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

Clinical outcomes of fetal selective reduction in dichorionic triplet pregnancies

BACKGROUND

It is recommended to reduce triplet pregnancy containing monochorionic (MC) twins to singleton. Given that some couples with infertility are eager to retain twins, better strategy is needed to avoid obstetrical risks and satisfy their strong wish. This retrospective observational study aimed to investigate the outcomes of triplet pregnancy reduction.

METHODS

Subjects with triplet pregnancies who underwent selective reduction between 2016 and 2019 at our hospital were enrolled. A total of 66 subjects with dichorionic triplet (DCT) with MC twins and an MC singleton were divided into two groups: group A (N = 38), reduced to dichorionic diamniotic (DCDA) twins; group B (N = 28), reduced to MC diamniotic (MCDA) twins. Obstetrical and perinatal outcomes were compared between groups.

RESULTS

Group A had significantly lower rates of early miscarriage (0% vs 14.3%, p = 0.028), cesarean section (81.6% vs 100%, p = 0.041), and late premature delivery (21.1% vs 45.4%, p = 0.047) than group B. Significantly higher rates of full-term delivery (71% vs 36.4%, p = 0.009) and take-home baby (100% vs 78.6%, p = 0.004), and higher gestational age at delivery (median: 38 [36.9, 39.0] vs 35.8 [34.4, 37.0] weeks, p < 0.001), total neonatal weight (2899.7 ± 647.6 vs 2354.4 ± 651.8 g, p < 0.001), weight of twins (2550 vs 2350 g, p = 0.039), and weight of larger neonate in twins (2790 vs 2500 g, p = 0.045) were observed in group A compared to group B.

CONCLUSION

DCT reduced to DCDA twins confers better pregnancy outcomes than into MCDA twins. This might benefit for triplet pregnancy subjects who strongly want to retain fraternal twins.

General Principles for Counseling and Management of Triplet Pregnancies

Compared with singleton pregnancies, triplet pregnancies are associated with a significantly increased risk of adverse pregnancy outcomes. Early ultrasound examination is the best way to diagnose triplets, establish dating, and determine the number of placentas to provide appropriate counseling and monitoring. Dichorionic placentation adds risks specifically associated with a shared placenta, and limits options for intervention. Multifetal reduction is an option that can significantly improve pregnancy outcomes compared with non-reduced triplet pregnancies. Integration of a Maternal-Fetal Medicine specialist in the prenatal care for a triplet pregnancy reduces the risk of preeclampsia, preterm birth, low birthweight infants, perinatal mortality, and major neonatal morbidity.

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.

Perinatal outcome of monochorionic triamniotic triplet pregnancy: multicenter cohort study

OBJECTIVE

Monochorionic (MC) triplet pregnancies are extremely rare and information on these pregnancies and their complications is limited. We aimed to investigate the risk of early and late pregnancy complications, perinatal outcome and the timing and methods of fetal intervention in these pregnancies.

METHODS

This was a multicenter retrospective cohort study of MC triamniotic (TA) triplet pregnancies managed in 21 participating centers around the world from 2007 onwards. Data on maternal age, mode of conception, diagnosis of major fetal structural anomalies or aneuploidy, gestational age (GA) at diagnosis of anomalies, twin-to-twin transfusion syndrome (TTTS), twin anemia-polycythemia sequence (TAPS), twin reversed arterial perfusion (TRAP) sequence and or selective fetal growth restriction (sFGR) were retrieved from patient records. Data on antenatal interventions were collected, including data on selective fetal reduction (three to two or three to one), laser surgery and any other active fetal intervention (including amniodrainage). Data on perinatal outcome were collected, including numbers of live birth, intrauterine demise, neonatal death, perinatal death and termination of fetus or pregnancy (TOP). Neonatal data such as GA at birth, birth weight, admission to neonatal intensive care unit and neonatal morbidity were also collected. Perinatal outcomes were assessed according to whether the pregnancy was managed expectantly or underwent fetal intervention.

