New radiofrequency ablation procedure for selective reduction in complicated monochorionic twin or triplet pregnancy using multistep, incremental expansion technique.

OBJECTIVE: Radiofrequency ablation (RFA) is the preferred approach for selective reduction in complex monochorionic (MC) multiple pregnancies owing to the ease of operation and minimal invasiveness. To optimize the RFA technique and reduce the risk of adverse pregnancy outcome resulting from the heat-sink effect of RFA therapy, we used an innovative RFA method, in which an electrode needle was expanded incrementally and stepwise. This study aimed to assess the efficacy and safety profile of this novel multistep incremental expansion RFA method for selective fetal reduction in MC twin and triplet pregnancies. METHODS: This was a single-center retrospective cohort study of all MC multiple pregnancies undergoing RFA between March 2016 and October 2022 at our center. The multistep RFA technique involved the use of an expandable needle, which was gradually expanded during the RFA procedure until cessation of umbilical cord blood flow was achieved. The needle used for the single-step RFA method was fully extended from the start of treatment. RESULTS: In total, 132 MC multiple pregnancies underwent selective reduction using RFA, including 50 cases undergoing multistep RFA and 82 cases undergoing single-step RFA. The overall survival rates were not significantly different between the multistep and single-step RFA groups (81.1% vs 72.3%; P = 0.234). Similarly, the rates of preterm prelabor rupture of the membranes within 2 weeks after RFA, procedure-related complications, spontaneous preterm delivery and pathological findings on cranial ultrasound, as well as gestational age at delivery and birth weight, did not differ between the two groups. However, there was a trend towards a prolonged procedure-to-delivery interval following multistep RFA compared with single-step RFA (median, 109 vs 99 days; P = 0.377). Moreover, the fetal loss rate within 2 weeks after RFA in the multistep RFA group was significantly lower than that in the single-step RFA group (10.0% vs 24.4%; P = 0.041). The median ablation time was shorter (5.3 vs 7.8 min; P < 0.001) and the median ablation energy was lower (10.2 vs 18.0 kJ; P < 0.001) in multistep compared with single-step RFA. There were no significant differences in neonatal outcomes following multistep vs single-step RFA. CONCLUSIONS: Overall survival rates were similar between the two RFA methods. However, the multistep RFA technique was associated with a lower risk of fetal loss within 2 weeks after RFA. The multistep RFA technique required significantly less ablation energy and a shorter ablation time compared with single-step RFA in selective fetal reduction of MC twin and triplet pregnancies. Additionally, there was a trend towards a prolonged procedure-to-delivery interval with the multistep RFA technique. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Quadruplet pregnancy outcome with and without fetal reduction: Danish national cohort study (2008-2018) and comparison with dichorionic twins.

OBJECTIVES: To perform a nationwide study of quadrichorionic quadriamniotic (QCQA) quadruplet pregnancies and to compare the pregnancy outcome in those undergoing fetal reduction with non-reduced quadruplets and dichorionic diamniotic (DCDA) twin pregnancies from the same time period. METHODS: This was a retrospective Danish national register-based study performed using data from the national Danish Fetal Medicine Database, which included all QCQA quadruplets and all non-reduced DCDA twin pregnancies with an estimated due date between 2008 and 2018. The primary outcome measure was a composite of adverse pregnancy outcomes, including pregnancy loss or intrauterine death of one or more fetuses. Secondary outcomes included gestational age at delivery, the number of liveborn children, preterm delivery before 28, 32 and 37 gestational weeks and birth weight. Data on pregnancy complications and baseline characteristics were also recorded. Outcomes were compared between reduced and non-reduced quadruplet pregnancies, and between DCDA pregnancies and quadruplet pregnancies reduced to twins. A systematic literature search was performed to describe and compare previous results with our findings. RESULTS: Included in the study were 33 QCQA quadruplet pregnancies, including three (9.1%) non-reduced pregnancies, 28 (84.8%) that were reduced to twin pregnancy and fewer than three (6.1%) that were reduced to singleton pregnancy, as well as 9563 DCDA twin pregnancies. Overall, the rate of adverse pregnancy outcome was highest in non-reduced quadruplets (66.7%); it was 50% in quadruplets reduced to singletons and 10.7% in quadruplets reduced to twins. The proportion of liveborn infants overall was 91.1% of the total number expected to be liveborn in quadruplet pregnancies reduced to twins. This was statistically significantly different from 97.6% in non-reduced dichorionic twins (P = 0.004), and considerably higher than 58.3% in non-reduced quadruplets. The rates of preterm delivery < 28, < 32 and < 37 weeks were decreased in quadruplets reduced to twins compared with those in non-reduced quadruplet pregnancies. Quadruplets reduced to twins did not achieve equivalent pregnancy outcomes to those of DCDA twins. CONCLUSION: This national study of QCQA quadruplets has shown that multifetal pregnancy reduction improves pregnancy outcome, including a decreased rate of preterm delivery and higher proportion of liveborn children. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The outcome of reduced and non-reduced triplet pregnancies managed in a tertiary hospital during a 15-year-period - a retrospective cohort study.

