Raman spectroscopy analysis of human amniotic fluid cells from fetuses with myelomeningocele.

Prenatal surgery for the treatment of spina bifida (myelomeningocele, MMC) significantly enhances the neurological prognosis of the patient. To ensure better protection of the spinal cord by large defects, the application of skin grafts produced with cells gained from the amniotic fluid is presently studied. In order to determine the most appropriate cells for this purpose, we tried to shed light on the extremely complex amniotic fluid cellular composition in healthy and MMC pregnancies. We exploited the potential of micro-Raman spectroscopy to analyse and characterize human amniotic fluid cells in total and putative (cKit/CD117-positive) stem cells of fetuses with MMC in comparison with amniotic fluid cells from healthy individuals, human fetal dermal fibroblasts and adult adipose derived stem cells. We found that (i) the differences between healthy and MMC amniocytes can be attributed to specific spectral regions involving collagen, lipids, sugars, tryptophan, aspartate, glutamate, and carotenoids, (ii) MMC amniotic fluid contains two particular cell populations which are absent or reduced in normal pregnancies, (iii) the cKit-negative healthy amniocyte subpopulation shares molecular features with human fetal fibroblasts. On the one hand we demonstrate a different amniotic fluid cellular composition in healthy and MMC pregnancies, on the other our work confirms micro-Raman spectroscopy to be a valuable tool for discriminating cell populations in unknown mixtures of cells.

Intramyometrial and intravenous oxytocin compared to intravenous carbetocin for prevention of postpartum hemorrhage in elective cesarean section-A quasi-randomized controlled phase IV non-inferiority interventional trial.

INTRODUCTION: Our objective was to assess non-inferiority of the unique approach used in our institution of combined 10 IU IM (intramyometrial) and 10 IU IV (intravenous) oxytocin to carbetocin IV in preventing severe postpartum blood loss in elective cesarean sections. The design was a prospective controlled phase IV non-inferiority interventional trial. The setting was a tertiary center at University Hospital, Zurich, Switzerland. MATERIAL AND METHODS: The population consisted of 550 women undergoing elective cesarean section after 36 completed weeks of gestation at low risk for postpartum hemorrhage (PPH). Participants were assigned to either combined oxytocin regimen (10 IU IM and 10 IU IV) or carbetocin (100 µg IV). Non-inferiority for oxytocin for severe PPH was assessed with a 0.05 margin using the Newcombe-Wilson score method. The main outcome measures were severe postpartum blood loss defined as delta hemoglobin (∆Hb, Hb prepartum-Hb postpartum) ≥30 g/L. RESULTS: Non-inferiority of combined oxytocin (IM/IV) in preventing severe postpartum blood loss was not shown (17 women in the oxytocin group vs. 7 in the carbetocin group). The number needed to treat when using carbetocin was 28. The risk difference for ∆Hb ≥30 g/L was 0.04 (oxytocin 0.06 vs. 0.03), 95% confidence interval (CI) (0.00-0.08). No significant difference was observed for ∆Hb (median 12 [IQR 7.0-19.0] vs. 11 [5.0-17.0], p = 0.07), estimated blood loss (median 500 [IQR 400-600] vs. 500 [400-575], p = 0.38), or the PPH rate defined as estimated blood loss ≥1000 mL (12[4.5] vs. 5 [2.0], risk difference 0.03, 95% CI (-0.01 to 0.06), p = 0.16). More additional uterotonics were administered in the oxytocin group compared to the carbetocin group (15.2% vs. 5.9%, p = 0.001). Total case costs were non-significantly different in the oxytocin group (US $ 10 146 vs. 9621, mean difference 471.4, CI (-476.5 to 1419.3), p = 0.33). CONCLUSIONS: Combined (IM/IV) oxytocin is not non-inferior to carbetocin regarding severe postpartum blood loss defined as postpartum Hb decrease ≥30 g/L in elective cesarean sections. We recommend carbetocin for use in clinical practice for elective cesarean sections.

Duration of labor in consecutive deliveries: a retrospective data analysis.

