had a normal outcome of the pump twin. There were 6/13 (46.2%) in the expectant group who continued the pregnancy with no intervention, with 2 term live births (33.3%). CONCLUSIONS: Our study confirms that there is a high risk of spontaneous loss in untreated pregnancies with TRAP, primarily due to polyhydramnios and fetal hydrops. In the pregnancies that underwent interstitial laser, there was a more favourable outcome. Interstitial laser is minimally invasive, safe, and feasible in experienced hands.

Fatal Umbilical Cord Strangulation in the Remaining Co-Twin after Selective Foeticide with Radiofrequency Ablation for Twin-Twin Transfusion Syndrome.

We report a case of a monochorionic diamniotic twin diagnosed with twin-twin transfusion syndrome (TTTS; stage 3) with co-existing severe cerebral damage in the donor twin at 18 + 4 weeks' gestation. After counselling, the parents opted for selective foeticide of the donor twin. For the procedure, radiofrequency ablation (RFA) was used. Serial ultrasound examinations at 20 + 1 and 21 + 1 weeks' gestation showed good recovery of the ex-recipient, after which the patient was sent back to the referring hospital. At 29 + 5 weeks' gestation, an unexpected foetal death was diagnosed. On macroscopic placental examination, (iatrogenic) monoamnionicity was detected. In addition, the umbilical cord of the recipient was found to be constricted by the macerated umbilical cord of the ex-donor. This case demonstrates that iatrogenic monoamnionicity can be a serious complication of RFA in monochorionic twins complicated by TTTS, with a subsequent risk for cord entanglement leading to a fatal outcome for the remaining co-twin. Although the actual incidence of iatrogenic monoamnionicity after RFA remains unknown, increased attention to the intactness of the inter-twin membrane even weeks after the RFA may be required.

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.

Umbilical Cord Occlusion via Laser Coagulation in Monochorionic Multifetal Gestations before and after 20 Weeks of Gestation.

INTRODUCTION: Umbilical cord occlusion (UCO) utilizing laser photocoagulation is often not considered an option for selective termination after 20 weeks of gestation due to reported limitations of the procedure because of umbilical cord size. We compared outcomes after laser umbilical cord occlusion (L-UCO) before and after 20 weeks of gestation. MATERIALS AND METHODS: We examined all patients with monochorionic- diamniotic twins and higher-order multiples (monoamniotic excluded) that underwent L-UCO at our facility between 2006 and 2014. Statistical analysis was performed using Fisher's exact and Kruskal-Wallis tests as appropriate. RESULTS: Of 43 L-UCO cases, 11 cases (25.6%) had a discordant anomaly, and 32 cases (74.4%) had twin reversed arterial perfusion (TRAP) sequence. We achieved complete vascular occlusion in 100% (43/43) of cases of attempted L-UCO. There were 22 cases (51.2%) with gestational age ≤20 weeks, and 21 cases (48.8%) with gestational age >20 weeks. Perioperative patient characteristics and outcomes did not differ between the two groups. Survival rates were 90.9% (20/22) and 100% (21/21) at ≤20 weeks of gestation and >20 weeks of gestation, respectively. DISCUSSION: The results of this study suggest that L-UCO is a reasonable surgical modality for patients prior to and beyond 20 weeks of gestation.

Dichorionic triplet pregnancies: risk of miscarriage and severe preterm delivery with fetal reduction versus expectant management. Outcomes of a cohort study and systematic review.

BACKGROUND: In trichorionic pregnancies, fetal reduction from three to two lowers the risk of severe preterm delivery, but provides no advantage in survival. Similar data for dichorionic triamniotic (DCTA) triplets is not readily available. OBJECTIVES: To document the natural history of DCTA triplets and the effect of reduction on the risk of miscarriage and severe preterm delivery, compared with expectant management. SEARCH STRATEGY: Systematic search on MEDLINE, EMBASE, and the Cochrane Library. SELECTION CRITERIA: DCTA triplets with three live fetuses at 8-14 weeks of gestation, outcome data with expectant management and/or reduction, miscarriage before 24 weeks of gestation and/or severe preterm delivery before 32-33 weeks of gestation. DATA COLLECTION AND ANALYSIS: Five studies were included. Data from these were combined with data from three centres. MAIN RESULTS: There were 331 DCTA triplets. The miscarriage rate was 8.9% (95% CI 5.8-13.3%) and the severe preterm delivery rate was 33.3% (95% CI 27.5-39.7%), with expectant management. The miscarriage rate was 14.5% (95% CI 7.6-26.2%) with a reduction of the monochorionic pair, 8.8% (95% CI 3.0-23.0%) with a reduction of one fetus of the monochorionic pair, and 23.5% (9.6-47.3%) with a reduction of the fetus with a separate placenta. Severe preterm delivery rates were 5.5% (95% CI 1.9-14-9%), 11.8% (95% CI 4.7-26.6%), and 17.6% (95% CI 6.2-41.0%), respectively. CONCLUSIONS: In DCTA triplets, expectant management is a reasonable choice when the top priority is a liveborn infant. Where the priority is to minimise severe preterm delivery, the most advisable option is fetal reduction. Further studies are needed to clarify which particular technique is advisable to optimise the outcome.