OBJECTIVES: Triplet pregnancies involve several complications, the most important being prematurity as virtually all triplets are born preterm. We conducted this study to compare the outcomes of reduced vs. non-reduced triplet pregnancies managed in the largest tertiary hospital in Finland. METHODS: This was a retrospective cohort study in the Helsinki University Hospital during 2006-2020. Data on the pregnancies, parturients and newborns were collected from patient records. The fetal number, chorionicity and amnionicity were defined in first-trimester ultrasound screening. The main outcome measures were perinatal and neonatal mortality of non-reduced triplets, compared to twins and singletons selectively reduced of triplet pregnancies. RESULTS: There were 57 initially triplet pregnancies and 35 of these continued as non-reduced triplets and resulted in the delivery of 104 liveborn children. The remaining 22 cases were spontaneously or medically reduced to twins (9) or singletons (13). Most (54.4 %) triplet pregnancies were spontaneous. There were no significant differences in gestational age at delivery between triplets (mean 33+0, median 34+0) and those reduced to twins (mean 32+5, median 36+0). The survival at one week of age was higher for triplets compared to twins (p<0.00001). CONCLUSIONS: Most pregnancies continued as non-reduced triplets, which were born at a similar gestational age but with a significantly higher liveborn rate compared to those reduced to twins. There were no early neonatal deaths among cases reduced to singletons. Prematurity was the greatest concern for multiples in this cohort, whereas the small numbers may explain the lack of difference in gestational age between these groups.

Pregnancy outcomes of foetal reduction from twin to singleton gestation compared to ongoing twin gestations: a systematic review and meta-analysis.

BACKGROUND: Foetal reduction, which involves selectively terminating one or more foetuses in a multiple gestation pregnancy, has become more common. This systematic review and meta-analysis aims to assess and compare pregnancy outcomes of foetal reduction from twin to singleton gestation to ongoing twin gestations. METHODS: A comprehensive search of electronic databases (MEDLINE, EMbase, Cochrane Library, CINAHL and PsycINFO) was done for studies published until 15 April 2023. The outcomes analysed included gestational diabetes mellitus (DM), hypertension, caesarean delivery, foetal loss, perinatal death, preterm birth (PTB), intrauterine growth restriction (IUGR), preterm prelabour rupture of membranes (PPROM) and birth weight. RESULTS: A total of 13 studies comprising 1241 cases of twin to singleton foetal reduction gestation were compared to 20,693 ongoing twin gestations. Our findings indicate that foetal reduction was associated with a significantly lower risk of developing maternal gestational DM (odds ratio [OR] = 0.40, 95% confidence interval [CI] 0.27-0.59) and hypertension (OR = 0.36, 95% CI 0.23-0.57) compared to the control group. Incidence rate of caesarean delivery (OR = 0.65, 95% CI 0.53-0.81) after foetal reduction was significantly lower compared to ongoing twin gestations. There was a 63% lower chance of PTB before 37 weeks of pregnancy. However, there was no significant association between foetal reduction and outcomes such as foetal loss, perinatal death, IUGR and PPROM. CONCLUSIONS: Our findings suggest that foetal twin to singleton reduction entails potential benefits as compared to ongoing twin gestations. Further well planned studies are needed to explore underlying mechanisms to understanding of the outcomes associated with foetal reduction procedures and inform clinical decision-making for pregnant individuals and healthcare providers alike.

Foetal reduction, a procedure where one or more foetuses in a twin pregnancy are selectively terminated, has become more common. This study reviewed existing research to compare the outcomes of foetal reduction to singleton pregnancies with those of ongoing twin pregnancies. The study found that mothers who underwent foetal reduction had a lower risk of developing gestational diabetes and hypertension, and they were less likely to have a caesarean delivery. There was also a reduced chance of preterm birth before 37 weeks. However, foetal reduction did not appear to significantly impact outcomes like foetal loss, perinatal death, intrauterine growth restriction or preterm pre-labour rupture of membranes. It is important to note that there is some variation in the results among different studies, and more research is needed to fully understand these findings.