PURPOSE: Labor is shorter in multiparous women. However, there are no individualized data on differences in duration of labor for consecutive deliveries in the same parturient. METHODS: We conducted a retrospective data analysis from 2004 to 2021 at the University Hospital of Zurich and included all women with 2 or more vaginal deliveries of a singleton child in cephalic position, between 22 and 42 weeks of gestation. Descriptive statistics were performed with SPSS version 25.0 (IBM, SPSS Inc., USA). The primary endpoint was the ratio between durations of labor stages in consecutive deliveries of the same parturient. RESULTS: A total of 3344 women with 7066 births (2601 first [P0], 2987 s [P1], 1176 third [P2], and 302 fourth [P3]) were included. The ratio of duration of the active first stage of labor between P1 and P0 was 0.49 (95% CI 0.47-0.51, p < 0.001) meaning that the active first stage of labor was 51% shorter. The second stage of labor with a ratio of 0.26 (95% CI 0.24-0.27, p < 0.001) was 74% shorter in P1 compared to P0. Higher birthweight of the first child led to an even greater decrease in duration of the second stage of labor in P1 compared to P0 (p = 0.003). Neuraxial anesthesia was an independent risk factor for a longer duration of labor, irrespective of parity (p < 0.001). Birthweight and HC of the neonates did not significantly differ between the children born by the same women. However, higher birthweight in of the first child significantly augmented the rate of second stage of labor between P0 and P1 (p = 0.003). DISCUSSION: Up to the third delivery, duration of labor decreased with each consecutive delivery of the same parturient. An individualized assessment of the expected duration of labor in multiparous women should be encouraged.

Enhanced Recovery after Surgery in Open Fetal Spina Bifida Repair.

INTRODUCTION: For open fetal spina bifida (fSB) repair, a maternal laparotomy is required. Hence, enhanced maternal recovery after surgery (ERAS) is paramount. A revision of our ERAS protocol was made, including changes in operative techniques and postoperative pain management. This study investigates eventual benefits. METHODS: Our study included 111 women with open fSB repair at our center. The old protocol group (group 1) either received a transverse incision of the fascia with transection of the rectus abdominis muscle (RAM) or a longitudinal incision of the fascia without RAM transection, depending on placental location. The new protocol required longitudinal incisions in all patients (group 2). Postoperative pain management was changed from tramadol to oxycodone/naloxone. Outcomes of the two different protocol groups were analyzed and compared regarding the primary endpoint, the length of hospital stay (LOS) after fetal surgery, as well as regarding the following secondary endpoints: postoperative pain scores, day of first mobilization, removal of urinary catheter, bowel movement, and the occurrence of maternal and fetal complications. RESULTS: Out of 111 women, 82 (73.9%) were in group 1 and 29 (26.1%) were in group 2. Women in group 2 showed a significantly shorter LOS (18 [14-23] days vs. 27 [18-39] days, p = 0.002), duration until mobilization (3 [2-3] days vs. 3 [3-4] days, p = 0.03), and removal of urinary catheter (day 3 [3-3] vs. day 4 [3-4], p = 0.004). Group 2 less often received morphine subcutaneously (0% vs. 35.4%, p < 0.001) or intravenously (0% vs. 17.1%, p = 0.02) but more often oxycodone (69.0% vs. 18.3%, p < 0.001). No significant differences were seen regarding pain scores, bowel movement, and maternal and/or fetal complications. CONCLUSION: The new ERAS protocol that combined changes in surgical technique and pain medication led to better outcomes while reducing LOS. Continuous revisions of current ERAS protocols are essential to improve patient care continuously.

Chorioamniotic Membrane Separation after Fetal Spina Bifida Repair: Impact of CMS Size and Patient Management.

