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

Outcome of monochorionic triamniotic triplet pregnancies: Expectant management versus fetal reduction

OBJECTIVE

To compare the outcomes of monochorionic triamniotic (MCTA) triplets managed expectantly with those reduced to twins.

METHOD

This was a retrospective cohort study comparing expectant management (EM) with fetal reduction (FR) to twins in 43 consecutive MCTA triplets with 3 live fetuses at 11-14 weeks between 2012 and 2021.

RESULTS

Nineteen patients managed expectantly and 24 triplets reduced to twins were included. The rate of pregnancy with at least one survivor was 84.2% in the EM group and 66.7% in the FR group (P=0.190). Compared to the EM cases, triplets reduced to twins had a higher median gestational age at delivery (36.0 weeks vs 33.3 weeks; P＜0.001), a higher mean birth weight (2244.3±488.6g vs 1751.1±383.2g; P<0.001) and a lower risk of preterm birth before 34 weeks (11.8% vs 64.7%; P=0.001). There were no significant differences in the risk of miscarriage, pregnancy complications and composite adverse neonatal outcomes.

CONCLUSION

In MCTA triplets, FR to twins could reduce the risk of preterm birth, whereas EM seems to be a reasonable choice when the priority is at least one survivor. However, due to the small sample size of this study, these findings must be interpreted with great caution. This article is protected by copyright. All rights reserved.

Middle Cerebral Artery Doppler Velocimetry for the Diagnosis of Twin Anemia Polycythemia Sequence: A Systematic Review

Twin anemia polycythemia sequence (TAPS) is a rare complication of monochorionic diamniotic (MCDA) twins. Middle cerebral artery peak systolic velocity (MCA-PSV) measurements are used to screen for TAPS while fetal or neonatal hemoglobin levels are required for definitive diagnosis. We sought to perform a systematic review of the efficacy of MCA-PSV in diagnosing TAPS. Search criteria were developed using relevant terms to query the Pubmed, Embase, and SCOPUS electronic databases. Publications reporting diagnostic characteristics of MCA-PSV measurements (i.e., sensitivity, specificity or receiver operator curves) were included. Each article was assessed for bias using the Quality Assessment of Diagnostic Accuracy Studies II (QUADAS II) tool. Results were assessed for uniformity to determine whether meta-analysis was feasible. Data were presented in tabular form. Among publications, five met the inclusion criteria. QUADAS II analysis revealed that four of the publications were highly likely to have bias in multiple areas. Meta-analysis was precluded by non-uniformity between definitions of TAPS by MCA-PSV and neonatal or fetal hemoglobin levels. High-quality prospective studies with consistent definitions and ultrasound surveillance protocols are still required to determine the efficacy of MCA-PSV in diagnosing TAPS. Other ultrasound findings (e.g., placenta echogenicity discordance) may augment Doppler studies.

Prevalence of Gestational Diabetes in Triplet Pregnancies: A Retrospective Cohort Study and Meta-Analysis

Background: Over the last decades, there has been a substantial increase in the incidence of higher-order multiple gestations. Twin pregnancies are associated with an increased risk of gestational diabetes mellitus (GDM). The literature on GDM rates in triplet pregnancies is scarce. Methods: A retrospective cohort study was performed to assess the prevalence of GDM in women with a triplet pregnancy. GDM was defined through an abnormal oral glucose tolerance test (OGTT). A meta-analysis of GDM prevalence was also carried out. Results: A cohort of 60 women was included in the analysis. Of these, 19 (31.7%) were diagnosed with GDM. There were no differences in pregnancy outcomes between women with and without GDM. In the meta-analysis of 12 studies, which used a sound GDM definition, an estimated pooled prevalence of 12.4% (95% confidence interval: 6.9–19.1%) was found. In a leave-one-out sensitivity analysis, the estimated GDM prevalence ranged from 10.7% to 14.1%. Conclusion: The rate of GDM seems increased in women with triplets compared to singleton pregnancies. However, GDM did not impact short-term pregnancy outcomes.