RESULTS

Of an initial cohort of 174 MCTA triplet pregnancies, 11 underwent early TOP, three had an early miscarriage, six were lost to follow-up and one was ongoing at the time of writing. Thus, the study cohort included 153 pregnancies, of which the majority (92.8%) were managed expectantly. The incidence of pregnancy affected by one or more fetal structural abnormality was 13.7% (21/153) and that of TRAP sequence was 5.2% (8/153). The most common antenatal complication related to chorionicity was TTTS, which affected just over one quarter (27.6%; 42/152, after removing a pregnancy with TOP < 24 weeks for fetal anomalies) of the pregnancies, followed by sFGR (16.4%; 25/152), while TAPS (spontaneous or post TTTS with or without laser treatment) occurred in only 4.6% (7/152) of pregnancies. No monochorionicity-related antenatal complication was recorded in 49.3% (75/152) of pregnancies. Survival was apparently associated largely with the development of these complications: there was at least one survivor beyond the neonatal period in 85.1% (57/67) of pregnancies without antenatal complications, in 100% (25/25) of those complicated by sFGR and in 47.6% (20/42) of those complicated by TTTS. The overall rate of preterm birth prior to 28 weeks was 14.5% (18/124) and that prior to 32 weeks' gestation was 49.2% (61/124).

CONCLUSION

Monochorionicity-related complications, which can impact adversely perinatal outcome, occur in almost half of MCTA triplet pregnancies, creating a challenge with regard to counseling, surveillance and management. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Pregnancy incidence and associated risk factors of dichorionic triamniotic triplet under assisted reproduction: A large sample of clinical data analysis

BACKGROUND

Dichorionic triamniotic (DCTA) triplet pregnancies are rare in spontaneous pregnancy. The aim was to characterize the incidence and risk factors of DCTA triplet pregnancies after assisted reproductive technology (ART).

METHODS

A retrospective analysis of 10,289 patients, including 3,429 fresh embryo transfer (ET) cycle and 6,860 frozen ET cycle, was performed from January 2015 to June 2020. The effect of different ART parameters on the incidence of DCTA triplet pregnancies was evaluated by multivariate logistic regression analyses.

RESULTS

Among all clinical pregnancies after ART, the incidence of DCTA was 1.24%. 1.22% occurred in the fresh ET cycle, while 1.25% occurred in the frozen ET cycle. The number of ET and cycle type has no effect on the occurrence of DCTA triplet pregnancies (p = 0.987; p = 0.056, respectively). There were significant differences in DCTA triplet pregnancies rate among receiving intracytoplasmic sperm injection (ICSI) and receiving in vitro fertilization (IVF) [1.92% vs. 1.02%, p < 0.001, OR = 0.461, 95% confidence interval (CI) 0.315-0.673], blastocyst transfer (BT) versus cleavage-ET (1.66% vs. 0.57%, P < 0.001, OR = 0.329, 95% CI 0.315-0.673), and maternal age ≥ 35 years versus maternal age < 35 years (1.00% vs. 1.30%, P = 0.040, OR = 1.773, 95% CI 1.025-3.066). Based on the regression analysis of cycle type, DCTA triplet pregnancies rate was higher in maternal age < 35 years than in maternal age ≥ 35 years (1.35% vs. 0.97%, P < 0.001, OR = 5.266, 95% CI 2.184-12.701), BT versus cleavage-ET (1.47% vs. 0.94%; P = 0.006, OR = 0.346, 95% CI 0.163-0.735), and receiving ICSI was higher than receiving IVF (3.82% vs. 0.78%, p < 0.001, OR = 0.085, 95% CI 0.039-0.189) in fresh ET cycle. However, DCTA triplet pregnancies rate did not show difference in maternal age, insemination methods, and number of ET, and only BT was found to be associated with a higher DCTA triplet pregnancies rate in the frozen ET cycle (1.73% vs. 0.30%, p < 0.001, OR = 0.179, 95% CI 0.083-0.389).