Perinatal outcomes between immediate vs deferred selective termination in dichorionic twin pregnancies with fetal congenital anomalies: a French multicenter study.

BACKGROUND: Because selective termination for discordant dichorionic twin anomalies carries a risk of pregnancy loss, deferring the procedure until the third trimester can be considered in settings where it is legal. OBJECTIVE: To determine whether perinatal outcomes were more favorable following deferred rather than immediate selective termination. STUDY DESIGN: A French multicenter retrospective study from 2012 to 2023 on dichorionic twin pregnancies with selective termination for fetal conditions, which were diagnosed before 24 weeks gestation. Pregnancies with additional risk factors for late miscarriage were excluded. We defined 2 groups according to the intention to perform selective termination within 2 weeks after the diagnosis of the severe fetal anomaly was established (immediate selective termination) or to wait until the third trimester (deferred selective termination). The primary outcome was perinatal survival at 28 days of life. Secondary outcomes were pregnancy losses before 24 weeks gestation and preterm delivery. RESULTS: Of 390 pregnancies, 258 were in the immediate selective termination group and 132 in the deferred selective termination group. Baseline characteristics were similar in both groups. Overall survival of the healthy co-twin was 93.8% (242/258) in the immediate selective termination group vs 100% (132/132) in the deferred selective termination group (P<.01). Preterm birth <37 weeks gestation was lower in the immediate than in the deferred selective termination group (66.7% vs 20.2%; P<.01); preterm birth <28 weeks gestation and <32 weeks gestation did not differ significantly (respectively 1.7% vs 0.8%; P=.66 and 8.26% vs 11.4%; P=.36). In the deferred selective termination group, an emergency procedure was performed in 11.3% (15/132) because of threatened preterm labor, of which 3.7% (5/132) for imminent delivery. CONCLUSION: Overall survival after selective termination was high regardless of the gestational age at which the procedure was performed. Postponing selective termination until the third trimester seems to improve survival, whereas immediate selective termination reduces the risk of preterm delivery. Furthermore, deferred selective termination requires an expert center capable of performing the selective termination procedure on an emergency basis if required.

Left Ventricular Outflow Occlusion: An Alternative Approach to Late Selective Fetal Termination in Monochorionic Twin Gestations.

We report the case of a monochorionic twin gestation discordant for a mutation in the chromodomain-helicase-DNA-binding protein 7 (CHD7) gene and cerebral abnormalities consequent to an early devastating cerebrovascular event. The parents elected for selective termination given the poor prognosis for this fetus, but given socio-economic considerations wished to defer this procedure as late in gestation as possible, despite awareness of the risks and limitations of existing techniques at the end of pregnancy.  A novel technique was used to achieve selective feticide in the late-preterm period. An endovascular balloon catheter was used to occlude the left ventricular outflow and coronary circulations resulting in fetal asystole while also arresting fetoplacental flow in this fetus, immediately prior to the delivery of the healthy fetus.

[Monochorionic biamniotic twin pregnancies outcomes in Reunion Island with indication of in utero transfert]. / Prise en charge des grossesses monochoriales biamniotiques réunionnaises avec indication de transfert in utero.