INTRODUCTION: Chorioamniotic membrane separation (CMS) is a known complication after fetal spina bifida (fSB) repair. This study's goal was to analyze women's outcomes with open fSB repair and CMS (group A) compared to the ones without (group B) and to assess the influence of CMS size and patient management. METHODS: A total of 194 women with open fSB repair at our center were included in this retrospective study. Outcomes of group A were compared to the ones of group B. Regression analysis was performed to assess risk factors for CMS. Two subgroup analyses assessed the impact of CMS size (small [A-small] vs. large [A-large]) as well as patient management (A1 = hospitalization vs. A2 = no hospitalization) on pregnancy outcomes. RESULTS: Of 194 women, 23 (11.9%) were in group A and 171 (88.1%) in group B. Preterm premature rupture of membranes (PPROMs) (69.6% vs. 24.1%, p = <0.001), amniotic infection syndrome (AIS) (22.7% vs. 7.1%, p = 0.03), histologically confirmed chorioamnionitis (hCA) (40.0% vs. 14.7%, p = 0.03), length of hospital stay (LOS) after fSB repair (35 [19-65] vs. 17 [14-27] days), and overall LOS (43 [33-71] vs. 35 [27-46] days, p = 0.004) were significantly more often/longer in group A. Gestational age (GA) at delivery was significantly lower in group A compared to group B (35.3 [32.3-36.3] vs. 36.7 [34.9-37.0] weeks, p = 0.006). Regression analysis did not identify risk factors for CMS. Subgroup analysis comparing CMS sized in group A-small versus A-large showed higher AIS rate (42% vs. 0%, p = 0.04), lower LOS (22.0 [15.5-42.5] vs. 59.6 ± 24.1, p = 0.003). Comparison of group A1 versus A2 showed longer LOS (49.3 ± 22.8 vs. 15 [15-17.5] days, p < 0.001), lower planned readmission rate (5.6% vs. 80%, p = 0.003). CONCLUSION: CMS significantly increased the risk of PPROM, AIS, hCA, caused longer LOS, and caused lower GA at delivery. Women with small CMS had higher AIS rates but shorter LOS compared to women with large CMS, while apart from LOS pregnancy outcomes did not differ regarding patient management (hospitalization after CMS yes vs. no).

Pain Scores after Open Fetal Spina Bifida Repair and Caesarean Section: A Longitudinal Cohort Study.

INTRODUCTION: In fetal surgery, successful pain management is crucial for postoperative mobilization, prophylaxis of contractions, and fast recovery. This study analyzed patient's pain experience after open fetal spina bifida (fSB) repair in comparison to pain scores after the subsequent Caesarean section (C-section). MATERIALS AND METHODS: Data were collected with a questionnaire given to 91 women, who had fSB repair and then C-section at our center between 2019 and 2022. It comprised 12 questions covering different aspects of pain experience and satisfaction with pain therapy and was answered by 67 women after fSB repair and 53 after C-section. Postoperative pain was rated on a Likert scale from 0 (slight/rarely) to 100 (strongest/always). Outcomes after fSB repair were compared to those after C-section. Additionally, subgroup analysis compared outcomes of women with different pain levels (group 1-5) after fSB repair. RESULTS: Compared to women after C-section women after fSB repair reported significantly higher maximum pain scores (MPS) (p = 0.03), higher sleep disturbance due to pain (p = 0.03), and sedation rates (p = 0.001) as side effect from pain therapy. No differences were found regarding feelings of insecurity (p = 0.20) or helplessness (p = 0.40), as well as involvement in (p = 0.3) and satisfaction with pain therapy (p = 0.5). Subgroup analysis revealed that women with higher MPS after fSB repair were significantly more often non-Caucasians (p = 0.003) and more often affected by pain while lying in bed (p = 0.007) and during mobilization (p = 0.005). Additionally, they reported higher rates of dizziness (p = 0.02) and lower satisfaction rates with pain therapy (p = 0.03). Postoperative complication rate did not differ among groups. CONCLUSION: Although women after fSB repair reported higher MPS compared to after C-section, the current pain management was generally perceived as satisfactory.

Fetal Spina Bifida Repair in Obese Mothers: Is Maternal and Fetal Safety Compromised?