CONCLUSION

The prevalence of DCTA triplet pregnancies has increased after ART. Maternal age < 35 years, BT, and receiving ICSI are risk factors for DCTA triplet pregnancies, also in fresh ET cycle. However, in frozen ET cycle, BT is an independent risk factor for increased DCTA triplet pregnancies rate.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Maternal, Perinatal and Neonatal Outcomes of Triplet Pregnancies According to Chorionicity: A Systematic Review of the Literature and Meta-Analysis

Triplet pregnancies are rare events that affect approximately 93 in 100,000 deliveries in the world, especially due to the increased use of assisted reproductive techniques and older maternal age. Triplet pregnancies are associated with a higher risk of fetal and maternal morbidity and mortality compared to twins and singletons. Chorionicity has been proposed as a major determinant of perinatal and maternal outcomes in triplet pregnancies, although further evidence is needed to clarify the extent and real influence of this factor. Thus, the aim of this study was to conduct a systematic review of the literature and a meta-analysis of the maternal and perinatal outcomes of triplet pregnancies, evaluating how chorionicity may influence these results. A total of 46 studies with 43,653 triplet pregnancies and 128,145 live births were included. Among the main results of our study, we found a broad spectrum of fetal and maternal complications, especially in the group of monochorionic and dichorionic pregnancies. Risk of admission to NICU, respiratory distress, sepsis, necrotizing enterocolitis, perinatal and intrauterine mortality were all found to be higher in non-TCTA pregnancies than in TCTA pregnancies. To date, our meta-analysis includes the largest population sample and number of studies conducted in this field, evaluating a wide variety of outcome measures. The heterogeneity and retrospective design of the studies included in our research represent the main limitations of this review. More evidence is needed to fully assess outcome measures that could not be studied in this review due to scarcity of publications or insufficient sample size.

Fetal reduction of triplet pregnancies to twins vs singletons: a meta-analysis of survival and pregnancy outcome

OBJECTIVE

This systematic review and meta-analysis aimed to compare the fetal survival rate and perinatal outcomes of triplet pregnancies after selective reduction to twin pregnancies vs singleton pregnancies.

DATA SOURCES

PubMed, Web of Science, Scopus, and Embase were systematically searched from the inception of the databases to January 16, 2022.

STUDY ELIGIBILITY CRITERIA

Studies comparing the survival and perinatal outcomes between reduction to twin pregnancies and reduction to singleton pregnancies were included. The primary outcomes were fetal survival, defined as a live birth at >24 weeks of gestation. The secondary outcomes were gestational age at birth, preterm birth at <32 and <34 weeks of gestation, early pregnancy loss (<24 weeks of gestation), low birthweight, and rate of neonatal demise (up to 28 days after birth).

METHODS

The random-effect model was used to pool the mean differences or odds ratios and the corresponding 95% confidence intervals. To provide a range of expected effects if a new study was conducted, 95% prediction intervals were calculated for outcomes presented in >3 studies.

RESULTS

Of note, 10 studies with 2543 triplet pregnancies undergoing fetal reduction, of which 2035 reduced to twin pregnancies and 508 reduced to singleton pregnancies, met the inclusion criteria. Reduction to twin pregnancies had a lower rate of fetal survival (odds ratio, 0.61; 95% confidence interval, 0.40-0.92; P=.02; 95% prediction interval, 0.36-1.03) and comparable rates of early pregnancy loss (odds ratio, 0.89; 95% confidence interval, 0.58-1.38; P=.61; 95% prediction interval, 0.54-1.48) and neonatal demise (odds ratio, 0.57; 95% confidence interval, 0.09-3.50; P=.55) than reduction to singleton pregnancies. Reduction to twin pregnancies had a significantly lower gestation age at birth (weeks) (mean difference, -2.20; 95% confidence interval, -2.80 to -1.61; P<.001; 95% prediction interval, -4.27 to -0.14) than reduction to singleton pregnancies. Furthermore, reduction to twin pregnancies was associated with lower birthweight and greater risk of preterm birth at <32 and <34 weeks of gestation.