Fetal therapies as standard prenatal care in Japan

With recent advances in fetal medicine, various attempts have been made to save fetuses facing perinatal death or devastating consequences despite optimal management after birth. The concept of the fetus as a patient has been established through the application of in utero treatments. This paper reviews fetal therapies in order to highlight the role of perinatal medicine as standard prenatal care. Fetal therapies consist of medical therapy, percutaneous ultrasound-guided surgery, fetoscopic surgery, and open fetal surgery. In the 1980s, with advances in ultrasound imaging, percutaneous ultrasound-guided surgeries such as vesicoamniotic shunting for lower urinary tract obstruction and thoracoamniotic shunting (TAS) for fetal hydrothorax (FHT) were started. In the 1990s, fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS) was introduced, and later, a fetoscopic approach for congenital diaphragmatic hernia was also established. The revival of open fetal surgery, introduced in the 1980s by pediatric surgeons, began in the 2010s after a successful clinical study for myelomeningocele. Although many fetal therapies are still considered experimental, some have proven effective, such as FLS for TTTS, TAS for primary FHT, and radiofrequency ablation (RFA) for twin reversed arterial perfusion (TRAP) sequence. These three fetal therapies have been approved for coverage by Japan National Health Insurance as a result of clinical studies performed in Japan. FLS for TTTS, TAS for primary FHT, and RFA for TRAP sequence have become standard prenatal care approaches in Japan. These three minimally invasive fetal therapies will help improve the perinatal outcomes of fetuses with these disorders.

CaSR is required for ischemia-induced proliferation and differentiation of white matter progenitor cells from neonatal rats

This study was designed to investigate whether calcium-sensing receptor (CaSR) could induce immture white matter progenitor cells proliferation and differentiation into oligodendrocyte(OL) precursor cells after oxygen-glucose deprivation (OGD) in vitro. Progenitor cells of immature white matter originating from five-day-old newborn rats were divided into control, OGD, control + CaSR silencing, OGD + CaSR silencing, control + adenosine triphosphate magnesium chloride (ATP-MgCl2) and OGD + ATP-MgCl2 groups. Immunofluorescence, real-time RT-PCR, gene silencing, Hoechst 33342/propidium iodide (PI) and Flow cytometry tests were used to examine the proliferation, differentiation and survival of the white matter progenitor cells in the different treatment groups. The results showed that normal immature white matter progenitor cells have certain ability of self-proliferation and differentiation in vitro. OGD could further induce progenitor cells proliferation and differentiation into O4 + OL precursor cells by activating CaSR, but OGD also induced more necrosis and apoptosis of newborn cells and less MBP + OL formation. The addition of ATP-MgCl2 as an activating agent of CaSR further promoted cell proliferation and differentiation both under normal and OGD conditions and reduced OGD-induced apoptosis and necrosis, while CaSR silenced resulted in minimal cell proliferation, differentiation and survival. This study suggests that CaSR plays an important role in the induction of immature white matter progenitor cells proliferation and differentiation into OL precursor cells after OGD, which may provide a new angle to further study whether CaSR initiates the intrinsic repair potential of immature white matter after ischemia in vivo.

Fetoscopic laser photocoagulation for twin-twin transfusion syndrome

The aim of this study was to review fetoscopic laser photocoagulation (FLP), which ablates placental vascular anastomoses to treat twin–twin transfusion syndrome (TTTS). A review of studies reporting on the procedures, outcomes, complications and nonconventional applications of FLP for TTTS was conducted. FLP has been established as the primary treatment for monochorionic twin pregnancy associated with TTTS at 16–26 weeks. FLP is the only therapy that directly addresses the underlying pathophysiology. The recent technique modification of FLP, referred to as the ‘Solomon technique’, induces selective coagulation to connect the anastomoses ablation sites and has been introduced to reduce residual anastomoses. The perinatal survival following FLP improved significantly with advances in the technique after its introduction. The recent survival rates of both twins and at least one twin are 70% and more than 90%, respectively. However, there is still an 11–14% risk of long‐term neurodevelopment impairment. The premature rupture of membranes that leads to preterm labor is a common complication after FLP. FLP is a valuable treatment option for feto‐fetal transfusion syndrome in triplets and for TTTS after 26 weeks. FLP for selective intrauterine growth restriction may be potentially beneficial when accompanied by abnormal Doppler findings and oligohydramnios. FLP is the optimal treatment option for TTTS at 16–26 weeks of gestation. FLP appears to be applicable in triplets, TTTS after 26 weeks and cases of selective intrauterine growth restriction with abnormal Doppler findings and oligohydramnios. FLP is the most common and successful fetal intervention. Improvement in the neurodevelopmental outcomes after FLP is a future focus.