INTRODUCTION: The Management of Myelomeningocele Study (MOMS) eligibility criteria preclude in utero surgery for fetal spina bifida (fSB) when the maternal body mass index (BMI) is ≥35 kg/m2. Some centers still respect this criterion, while others, like ours, do not. This study aimed to assess whether maternal and fetal safety is compromised with higher maternal BMIs. METHODS: Data of 192 patients with open fSB repair at our center were retrospectively analyzed. According to their BMI, patients were divided into three groups: group 1 (BMI <30 kg/m2), group 2 (BMI 30-35 kg/m2), and group 3 (BMI >35 kg/m2). Subgroup analysis was performed to assess differences in maternal and fetal outcomes. Additionally, complications were divided into grades 1 to 5 according to their severity and outcome consequences and compared among groups. RESULTS: Out of 192 patients, 146 (76.0%) had a BMI <30 kg/m2, 28 (14.6%) had a BMI 30-35 kg/m2, and 18 (9.4%) had a BMI >35 kg/m2. Significant differences occurring more often in either group 2 or 3 compared to group 1 were maternal wound seroma (50% or 56% vs. 32%, p = 0.04), amniotic fluid leakage (14% or 6% vs. 2%, p = 0.01) as well as vaginal bleeding (11% or 35% vs. 9%, p = 0.01). On the contrary, duration of tocolysis with atosiban was shorter in patients with BMI >30 kg/m2 (4 or 5 vs. 6 days, p = 0.01). When comparing severity of maternal or fetal complications, grade 1 intervention-related complications occurred significantly more often in group 3 compared to group 1 or 2 (78% vs. 45% or 57%, p = 0.02). Gestational age at delivery was around 36 weeks in all groups without significant differences. CONCLUSION: This investigation did not identify clinically relevant maternal and/or fetal outcome problems related to BMIs >35 kg/m2. Additional studies are however needed to confirm our results.

Second systolic peak in fetal middle cerebral artery Doppler after intrauterine transfusion.

OBJECTIVE: To evaluate functional relationship between fetal circulatory response to intrauterine transfusion (IUT) as a circulatory challenge and appearance of second systolic peak (P2) in middle cerebral artery (MCA) based on hemodynamic principles. METHODS: According to the concept of pulse wave (PW) propagation and reflection in adults, PWs arrive twice at cerebral circulation, as primary wave caused by left ventricle ejection and secondary after reflection in peripheral arteries. Thus adults show a biphasic contour of systolic blood flow in cerebral arteries. Similar waveforms may appear in fetal MCA-Doppler, as a response to IUT as a circulatory challenge. This is a proof-of-principle study, applying classical hemodynamic principles to fetal circulation. Accordingly, appearance of MCA-P2 may indicate vasoconstriction with increased PW reflection and timing of P2(Δt) should agree with the additional PW travel time down to reflection and return (Tr). To test this agreement, we searched our database for IUTs performed for severe fetal anemia, and compared Δt, obtained by Doppler, with Tr, obtained by hemodynamic calculation using human fetal data. Level of agreement was assessed using Bland-Altman-Plots. RESULTS: We identified 21 fetuses with adequate Doppler quality for Δt evaluation. In four cases (19%) MCA-P2 was observed before the intervention, and in 17 interventions (81%) thereafter; a highly significant association between IUT and P2 appearance (p < 0.001). In these 17 interventions good agreement of P2 timing was found between Doppler assessment: Δt = 80 ± 8 ms, and hemodynamic calculation: Tr = 76 ± 4 ms. CONCLUSION: P2 appearance in fetal MCA-Doppler seems to indicate PW reflection due to increased vasoconstriction after IUT. Thus hemodynamic considerations might enable Doppler monitoring of fetal vasoconstriction.

M-Sign in Middle Cerebral Artery Doppler Waveforms: A Sign of Fetal Vasoconstriction Before and After Open Fetal Spina Bifida Repair.