CONCLUSION

Triplet pregnancies reduced to twin pregnancies had a lower fetal survival rate of all remaining fetuses, lower gestational age at birth, higher risk of preterm birth, and lower birthweight than triplet pregnancies reduced to singleton pregnancies; reduction to twin pregnancies vs reduction to singleton pregnancies showed no substantial difference for the rates of early pregnancy loss and neonatal death.

Maternal, fetal, and neonatal outcomes of elective fetal reduction among multiple gestation pregnancies: A systematic review

OBJECTIVE

To review the existing literature on fetal and maternal health outcomes following elective pregnancy reduction.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, the Cochrane Database of Systematic Reviews, and the Cochrane Controlled Trials Register.

STUDY SELECTION

Studies involving women pregnant with dichorionic twins, trichorionic triplets, or quadra-chorionic quadruplets who underwent elective fetal reduction of 1 or more fetuses to reduce the risks associated with multiple gestation pregnancies.

DATA EXTRACTION

The main fetal health outcomes measured were gestational age at delivery, preterm birth, miscarriage, birthweight, and small for gestational age at delivery. The main maternal health outcomes measured were gestational diabetes, hypertensive disorders of pregnancy, and cesarean delivery.

DATA SYNTHESIS

Of 7678 studies identified, 24 were included (n = 425 dichorionic twin pregnancies, n = 2753 trichorionic triplet pregnancies, and n = 111 quadra-chorionic quadruplet pregnancies). Fifteen studies (62.5%) did not report maternal health outcomes, while every study reported at least 1 fetal health outcome. Fetal reduction was associated with higher gestational age at birth, lower preterm birth, higher birthweight, and lower rates of small for gestational age infants and intrauterine growth restriction. No consistent pattern was observed for miscarriage and neonatal mortality rates. Following fetal reduction, cesarean delivery rates were lower in most studies. There were no appreciable trends with respect to gestational diabetes or hypertensive disorders of pregnancy.

CONCLUSION

Fetal reduction reliably optimizes gestational age at birth and neonatal birthweight. Miscarriage rates and other adverse procedural outcomes did not increase following transabdominal reduction. Further research on maternal outcomes is needed given a paucity of information in the literature.

Expectant management versus multifetal pregnancy reduction in dichorionic triamniotic (DCTA) triplets: Single centre experience

OBJECTIVES

In trichorionic triplet pregnancies, multifetal pregnancy reduction (MFPR) reduces the risk of preterm birth, neonatal morbidity and mortality without increasing miscarriage. A similar benefit has been suggested in dichorionic triamniotic (DCTA) pregnancy, but multiple methods are currently used. This study investigates if the method of reduction used in DCTA triplet pregnancy influences the evidence of benefit from MFPR.

METHODS

This is a retrospective cohort study of DCTA pregnancies between 2010 and 2019 who attended a single UK fetal medicine tertiary referral center. Cohorts were defined based on MFPR decision and method. The primary outcome was offspring survival until neonatal discharge. The secondary outcomes included miscarriage, preterm birth, livebirth, rates of small for gestational age (SGA) neonates, ans maternal morbidity. To evaluate the differences in neonatal survival until discharge we used Cox proportional regression to calculate hazard rates (HR) and 95% confidence intervals (CI). Differences in secondary outcomes were compared using univariate analysis.

RESULTS

The study reports the outcomes for 83 DCTA pregnancies. MFPR to DCDA twins was chosen in 19 pregnancies (14 radiofrequency ablation, RFA; 5 intrafetal laser, IFL); in 9 pregnancies selective reduction to a singleton was performed by KCl injection. The rate of pregnancies in with ≥ 1 fetus born alive was not different between groups (p = 0.90). However, the number of expected neonates alive at discharge from hospital was highest in the RFA group (89%, HR 0.28, 95% CI 0.21-0.87, p = 0.02). Rates of premature delivery before 32 weeks (p = 0.02), low birth weight (p < 0.001) and birthweight < 10th percentile (p = 0.01) were all elevated in the expectant management group, compared to women who opted for reduction. There was no difference in miscarriage between groups.