Intertwin nuchal translucency difference predicts the chance of co-twin death after fetal reduction in dichorionic triplet pregnancies: a retrospective analysis study.

OBJECTIVES: To compare the clinical outcomes of different multifetal pregnancy reduction (MFPR) programs in dichorionic (DC) triplets, and explore the association between early ultrasound characteristics and co-twin death after potassium chloride (KCl) injection into one monochorionic (MC) twin. METHODS: We retrospectively reviewed the data of DC triplets who underwent MFPR at our center during 2012-2021. Patients were grouped as follows: intracardiac KCl injection into one MC twin (group A), intracardiac KCl injection into both MC twins simultaneously (group B), and reduction of the singleton fetus (group C) and pregnancy outcomes were compared. Logistic regression was used to determine whether ultrasound measurements at 11-13+6 weeks predicted co-twin death and the receiver operator characteristic (ROC) analysis was conducted to assess the predictive performance. RESULTS: Finally, we enrolled 184 patients. 153 cases were in group A, and 18, 13 cases were in group B and C respectively. Gestational age at the time of MFPR did not differ among the 3 groups (median: [Formula: see text] weeks). The survival rate was 89.6%, 88.9%, and 92.3% in group A, B, and C respectively, which was comparable among groups. Preterm birth was more common in group C (10/12, 83.3%). After KCl injection into one MC twin, co-twin death occurred in 86.3% cases (132/153) within 1 day; however, 3 patients had 2 live births each, with normal postnatal development. Intertwin nuchal translucency (NT) difference/discordance significantly predicted co-twin death within 1 day after MFPR, and the areas under the ROC curve were 0.694 and 0.689, respectively. CONCLUSIONS: For MFPR in DC triplet pregnancies, reduction of the MC twins results in less preterm birth, and women with KCl injection into either one or both MC twins had similar outcomes. Large intertwin NT difference/discordance was associated with co-twin death within 1 day after KCl injection into one of the MC twins.

Outcomes of Elective Compared to Non-Elective Fetal Reduction by Radiofrequency Ablation in Monochorionic Multifetal Pregnancies.

INTRODUCTION: Higher order fetal gestation is associated with adverse pregnancy outcomes, and monochorionic (MC) pregnancies have unique complications. Multifetal pregnancy reduction (MPR) by radiofrequency ablation (RFA) may be used to optimize the outcomes of a single fetus. The purpose of this study was to determine whether pregnancy outcomes differ for elective reduction compared to reduction for medically complicated MC multifetal pregnancies. METHODS: This was a retrospective cohort of patients with MC twins and higher order multiples who underwent MPR via RFA at a single institution between 2008 and 2021. Patients undergoing elective reduction were compared to patients undergoing reduction due to a complication of MC pregnancy. Pregnancy outcomes were evaluated. RESULTS: Forty-eight patients who underwent RFA reduction between 2008 and 2021 were included in the analysis. Sixteen patients (33.3%) underwent elective RFA for MPR, and 32 (66.7%) underwent an RFA procedure for a complicated pregnancy. All pregnancies with RFA performed for elective indication had a continuing pregnancy (live birth rate 100%). There were no reported pregnancy losses within 4 weeks of the procedure when performed for a solely elective indication (n = 0) compared to 6.3% of complicated multifetal pregnancy (n = 2; 6.3%) (p = 0.001). CONCLUSION: In this retrospective cohort study, elective reduction of MC twins using RFA was associated with no cases of fetal loss or PPROM within 4 weeks of the procedure and a 100% live birth rate.

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 & 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) < 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 < 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.

Pregnancy and obstetric outcomes of dichorionic and trichorionic triamniotic triplet pregnancy with multifetal pregnancy reduction: a retrospective analysis study.