BACKGROUND: Increased pulse wave reflection in the fetal arterial system, illustrated by a second systolic peak (M-sign) in middle cerebral artery (MCA) Doppler waveforms, allows interpretation of fetal systemic vasoconstriction. Little is known about fetal vascular regulation during fetal spina bifida (fSB) repair. Therefore, the aim of this study was to analyze MCA-Doppler waveform changes before, during, and after fSB repair. PATIENTS AND METHODS: 31 pregnant women who underwent fSB repair were included. Fetal MCA-Doppler waveforms were prospectively analyzed before, during and after fSB repair, and categorized as follows: normal systolic downslope, systolic shoulder, second systolic peak (M-sign), and concave systolic downslope. These MCA waveforms were related to maternal and fetal characteristics, to anesthetic medication, and to umbilical artery (UA) waveforms. RESULTS: Before fSB repair, all fetuses repeatedly presented M-signs. After initiation of desflurane for general anesthesia, systolic shoulder and the M-sign vanished in 24/31 (78%) fetuses and 19/31 (61%) showed transient UA ARED flow. A significant association between these two Doppler findings was found (p=0.007). After fSB repair, signs of increased pulse wave reflection reappeared but resolved over time (23 days ± 20, SD) in all fetuses. CONCLUSION: Both fSB and intrauterine repair influence fetal vascular regulation. This phenomenon can be illustrated by MCA-Doppler waveforms. While anesthetic agents transiently eliminated M-signs and often provoked a UA ARED flow, fSB repair finally led to normalization of MCA-Doppler waveforms indicating return to normal fetal vascular regulation.

Prenatal Spina Bifida Repair: Defendable Trespassing of MOMS Criteria Results in Commendable Personalized Medicine.

INTRODUCTION: We hypothesize that after publication of the quintessence of the MOMS trial, eligibility criteria for prenatal spina bifida (SB) repair may be modified if a tenable argumentation underlies this decision. METHODS: Our first 154 fetal surgery patients were analyzed with particular focus on how many, which, and why the original eligibility criteria, set forth by the MOMS Trial Protocol, were disobeyed, and what the eventually detectable, negative and positive impacts of these deviations on outcomes were. RESULTS: A total of 152 patients (2 missing consent) were included (100%). In 69 patients (45.4%), a total of 89 eligibility criteria were disobeyed. In 54 (35.6%) cases, the following maternal criteria were concerned: gestational age at operation of >25+6 weeks in 17 (11.2%), uterine pathologies in 13 (8.6%) women, preoperative BMI ≥35 kg/m2 in 12 (7.9%), previous hysterotomy in 7 (4.6%), previous prematurity in 3 (2%), HIV/hepatitis B in 2 (1.3%), psychosocial issues in 2 (1.3%), and placenta praevia in 1 (0.7%). In 32 (21.1%) cases, fetal criteria were disobeyed 34 times: Fetal anomaly unrelated to SB in 19 (12.5%), no/minimal evidence of hindbrain herniation in 13 (8.6%), and severe kyphosis in 2 (1.3%). We could not identify cases where non-observation of criteria led to clear-cut maternal and/or fetal disadvantages. CONCLUSION: This study shows that MOMS trial eligibility criteria for prenatal SB repair should be modified or even abandoned with adequate medical and ethical argumentation, and with written parental informed consent after non-directive, full disclosure counseling. This clear-cut change of paradigm is a necessity as it leads toward personalized medicine, allowing more fetuses to benefit from fetal surgery than would have benefitted with the former, published, MOMS criteria in place.

Tissue Glue-Based Sealing Patch for the in vivo Prevention of Iatrogenic Prelabor Preterm Rupture of Fetal Membranes.

INTRODUCTION: One of the main concerns for all fetal surgeries is the risk of preterm delivery due to the preterm prelabor rupture of the fetal membranes (iPPROM). Clinical approaches to seal fetal membrane (FM) defects are missing due to the lack of appropriate strategies to apply sealing biomaterials at the defect site. METHODS: Here, we test the performance of a previously developed strategy to seal FM defects with cyanoacrylate-based sealing patches in an ovine model up to 24 days after application. RESULTS: Patches sealed tightly the fetoscopy-induced FM defects and remained firmly attached to the defect over 10 days. At 10 days after treatment, 100% (13/13) of the patches were attached to the FMs, and 24 days after treatment 25% (1/4) of the patches placed in CO2 insufflation, and 33% (1/3) in NaCl infusion remained. However, all successfully applied patches (20/24) led to a watertight sealing at 10 or 24 days after treatment. Histological analysis indicated that cyanoacrylates induced a moderate immune response and disrupted the FM epithelium. CONCLUSION: Together, these data show the feasibility of minimally invasive sealing of FM defects by locally gathering tissue adhesive. Further development to combine this technology with refined tissue glues or healing-inducing materials holds great promise for future clinical translation.