CONCLUSIONS

Our study suggests that MFPR by RFA, an established and widely available procedure, is of benefit in promoting neonatal survival until discharge in DCTA triplets.

Reduction of multiple pregnancy: Counselling and techniques

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

Reproductive outcome after cesarean scar pregnancy: A systematic review and meta-analysis

INTRODUCTION

To evaluate subsequent reproductive among women with a prior cesarean scar pregnancy (CSP).

MATERIAL AND METHODS

MEDLINE, Embase and ClinicalTrials.gov databases were searched. Inclusion criteria were women with a prior CSP, defined as the gestational sac or trophoblast within the dehiscence/niche of the previous cesarean section scar or implanted on top of it. The primary outcome was the recurrence of CSP; secondary outcomes were the chance of achieving a pregnancy after CSP, miscarriage, preterm birth, uterine rupture and the occurrence of placenta accreta spectrum disorders. Subgroup analysis according to the management of CSP (surgical vs non-surgical) was also performed. Random effect meta-analyses of proportions were used to analyze the data.

RESULTS

Forty-four studies (3598 women with CSP) were included. CSP recurred in 17.6% of women. Miscarriage, preterm birth and placenta accreta spectrum disorders complicated 19.1% (65/341), 10.3% (25/243) and 4.0% of pregnancies, and 67.0% were uncomplicated. When stratifying the analysis according to the type of management, CSP recurred in 21% of women undergoing surgical and in 15.2% of those undergoing non-surgical management. Placenta accreta spectrum disorders complicated 4.0% and 12.0% of cases, respectively.

CONCLUSIONS

Women with a prior CSP are at high risk of recurrence, miscarriage, preterm birth and placenta accreta spectrum. There is still insufficient evidence to elucidate whether the type of management adopted (surgical vs non-surgical) can impact reproductive outcome after CSP. Further large, prospective studies sharing an objective protocol of prenatal management and long-term follow up are needed to establish the optimal management of CSP and to elucidate whether it may affect its risk of recurrence and pregnancy outcome in subsequent gestations.

Ovarian hyperstimulation syndrome in a frozen-thawed embryo transfer pregnancy: a rare case report

Background

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication of ovarian stimulation. Prevention and early recognition of OHSS are important to ensure patient safety.

Case presentation

In this case, we reported a patient who underwent controlled ovarian hyperstimulation (COH) and in vitro fertilization (IVF). All embryos were cryopreserved to reduce possible OHSS. However, OHSS still occurred after the patient had a frozen-thawed embryo transfer (FET) with hormone replacement therapy (HRT) and obtained a dichorionic diamniotic triplet pregnancy. After multifetal pregnancy reduction (MFPR) and supportive treatment, all the symptoms regressed.

Conclusions

Prompt recognition of OHSS, especially in patients who have no history of ovulation induction and fresh embryo transfer, is very important. Multiple pregnancies may lead to severe OHSS because of the high level of human chorionic gonadotropin (hCG) in the early stages. We suggest that a single embryo transfer may be necessary and beneficial for patients.

Pregnancy outcomes of dichorionic triamniotic triplet pregnancies after in vitro fertilization-embryo transfer: multifoetal pregnancy reduction versus expectant management

Background

Trichorionic triplet pregnancy reduction to twin pregnancy is associated with a lower risk of preterm delivery but not with a lower risk of miscarriage. However, data on dichorionic triamniotic (DCTA) triplet pregnancy outcomes are lacking. This study aimed to compare the pregnancy outcomes of DCTA triplets conceived via in vitro fertilization-embryo transfer (IVF-ET) managed expectantly or reduced to a monochorionic (MC) singleton or monochorionic diamniotic (MCDA) twins at 11–13^+ 6 gestational weeks.

Methods

Two hundred ninety-eight patients with DCTA triplets conceived via IVF-ET between 2012 and 2016 were retrospectively analysed. DCTA triplets with three live foetuses were reduced to a MC singleton (group A) or MCDA twins (group B) or underwent expectant management (group C). Each multifoetal pregnancy reduction (MFPR) was performed at 11–13^+ 6 gestational weeks. Pregnancy outcomes in the 3 groups were compared.