BACKGROUND: It is generally beneficial for triplet gestation or high-order multiple pregnancies to operate multifetal pregnancy reduction (MFPR) after assisted reproductive techniques. However, data on pregnancy outcomes is lacking regarding dichorionic triamniotic (DCTA) and trichorionic triplets (TCTA) pregnancy. METHOD: This research analyzes the difference between 128 DCTA and 179 TCTA pregnancies with or without MFPR after in vitro fertilization/intracytoplasmic sperm injection cycles between January 2015 and June 2020. The subdivided subgroups of the two groups are reduction to singleton, reduction to dichorionic twins, and expectant management groups. We also compare the pregnancy and obstetric outcomes between 2104 dichorionic twins and 122 monochorionic twins. RESULT: The research subgroups were DCTA to monochorionic singleton pregnancies (n = 76), DCTA to dichorionic twin pregnancies (n = 18), DCTA-expectant management (n = 34), TCTA to monochorionic singleton pregnancies (n = 31), TCTA to dichorionic twin pregnancies (n = 130), and TCTA-expectant management (n = 18). In DCTA-expectant management group, the complete miscarriage rate is dramatically higher, and the survival rate and the rate of take-home babies are lower. However, there was no difference between the rates of complete miscarriages, survival rates, and take-home babies in TCTA-expectant management group. But the complete miscarriage rate of DCTA-expectant management was obviously higher than that of TCTA-expectant management group (29.41 vs. 5.56%, p = 0.044). For obstetric outcomes, MFPR to singleton group had higher gestational week and average birth weight, but lower premature delivery, gestational hypertension rates and low birth weight in both DCTA and TCTA pregnancy groups (all p < 0.05). DCTA to monochorionic singleton had the lowest incidence of gestational diabetes, whereas The subdivided subgroups of TCTA had no significant difference in the incidence of gestational diabetes. Monochorionic twins have higher rates of complete, early, and late miscarriage, premature delivery, and late premature delivery, and lower survival rate (p < 0.05). CONCLUSION: MFPR could improve gestational week and average birth weight, reducing premature delivery, LBW, and gestational hypertension rates in DCTA and TCTA pregnancies. Monochorionic twins have worse pregnancy and obstetric outcomes. MFPR to singleton is preferable recommended in the pregnancy and obstetric management of complex triplets with monochorionic pair.

Early detection of ischemic brain injuries by diffusion-weighted imaging after radiofrequency ablation for fetal reduction in monochorionic pregnancies.

BACKGROUND: This study aimed to investigate the additional advantages of magnetic resonance imaging (MRI), particularly diffusion-weighted imaging (DWI) over fetal ultrasound in the detection of acute ischemic cerebral injuries in complicated monochorionic (MC) pregnancies that underwent selective reduction by radiofrequency ablation (RFA). METHODS: This prospective cohort study was conducted on 40 women with complicated MC pregnancies who were treated by RFA. Fetal brain imaging by DWI and conventional MRI was performed either in the early (within 10 days after RFA) or late phase (after 3-6 weeks) in the surviving fetuses to detect both acute and chronic ischemic injuries. The presence of anemia after RFA was also evaluated by Doppler ultrasound. RESULTS: Overall, 13 of the total 43 fetuses (30.23%) demonstrated MRI abnormalities with normal brain ultrasound results including germinal matrix hemorrhage (GMH), extensive cerebral ischemia, and mild ventriculomegaly. Although seven fetuses with GMH eventually survived, fetuses that demonstrated ischemic lesions and ventriculomegaly on MRI died in the uterus. CONCLUSION: The absence of abnormal cerebral lesions or anemia on ultrasound and Doppler exams does not necessarily rule out fetal brain ischemia. Performing early MRI, particularly DWI seems to be a reasonable option for detection of early intracranial ischemic changes and better management of complicated multiple pregnancies which were treated by RFA.

[Clinical effect of fetal reduction by intracranial and intrathoracic KCl injection].

OBJECTIVE: To evaluate the feasibility and effectiveness of fetal reduction by transabdominal intracranial KCl injection for multifetal pregnancies in the early second trimester. METHODS: The data of 363 patients who underwent transabdominal fetal reduction in the Reproductive Medical Center of Peking University Third Hospital from January 2006 to December 2019 were analyzed retrospectively. According to the location of fetal reduction, they were divided into two groups: Intracranial injection group (n=196) and intrathoracic injection group (n=167). The process of fetal reduction and pregnancy outcome of the two groups were compared. RESULTS: There was no significant difference between the two groups in the average age and the proportion of type of infertility before assisted reproductive technology, conception method, indication for fetal reduction, starting number of fetuses, reduced number of fetuses, and finishing number of fetuses (P>0.05). There was no significant difference between the two groups in the proportion of the number of puncture ≥ 2 times (12.1% vs. 8.6%, P=0.249) and the incidence of replacing puncture site (10.7% vs. 6.4%, P=0.161). The next day after fetal reduction, color Doppler ultrasound was rechecked. In the intracranial injection group and intrathoracic injection group, the incidence of fetal heartbeat recovery [3.6% (8/224) vs. 1.1% (2/187), P=0.188], the volumes of KCl used [(2.6±1.0) mL vs. (2.8±1.1) mL, P=0.079], and the abortion rate within 4 weeks after fetal reduction (1.0% vs. 0.6%, P=0.654) were of no significant difference. In addition, there was no significant difference in the total abortion rate after fetal reduction, premature delivery rate, cesarean section rate, delivery gestational week and neonatal birth weight between the two groups (P>0.05). CONCLUSION: Intracranial KCl injection can be an effective alternative to intrathoracic KCl injection for multifetal pregancy reduction.