Determination of Anatomical Levels in Spina Bifida Fetuses with Ultrasound and MRI.

PURPOSE: The goal of this study was to assess the accuracy of prenatal anatomical level determination by ultrasound (US) and magnetic resonance imaging (MRI) by analyzing the congruence with the "true" anatomical level identified by postnatal MRI. PATIENTS AND METHODS: The first 60 patients undergoing fetal myelomeningocele surgery at The Zurich Center for Fetal Diangosis and Therapy were included in this study. Anatomical levels (i. e., first dysraphic vertebra) determined by prenatal US and MRI were compared to postnatal MRI. The level of agreement between the imaging modalities was evaluated with a Cohen's kappa test. Results > 0.6 were interpreted as good agreement, > 0.8 as excellent. RESULTS: The exact congruence between prenatal US and MRI compared to postnatal MRI was 33 % and 48 %, respectively, for an accuracy within one level difference of 80 % and 90 %, and within two levels difference of 95 % and 98 %, respectively. The level of agreement of prenatal US and MRI compared to postnatal MRI was 0.62 and 0.79, respectively. Most of the prenatally incorrectly assigned levels were assigned too high (worse) than the "true" level (US 88 % vs. MRI 65 %). CONCLUSION: Reliable exact prenatal level determination by US and MRI is not possible. However, the prenatal determination of the anatomical level of the lesion is good within one level margin of error. Prenatal US as well as MRI demonstrate a systematic error towards higher levels. The above considerations must be integrated into prenatal counselling.

Miniaturized Bioengineered Models for Preterm Fetal Membrane Healing.

INTRODUCTION: The reason for the absence of fetal membrane (FM) healing after a fetoscopic intervention is still unknown. We hypothesize that the lack of robust miniaturized models to study preterm FM functions is currently hampering the development of new treatments for FM healing. Specifically, miniaturized models to study preterm FM healing with minimal amounts of tissue are currently lacking. METHODS: In this study, we collected FMs from planned cesarean deliveries and developed different ex vivo models with an engineered biomaterial to study FM healing. Then, the effect of platelet-derived growth factor BB (PDGF-BB) on the migration of cells from preterm and term FMs was evaluated. RESULTS: FMs could be viably cultured ex vivo for 14 days. In a model of punctured FMs, migration of cells into FM defects was less pronounced than migration out of the tissue into the biomaterial. In a miniaturized model of preterm cell migration, PDGF-BB promoted migration of preterm amnion cells into the biomaterial. DISCUSSION AND CONCLUSION: By using a novel miniaturized model of preterm tissue, we here successfully demonstrate that PDGF-BB can promote preterm FM cell migration of microtissues encapsulated in a three-dimensional environment.

Fetal-Maternal Surgery for Spina Bifida in a HIV-Infected Mother.

INTRODUCTION: In select cases, in utero surgery for myelomeningocele (MMC) leads to better outcomes than postnatal repair. However, maternal HIV infection constitutes a formal exclusion criterion due to the potential of vertical HIV transmission. Encouraged by a previous case of a successful fetal spina bifida repair in a Hepatitis Bs antigen-positive woman, a plan was devised allowing for fetal surgery. CASE REPORT: In utero MMC repair was performed although the mother was HIV-infected. To minimize the risk of in utero HIV transmission, the mother was treated by highly active antiretroviral therapy throughout gestation as well as intravenous zi-dovudine administration during maternal-fetal surgery. The mother tolerated all procedures very well without any sequelae. The currently 20 month-old toddler is HIV negative and has significantly benefitted from fetal surgery. DISCUSSION/CONCLUSION: This case shows that maternal HIV is not a priori a diagnosis that excludes fetal surgery. Rather, it might be a surrogate for moving towards personalized medicine and away from applying too rigorous exclusion criteria in the selection of candidates for maternal-fetal surgery.