Results

Eighty-four DCTA pregnancies were reduced to MC singleton pregnancies, 149 were reduced to MCDA pregnancies, and 65 were managed expectantly.

There were no significant differences among groups A, B, and C in miscarriage rate (8.3 vs. 7.4 vs. 10.8%, respectively) and live birth rate (90.5 vs. 85.2 vs. 83.1%, respectively) (P > 0.05).

Group A had significantly lower rates of preterm birth (8.3 vs. 84.6%; odds ratio (OR) 0.017, 95% confidence interval (CI) 0.006–0.046) and low birth weight (LBW; 9.2 vs. 93.2%; OR 0.007, 95% CI 0.003–0.020) than group C (P < 0.001).

Group B had significantly lower preterm birth (47.0 vs. 84.6%; OR 0.161, 95% CI 0.076–0.340) and LBW rates (58.7 vs. 93.2%; OR 0.103, 95% CI 0.053–0.200) than group C (P < 0.001).

Group A had significantly lower preterm birth (8.3 vs. 47.0%; OR 0.103, 95% CI 0.044–0.237; P < 0.001), LBW (9.2 vs. 58.7%; OR 0.071, 95% CI 0.032–0.162; P < 0.001) and perinatal death rates (1.3 vs. 9.1%; OR 0.132, 95% CI 0.018–0.991; P = 0.021) than group B.

Conclusion

The MFPR of DCTA triplets to singleton or MCDA pregnancies was associated with better pregnancy outcomes compared to expectant management. DCTA triplets reduced to singleton pregnancies had better perinatal outcomes than DCTA triplets reduced to MCDA pregnancies.

Perinatal mortality and morbidity in triplet pregnancy according to chorionicity: systematic review and meta-analysis

OBJECTIVE

The incidence of perinatal mortality and morbidity in triplet pregnancies according to chorionicity is yet to be established. The aim of this systematic review was to quantify perinatal mortality and morbidity in trichorionic triamniotic (TCTA), dichorionic triamniotic (DCTA) and monochorionic triamniotic (MCTA) triplets.

METHODS

MEDLINE, EMBASE and CINAHL databases were searched in December 2017 for literature published in English describing outcomes of DCTA, TCTA and/or MCTA triplet pregnancies. Primary outcomes were intrauterine death (IUD), neonatal death, perinatal death (PND) and gestational age at birth. Secondary outcomes comprised respiratory, neurological and infectious morbidity, as well as a composite score of neonatal morbidity. Data regarding outcomes were extracted from the included studies. Random-effects meta-analysis was used to estimate the risk of mortality and morbidity and to compute the difference in gestational age at birth between TCTA and DCTA triplet pregnancies.

RESULTS

Nine studies (1373 triplet pregnancies, of which 1062 were TCTA, 261 DCTA and 50 MCTA) were included in the analysis. The risk of PND was higher in DCTA than in TCTA triplet pregnancies (odds ratio (OR), 3.3 (95% CI, 1.3-8.0)), mainly owing to the higher risk of IUD in DCTA triplet pregnancies (OR, 4.6 (95% CI, 1.8-11.7)). There was no difference in gestational age at birth between TCTA and DCTA triplets (mean difference, 1.1 weeks (95% CI, -0.3 to 2.5 weeks); I²  = 85%; P = 0.12). Neurological morbidity occurred in 2.0% (95% CI, 1.1-3.3%) of TCTA and in 11.6% (95% CI, 1.1-40.0%) of DCTA triplets. Respiratory and infectious morbidity affected 28.3% (95% CI, 20.7-36.8%) and 4.2% (95% CI, 2.8-5.9%) of TCTA and 34.0% (95% CI, 21.5-47.7%) and 7.1% (95% CI, 2.7-13.3%) of DCTA triplets, respectively. The incidence of composite morbidity in TCTA and DCTA triplets was 29.6% (95% CI, 21.1-38.9%) and 34.0% (95% CI, 21.5-47.7%), respectively. When translating these figures into a risk analysis, the risk of neurological morbidity (OR, 5.4 (95% CI, 1.6-18.3)) was significantly higher in DCTA than in TCTA triplets, while there was no significant difference in the other morbidities explored. Only one study reported on outcomes of MCTA pregnancies, hence, no formal comparison with the other groups was performed.