OBJECTIVE: Complicated monochorionic biamniotic (MCBA) twin pregnancies may require treatment with fetoscopic laser photocoagulation, in case of Twin Oligo-Polyhydramnios Sequence or need of a selective termination of pregnancy. Patients requiring these treatments would need medical transfer to Metropolitan France because these are unavailable in Réunion Island. We evaluated the outcomes of MCBA pregnancies in Reunion Island with indications for fetoscopy, with a view to discussing the interest of training doctors on the Reunion Island, to practice fetoscopy on site. MATERIALS AND METHODS: Retrospective hospital study running from 2015 to 2018. We included all MCBA pregnancies between 15 and 25 weeks of gestation, with indications for in utero transfer. Our objective was to examine whether and why they were transferred and pregnancy outcomes. RESULTS: Of the 23 patients, 17 (73.9%) benefited from sanitary transfers. The survival rate of the fetuses in 15 pregnancies with Twin Oligo-Polyhydramnios Sequence (TOPS) was 73.3% for one twin and 53.3% for both twins. For the eight cases of Selective Termination of the pregnancy (ST), the survival rate of the twin was better with a transfer (n=5/6, 83.3%) than without a transfer (n=1/2 or 50%). The rate of premature rupture of the membranes after sanitary transfer among patients with TOPS was 63.6%. CONCLUSION: The sanitary transfer allows the management in expert center of complicated MCBA twin pregnancies, but is not always feasible and is accompanied by a high rate of premature ruptures of membranes.

Trends of Selective Fetal Reduction and Selective Termination in Multiple Pregnancy, in England and Wales: a Cross-Sectional Study.

Selective abortion was shown to be increasingly common in England and Wales over a 9-year period, occurring most frequently as twin to singleton reductions in the 1st trimester. We analysed the trends in selective abortion (SA) in multiple pregnancies in England and Wales between 2009 and 2018. This is a cross-sectional study looking at 1143 women with multiple pregnancies in England and Wales undergoing SA. There were a total of 1143 cases of SA between 2009 and 2018 in England and Wales, representing 0.07% of total abortions. There has been a steady increase in cases, from 90 in 2009 to 131 in 2018, with 82.3% justified under ground E of The Abortion Act 1967. The majority of SAs were carried out at 13-19 weeks gestation, and intracardiac injection of potassium chloride was the most prevalent method (75%). Twin to singleton reductions accounted for 59%, the most common form of SAs. Over half of all cases (59%) were performed in women aged 30-39 years, and 84% of all women were of White ethnicity. SA has been an option available for couples diagnosed with multiple pregnancy, especially when there are discordant anomalies. Although SA may decrease multiple pregnancy-related complications, preventative methods must be championed.

Late selective termination and the occurrence of placental-related pregnancy complications: A case control study.

INTRODUCTION: Multiple pregnancies are at increased risk of placental-related complications. The aim of the study was to investigate the prevalence and cumulative incidence of placental-related complications in twin pregnancies undergoing a late selective termination, compared to matched singleton and twin controls. METHODS: A retrospective case-control study of post-selective late termination (≥20 weeks of gestation) singletons performed between 2009 and 2020 at a single tertiary center. Each post-termination pregnancy was matched to 2 singleton and 2 dichorionic twin pregnancies for: mode of conception, maternal age group and parity. The prevalence of composite placental related outcome was determined and compared. Kaplan-Meier curves were constructed, and log rank test was performed to compare the cumulative incidence of placental complications among groups. RESULTS: Included were 90 post-selective termination pregnancies and 360 matched singletons and twins. These were subdivided according to trimester at procedure: 1) late 2nd trimester (N = 43, 20-27.6 weeks); 2) 3rd trimester (N = 47, ≥28 weeks). Placental-related complications presented earlier in the 3rd trimester selective termination group compared to singletons (median 35.5 vs median 37.4 weeks of gestation, P = 0.01). The cumulative incidence of placental-related complications in twins and post-selective termination singletons rose significantly earlier compared to singletons (P < 0.0001). A late 2nd trimester selective termination resulted in a comparable gestational age and cumulative incidence of placental-related complications as singletons. DISCUSSION: Compared to singletons, the cumulative incidence of placental complications rises significantly earlier in post-third trimester selective termination singleton pregnancies. While a late 2nd trimester selective termination results in a cumulative incidence comparable to singletons.

Monochorionic twins discordant for trisomy 13: A case report, systematic literature search and synthesis of available evidence.

This article presents the tenth reported case of monochorionic twins discordant for trisomy 13. Discordant aneuploidies in monochorionic twins are rare. Aetiologies include mitotic error in early cell division and "rescue" chromosome loss in an initially trisomic zygote. Clinicians should offer early amniocentesis of both sacs and consider selective termination.