The Changing Face of Feticide in Multiple Pregnancies.

The selective termination of one or more fetuses in higher order multiple pregnancies began in the 1980s in response to the increased rate of multiples arising from assisted reproductive technology (ART). Multifetal Pregnancy Reduction (MFPR) was justified by improving outcomes for the remaining offspring and their mother, and while the evidence suggests prematurity and the morbidity associated with it are reduced, there is a cost in increased miscarriage and mortality. As perinatal care has advanced, the margins of improvement have narrowed and hence the cost/benefit ratio. At the same time, MFPR has morphed from a rare procedure undertaken for quadruplets and higher, to one in which triplets and twins are increasingly reduced to a singleton, and more so for social reasons. This review considers the evidence for MFPR's efficacy and risks, along with those changes over time. Notably absent is research on the surviving children or the ongoing physical and mental health of mothers. The ethical reasoning used by practitioners and others is also explored, as is the culture of ART and abortion that drive the practice.

Management of 14 patients with cornual heterotopic pregnancy following embryo transfer: experience from the past decade.

OBJECTIVE: There are two major management approach for cornual heterotopic pregnancy, transvaginal cornual embryo reduction with ultrasound guidance, or laparoscopic cornual resection. This no consensus on the optimal management for cornual heterotopic pregnancy. Here, we are trying to determine the optimal management approach for patients with viable cornual heterotopic pregnancy following embryo transfer. METHODS: This is a retrospective cohort study conducted at the locally largest reproductive center of a tertiary hospital. A total of 14 women diagnosed as viable cornual heterotopic pregnancy following embryo transfer. Six patients were treated with cornual pregnancy reduction under transvaginal ultrasound guidance without the use of feticide drug (treatment 1), and eight patients were treated with laparoscopic cornual pregnancy resection (treatment 2). RESULTS: All 14 patients of cornual heterotopic pregnancy following embryo transfer due to fallopian tubal factor, among which, 12 patients had cornual pregnancy occurred in the ipsilateral uterine horn of tubal pathological conditions. Nine (64.29%) showed a history of ectopic pregnancy. Thirteen (92.86%) patients were transferred with two embryos and only one patient had single embryo transferred. Six patients received treatment 1, and 2 (33.33%) had uterine horn rupture and massive bleeding which required emergency laparoscopic surgery for homostasis. No cornual rupture occurred among patients received treatment 2. Each treatment group had one case of spontaneous miscarriage. The remaining 5 cases in treatment 1 group and the remaining 7 cases in treatment 2 group delivered healthy live offspring. CONCLUSION: Patients with tubal factors attempting for embryo transfer, especially those aiming for multiple embryos transfer, should be informed with risk of cornual heterotopic pregnancy and the subsequent cornual rupture. Compared with cornual pregnancy reduction under transvaginal ultrasound guidance, laparoscopic cornual resection might be a favorable approach for patients with viable cornual heterotopic pregnancy.

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.

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.

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.

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.

Transabdominal fetal reduction: a report of 124 cases.