CONCLUSION

DCTA triplets are at higher risk of perinatal mortality and morbidity than are TCTA triplets. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Clinical outcomes of multifetal pregnancy reduction in trichorionic and dichorionic triplet pregnancies: A retrospective observational study

OBJECTIVE

To observe the pregnancy and perinatal outcomes of trichorionic triplet (TCT) and dichorionic triplet (DCT) pregnancies with or without multifetal pregnancy reduction (MFPR).

MATERIALS AND METHODS

This was a retrospective study of 732 TCT and 118 DCT pregnancies after IVF/ICSI cycles between October 1999 and May 2014 at the Reproductive & Genetic Hospital of CITIC-Xiangya. The TCT and DCT groups were subdivided into three subgroups: MFPR to single fetus group, MFPR to twins group and expectant group. Pregnancy and perinatal outcomes were compared between different subgroups.

RESULTS

The resulting subgroups were TCT-Expectant (n = 40), TCT to twin (n = 610), TCT to single (n = 22), DCT-Expectant (n = 17), DCT to twin (n = 50), and DCT to single (n = 22). The groups with MFPR had the better pregnancy and perinatal outcomes. Meanwhile, the significantly higher abortion rates but lower live birth and take home baby rates were found in TCT-Expectant group and DCT-Expectant group (all P < 0.05). Besides, the abortion rate of DCT-Expectant group was much higher than TCT-Expectant group (41% verse 15%, P = 0.032). As for the perinatal outcomes, retaining single fetus group showed the advantage of higher birth weight, and elder gestational age in both DCT and TCT pregnancies (all P < 0.05).

CONCLUSION

For DCT and TCT pregnancies, MFPR application could reduce the miscarriage rate, while improving live birth and take home baby rates compared to the expectant groups. Especially, when reduced to a single fetus, MFPR could provide the better perinatal outcomes.

Risks of miscarriage or preterm delivery in trichorionic and dichorionic triplet pregnancies with embryo reduction versus expectant management: a systematic review and meta-analysis

STUDY QUESTION

Is pregnancy outcome in triplet pregnancies improved with embryo reduction (ER) to twins compared to expectant management?

SUMMARY ANSWER

In trichorionic triplet pregnancies, ER to twins reduces the risk of preterm birth (<34 weeks) without significantly increasing the risk of miscarriage (<24 weeks), whereas in dichorionic triplet pregnancies, the results are inconclusive.

WHAT IS KNOWN ALREADY

Triplet pregnancies are associated with a high risk of miscarriage and preterm birth. ER can ameliorate these conditions in higher order multiple gestations but is still controversial in triplets.

STUDY DESIGN, SIZE, DURATION

This study aimed to conduct a systematic review, following the PRISMA guidelines, and critically appraise ER at 8-14 weeks of gestation in both trichorionic triamniotic (TCTA) and dichorionic triamniotic (DCTA) pregnancies. Selective ER to twins was compared with expectant management, focusing on the risks of miscarriage and preterm birth. The computerized database search was performed on 8 January 2017. Overall, from 25 citations of relevance, eight studies with a total of 249 DCTA and 1167 TCTA pregnancies fulfilled the inclusion criteria.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A comprehensive computerized systematic literature search of all English language studies between 2000 and 2016 was performed in PubMed, EMBASE, Scopus, Evidence Based Medicine Reviews (Cochrane Database and Cochrane Central Register of Controlled Trials) and Google Scholar. Relevant article reference lists were hand searched. The management options were compared for rates of miscarriage <24 weeks and preterm birth <34 weeks. Only studies with both expectant management and ER to twins were included in the analysis. The quality of each individual article was critically appraised and appropriate statistical methods were used to extract results.