Subsequent Pregnancy Outcomes after Open in utero Spina Bifida Repair.

INTRODUCTION: Fetal spina bifida (SB) repair is a distinct therapeutic option in selected cases. Since this procedure may not only be associated with short-term obstetrical complications, the aim of this study was to assess the outcomes of subsequent pregnancies after open fetal SB repair. METHODS: 138 patients having had open fetal SB repair at our center received a questionnaire regarding the occurrence, course, and outcome of subsequent pregnancies. Additionally, medical records were reviewed. All subsequent pregnancies with complete outcome data that progressed beyond 20 gestational weeks (GW) were included for further analysis. RESULTS: 70% of all women answered the questionnaire. Out of this cohort, 35 subsequent pregnancies were reported in 29% of women. The rate of early pregnancy loss including elective terminations was 14%. All 29 pregnancies processing >20 GW ended in live births without preterm births <34th GW. Mean gestational age at delivery was 37.3 ± 1.4 GW. Uterine rupture occurred in two cases (7%) and uterine thinning/dehiscence was present in six cases (21%). No maternal transfusions were required. CONCLUSION: When counseling women undergoing open fetal SB repair, one should consider possible risks for subsequent pregnancies, especially the one of uterine dehiscence and rupture that is similar compared to numbers reported after classical cesarean deliveries.

In vivo Sealing of Fetoscopy-Induced Fetal Membrane Defects by Mussel Glue.

INTRODUCTION: The benefits of fetal surgery are impaired by the high incidence of iatrogenic preterm prelabor rupture of the fetal membranes (iPPROM), for which chorioamniotic separation has been suggested as a potential initiator. Despite the urgent need to prevent iPPROM by sealing the fetoscopic puncture site after intervention, no approach has been clinically translated. METHODS: A mussel-inspired biomimetic glue was tested in an ovine fetal membrane (FM) defect model. The gelation time of mussel glue (MG) was first optimized to make it technically compatible with fetal surgery. Then, the biomaterial was loaded in polytetrafluoroethylene-coated nitinol umbrella-shaped receptors and applied on ovine FM defects (N = 10) created with a 10 French trocar. Its sealing performance and tissue response were analyzed 10 days after implantation by amniotic fluid (AF) leakage and histological methods. RESULTS: All ewes and fetuses recovered well after the surgery, and 100% ewe survival and 91% fetal survival were observed at explantation. All implants were tight at explantation, and no AF leakage was observed in any of them. Histological analysis revealed a mild tissue response to the implanted glue. CONCLUSION: MG showed promising properties for the sealing of FM defects and thereby the prevention of preterm birth. Studies to analyze the long-term tissue response to the sealant should be performed.

Twin pregnancies.

Twin pregnancies, resulting in 2-3 % of all deliveries, are high risk pregnancies which need specialized care. A correct dating of pregnancy and the assessment of the chorionicity/amnionicity in the first trimester (< = 13 + 6 gestational weeks, GW) is essential for further monitoring. During first trimester risk stratification of monochorionic pregnancies includes evaluation of discordance of crown-rump-lengths, nuchal translucencies and amniotic fluid. At 16 GW sonographic risk evaluation of monochorionic twins involves differences in amniotic fluid and abdominal circumferences and detection of a velamentous cord insertion. A screening for fetal malformations with cervical length measurement as screening for preterm birth (cut-off < 25 mm) should be offered all twin pregnancies around 20 GW. In uncomplicated dichorionic pregnancies US examination should be performed every 4 weeks onwards to check fetal growth and amniotic fluid. An intertwin weight discordance > 20 % identifies pregnancies at increased risk of adverse outcome. Monochorionic pregnancies should be followed at least every two weeks for screening of twin-twin transfusion syndrome (TTTS), twin-anemia-polycythemia-sequence (TAPS) and selective fetal growth retardation (sFGR) with a start at 16 GW. The type 1-3 classification of sFGR in monochorionic twins depends on the pattern of end-diastolic velocity at the umbilical artery Doppler. The diagnosis of TTTS requires the presence of an oligyohydramnios (deepest vertical pocket (DVP) < 2 cm) in the donor twin and a polyhydramnios (DVP > 8 cm) in the recipient twin. However, the diagnosis of TAPS is based on the finding of discordant MCA Doppler values with a delta-MCA PV > 0.5 MoM.

