Maternal plasma and amniotic fluid cytokines in monochorionic, diamniotic twin pregnancies complicated by twin-to-twin transfusion syndrome

Comparison of Pregnancy Outcomes of Previable and Periviable Rupture of Membranes After Laser Photocoagulation for Twin-Twin Transfusion Syndrome

OBJECTIVE

To describe the pregnancy outcomes of patients who experienced previable and periviable prelabor rupture of membranes (PROM) after the treatment of twin-twin transfusion syndrome.

METHODS

We conducted a retrospective cohort study of patients whose pregnancies were complicated by twin-twin transfusion syndrome who were treated with fetoscopic laser photocoagulation at a single fetal center and subsequently experienced PROM from April 2010 to June 2019. Outcomes were infant survival and latency from PROM to delivery. Patients were grouped by gestational age at PROM (before 26 weeks of gestation and 26 weeks or later). The group with PROM before 26 weeks of gestation was stratified by gestational age at PROM for further description of outcomes.

RESULTS

Two-hundred fifty of 653 patients (38%) developed PROM, 81 before 26 weeks of gestation and 169 after 26 weeks of gestation. In the setting of PROM before 26 weeks of gestation, the rate of survival of both twins to neonatal intensive care unit (NICU) discharge was 46.3%, compared with 76.9% in the setting of PROM at 26 weeks of gestation or later ( P <.001); the survival rate of at least one twin was 61.2% and 98.5%, respectively ( P <.001). Fourteen, 22, and 45 patients experienced PROM at 16-19 6/7, 20-22 6/7, and 23-25 6/7 weeks of gestation, respectively. Survival of both twins and at least one twin to NICU discharge was 25.0%, 47.4%, 52.8% (for two) and 33.3%, 47.4%, and 77.8% (for at least one), respectively, among those groups. Fifty-seven of the 81 patients with PROM before 26 weeks of gestation experienced a latency longer than 48 hours. In the setting of PROM before 26 weeks of gestation, when latency lasted longer than 48 hours, overall survival was improved (69.6% vs 53.7%, respectively, P =.017). With latency longer than 48 hours and PROM at 16-19 6/7, 20-22 6/7, and 23-25 6/7 weeks of gestation, survival of both twins to NICU discharge was 60.0%, 61.5%, and 60.7%, respectively, and survival of at least one twin was 80.0%, 61.5%, and 85.7%, respectively.

CONCLUSION

Earlier gestational age at PROM after laser photocoagulation is associated with longer latency but lower rates of survival. When PROM occurs before 26 weeks of gestation and latency exceeds 48 hours, rates of neonatal survival are significantly improved.

SARS-CoV-2 Infection and Inflammatory Response in a Twin Pregnancy

There is growing literature about the SARS-CoV-2 pathogenetic effects exerted during pregnancy and whether vertical transmission or premature birth is possible. It is not well known whether changes in the immune system of pregnant women may lead to a marked susceptibility to infectious processes and the risk of adverse maternal and neonatal complications such as preterm birth, spontaneous abortion, hospitalization in an intensive care unit, transmission to the fetus or newborns, and fetal mortality are poorly understood. Along with this ongoing debate, it is not well defined whether, during pregnancy, the role of host susceptibility in producing a specific inflammatory response to SARS-CoV-2 may represent distinctive markers of risk of vertical transmission. Furthermore, SARS-CoV-2 impact on the vaginal microbiome has not yet been described, despite mounting evidence on its possible effect on the gastrointestinal microbiome and its influence on infectious diseases and preterm labor. This report describes the impact of SARS-CoV-2 on a twin pregnancy diagnosed with infection at the third trimester of gestation including tissue infections, inflammatory response, antibody production, cytokine concentration, and vaginal microbiome composition. We identified a pattern of cytokines including IL1-Ra, IL-9 G-CSF, IL-12, and IL-8 differently expressed, already associated with previously infected patients. We detected a similar concentration of almost all the cytokines tested in both twins, suggesting that the SARS-CoV-2-induced cytokine storm is not substantially impaired during the placental passage. The analysis of the vaginal microbiome did not show relevant signs of dysbiosis, similar to other healthy pregnant women and twin healthy pregnancies. The aim of this report was to analyze the immunological response against SARS-CoV-2 infection and virus tissue tropism in a twin pregnancy.

Maternal vascular endothelial growth factor receptor and interleukin levels in pregnant women with twin-twin transfusion syndrome

Twin-twin transfusion syndrome (TTTS) is an unusual and serious condition that occurs in twin pregnancies when identical twins share a placenta but develop discordant amniotic fluid volumes. TTTS is associated with an increased risk of fetal death and birth defects if untreated. This study investigated the soluble levels of biomarkers including growth factors and interleukins in pregnant women with and without TTTS during pregnancy. We quantified plasma levels of VEGF-R1, VEGF-R2, IL-1β, IL-6 and IL-8 in twin pregnant women with (n=53) and without TTTS (n=72) and in women with single pregnancy (n=30) by ELISA and analyzed the association of maternal circulating biomarker levels with TTTS. Our results showed that maternal VEGF-R1 levels were significantly higher in twins compared to single pregnancy (P<0.05) and were decreased in the second trimester compared to the first trimester (P = 0.065, 0.019 and 0.072 for twins with and without TTTS and single pregnancy, respectively). VEGF-R2 levels had a trend to be lower in twins compared to single pregnancy. In addition, soluble VEGF-R1 and VEGF-R2 levels were significantly decreased while IL-6 levels were increased after surgical treatment with laser in twin pregnant women with TTTS (P = 0.016, 0.041 and 0.04, respectively). These results suggest that IL-6, VEGF-R1 and VEGF-R2 are involved in vascular regulation and stabilization in twin pregnancies and may contribute to the pathogenesis of TTTS and thus play a prognostic role in the surgical treatment of TTTS.

Evaluation of kidney injury biomarkers in rat amniotic fluid after gestational exposure to cadmium

Cadmium is a well-characterized nephrotoxic agent that is also capable of accumulating and diffusing across the placenta; however, only a few studies have addressed its effects over fetal kidneys and none of them has used a panel of sensitive and specific biomarkers for the detection of kidney injury. The goal of this study was to determine cadmium renal effects in rat fetuses by the quantification of early kidney injury biomarkers. Pregnant Wistar rats were exposed by inhalation to an isotonic saline solution or to CdCl2 solution (DDel =1.48 mg Cd kg(-1) day(-1) ) during gestational days (GD) 8-20. On GD 21, dams were euthanized and samples obtained. Kidney injury biomarkers were quantified in amniotic fluid samples and fetal kidneys were microscopically evaluated to search for histological alterations. Our results showed that cadmium exposure significantly raised albumin, osteopontin, vascular endothelial growth factor and tissue inhibitor of metalloproteinases-1 levels in amniotic fluid, whereas it decreased creatinine. Clusterin, calbindin and IFN-inducible protein 10 did not show any change. Accordingly, histological findings showed tubular damage and precipitations in the renal pelvis. In conclusion, gestational exposure to cadmium induces structural alterations in fetal renal tissue that can be detected by some kidney injury biomarkers in amniotic fluid samples. Copyright © 2016 John Wiley & Sons, Ltd.