MAIN RESULTS AND THE ROLE OF CHANCE

In TCTA pregnancies managed expectantly (n = 501), the rates of miscarriage and preterm birth were 7.4 and 50.2%, respectively. Meta-analysis demonstrated that ER to twins in TCTA pregnancies (n = 666) was associated with a lower risk (17.3 versus 50.2%) of preterm birth (RR = 0.36, 95% CI: 0.28-0.48), whereas the risk of miscarriage (8.1% versus 7.4%) did not significantly increase (RR = 1.08, 95% CI: 0.58-1.98). In DCTA triplets managed expectantly (n = 200), the rates of miscarriage and preterm birth were 8.5 and 51.9%, respectively. Although the meta-analysis was inconclusive, it suggested that ER to twins in DCTA triplets, either of the foetus with a separate placenta (n = 15) or one of the monochorionic pair (n = 34), was neither significantly associated with an increased risk of miscarriage (8.5 versus 13.3%, P = 0.628 and RR = 1.22, 95% CI: 0.38-3.95, respectively) nor with a lower risk of preterm birth (51.9 versus 46.2%, P = 0.778 and RR = 0.5, 95% CI: 0.04-5.7, respectively).

LIMITATIONS, REASONS FOR CAUTION

No randomized controlled trials of ER versus expectant management in TCTA or DCTA pregnancies were identified from our literature search. We were able to include only a handful of papers with small sample sizes and suffering from bias, and non-English publications were missed. Irrespective of the strict inclusion and exclusion criteria, publication bias was evident.

WIDER IMPLICATIONS OF THE FINDINGS

The greatest strength of our systematic review is that, contrary to the existing literature, it only included studies with both the intervention and expectant arm. Our results are in agreement with current literature. In TCTA pregnancies, ER to twins is associated with a lower risk of preterm birth but is not associated with a higher risk of miscarriage. In the absence of a randomized trial, the data from systematic reviews appear to be the best existing evidence for counselling in the first trimester on the different options available. Finally, in DCTA pregnancies, indications exist that ER (of one of the MC pair) to twins could possibly reduce the risk of preterm birth without increasing the risk of miscarriage.

STUDY FUNDING/COMPETING INTEREST(S)

None to declare.

REGISTRATION NUMBER

N/A.

Intrafetal laser ablation for embryo reduction from dichorionic triplets to dichorionic twins

OBJECTIVE

To report the outcome of dichorionic (DC) triplet pregnancies reduced to DC twins by laser ablation of the pelvic vessels of one of the monochorionic (MC) twins.

METHODS

Intrafetal laser embryo reduction (ER) from DC triplets to DC twins was carried out in 61 pregnancies at 11 + 0 to 14 + 3 weeks' gestation. Pregnancy outcome was examined.

RESULTS

Intrafetal laser was successfully carried out in all cases, but ultrasound examination within 2 weeks of the procedure demonstrated that the MC cotwin had died in 28 (45.9%) cases and was alive in the other 33 (54.1%). In the DC group, there was one miscarriage at 23 weeks, one neonatal death after delivery at 26 weeks and in the other 31 cases there were two live births at a median gestational age of 35.3 (range, 30.4-38.4) weeks. In the 28 cases in which both MC fetuses died, there was one miscarriage at 16 weeks and in the other 27 cases the separate triplet was liveborn at a median gestation of 38.2 (range, 32.2-42.1) weeks. The overall rate of miscarriage was 3.3% (2/61) and that of preterm birth (PTB) at < 33 weeks was 6.8% (4/59).

CONCLUSIONS

In the management of DC triplet pregnancies, ER to DC twins by intrafetal laser ablation is associated with lower rates of miscarriage or early PTB, compared with expectant management or ER by fetal intracardiac injection of potassium chloride. However, about half of the pregnancies result in the birth of one rather than two babies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

DISCUSSION

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