To prevent fetal loss, preterm delivery, and perinatal morbidity of multifetal pregnancies (MPs), fetal reduction (FR) is offered to some patients. We retrospectively analysed the data of 124 MPs that underwent transabdominal FR to twin (n = 63) and singleton (n = 61) pregnancies at a mean gestational age of 12 + 6 weeks between December 2006 and January 2018. FR was performed transabdominally with the injection of potassium chloride into the intracardiac or intrathoracic space of the fetus or fetuses after ultrasound screening for nuchal translucency and anatomical defects. The initial number of embryos were 48 twins, 63 triplets, 11 quadruplets, and 2 quintuplets. The procedure-related pregnancy loss rate was 0.8% (1/124), the overall pregnancy loss rate was 2.4% (3/124), the fetal loss rate was 1.6% (2/124), and the neonatal death rate was 0.8% (1/124). The baby take-home rates were 96% for twin pregnancies and 96.7% for singletons. This study shows that transabdominal FR is an effective and safe procedure with a pregnancy loss rate of 2.4%.Impact statementWhat is already known on this subject? The incidence of multifetal pregnancies has increased over the years. Because multifetal pregnancies increase perinatal morbidity and mortality due to prematurity, fetal reduction is offed to some patients.What the results of this study add? The results of this study add to the growing body of research on fetal reduction. The study showed that transabdominal fetal reduction is a safe procedure with a pregnancy loss rate of 2.4%.What the implications are of these findings for clinical practice and/or further research? The results of this study can be used in counselling couples with multifetal pregnancies who are considering fetal reduction. Further research is needed to confirm the current findings.

Pregnancy outcome after multifetal pregnancy reduction of triplets to twins versus reduction to singletons.

RESEARCH QUESTION: Does fetal reduction of triplet pregnancies to singleton result in superior obstetric and neonatal outcomes compared with triplets reduced to twins? DESIGN: A historical cohort study including 285 trichorionic and dichorionic triplet pregnancies that underwent abdominal fetal reduction at 11-14 weeks in a single tertiary referral centre. The study population comprised two groups: reduction to twins (n = 223) and singletons (n = 62). Main outcome measures were rates of pregnancy complications, preterm delivery and neonatal outcomes. Non-parametric statistical methods were employed. RESULTS: Triplet pregnancies reduced to twins delivered earlier (36 versus 39 weeks, P < 0.001) with higher prevalence of Caesarean section (71.1% versus 32.2%, P < 0.001) compared with triplets reduced to singletons. Preterm delivery rates were significantly higher in twins compared with singletons prior to 37 weeks (56.9% versus 13.6%, P < 0.001), 34 weeks (20.2% versus 3.4%, P = 0.002) and 32 weeks (9.6% versus 0%, P = 0.01). No significant difference was found in the rate of pregnancy loss before 24 weeks (1.3% in twins versus 4.8% in singletons, P = 0.12) or in the rate of intrauterine fetal death after 24 weeks (0.4% versus 0%, P = 1.0). Both groups had comparable obstetrical complications and neonatal outcomes, except for higher rates of neonatal intensive care unit admission in twins (31.9% versus 6.8%, P < 0.001). CONCLUSIONS: Reduction of triplets to singletons rather than twins resulted in superior obstetric outcomes without increasing the procedure-related complications. However, because the rate of extreme prematurity in pregnancies reduced to twins was low, the overall outcome of those pregnancies was favourable. Therefore, the option of reduction to singletons should be considered in cases where the risk of prematurity seems exceptionally high.

Early intervention for heterotopic caesarean scar pregnancy to preserve intrauterine pregnancy may improve outcomes: a retrospective cohort study.

RESEARCH QUESTION: What is the best intervention time and method for patients who are diagnosed with heterotopic caesarean scar pregnancy (HCSP) wishing to preserve intrauterine pregnancy. DESIGN: Four patients diagnosed with HCSP from January 2014 to May 2019 were enrolled. Because HCSP is rare, data on 27 published cases were extracted to augment the analysis. Clinical characteristics and medical documents related to fetal reduction and subsequent maternal-neonate outcomes were analysed. RESULTS: The intervention time was significantly earlier in the full-term birth group (6.76 ± 1.05 weeks) compared with pre-term birth group (8.02 ± 1.55 weeks; P = 0.042). The cumulative full-term delivery rate was 91.48% when the intervention was at 6 weeks' gestation and decreased to 42.02% at 8 weeks. The maternal-neonate outcome was similar among the selective fetal reduction and surgical removal groups as was delivery time (34.68 ± 3.12 versus 34.80 ± 6.64 weeks; P = 0.955). In the four cases undergoing selective fetal reduction, the residual mass grew by 1.16-7.07 times compared with the area before reduction. The maximum size of the residual mass was observed at 12-13 weeks and 22-25 weeks. CONCLUSIONS: Most patients with HCSP who choose to keep intrauterine pregnancy will be able to carry the fetus to term. Selective fetal reduction would be the first intervention of choice and should take place immediately after diagnosis. The residual mass after reduction could continue to grow throughout the whole pregnancy, although this should not be considered as an indication for termination. With good supervision and careful management, the pregnancy could be maintained and carried to term.