Screening, Management and Delivery in Twin Pregnancy. / Überwachung und Betreuung von Zwillingsschwangerschaften (AWMF 015-087 S2e-Leitlinie).

The following AWMF guideline (DGGG/AGG & DEGUM responsible) deals with the diagnosis, screening and management of twins as well as the timing and mode of birth.Twin pregnancies can be classified as dichorionic diamniotic (DC DA), monochorionic diamniotic (MC DA) and monochorionic monoamniotic (MC MA) which are always monochorionic.Twin pregnancies can be concordant (both twins are affected) or discordant (only one twin is affected) for chromosomal defects, malformations, growth restriction and hemodynamic disorders.Chorionicity is the prognostically most significant parameter. Monochorial twins have significantly higher risks of intrauterine morbidity and mortality compared to dichorial twins.In particular, general aspects of twin pregnancies such as dating, determination of chorionicity and amnionicity, the labeling of twin fetuses and the perinatal switch phenomenon are discussed.Routine monitoring of MC and DC twin pregnancies with ultrasound at 11-13+ 6 weeks of gestation for chromosomal defects, invasive prenatal diagnosis, first-trimester NT or CRL discrepancies, early diagnosis of fetal anatomical defects, and management of twins with abnormalities, including selective fetocide, is described.Second trimester screening and management for preterm birth, intrauterine selective growth restriction (sFGR), classification of monochorial twins with sFGR, and management of the surviving twin after the death of the co-twin are described.Complications exclusively affecting MC twins include Twin to Twin Transfusion Syndrome (TTTS) with the important topics screening, prognosis, complications of laser therapy, timing of delivery, risks for brain abnormalities and delayed neurological development, Twin Anemia-Polycythemia Sequence (TAPS) and Twin Reversed Arterial Perfusion (TRAP) Sequence. This also includes MC MA twins as well as conjoined twins.Finally, the birth mode and time for DC and MC twin pregnancies are described.The information is summarized in 62 recommendations for action, 4 tables and 8 illustrations with comprehensive background texts.The guideline is an international guideline adaptation (ISUOG, NICE) as well as a systematic literature search and is up-to-date.

Hindbrain Herniation and Banana and Lemon Sign After Open Fetal Myelomeningocele Repair - When Do These Signs Disappear and is Shunting Predictable?

PURPOSE: The aim was to describe the sonographic follow-up of hindbrain herniation (HH), the banana and lemon sign after fetal myelomeningocele (fMMC) repair, and the time of disappearance of these signs after the intervention, and to investigate any predictive value for the necessity of shunting during the infant's first year of life. Additionally, the sonographic evolution of the transcerebellar diameter (TCD) before and after fetal intervention was assessed. PATIENTS AND METHODS: The first 50 patients that underwent fMMC repair at Zurich Center for Fetal Diagnosis and Therapy (www.swissfetus.ch) were included in this study. Sonographic scans performed weekly after fMMC repair focusing on HH and banana and lemon signs were analyzed and compared between the shunted and the non-shunted group. ROC curves were generated for the time intervals of resolution of the signs in order to show their predictive accuracy for the need for shunting until 1 year of age. RESULTS: HH resolved in 48 fetuses (96 %) before delivery. The sonographic disappearance of HH within the first two weeks after fMMC repair was associated with a significantly lower incidence of shunt placement (OR 0.19; 95 % CI 0.4-0.9) during the first year of life (p = 0.03). All fetuses with persistent HH before delivery received a shunt. TCD growth was observed in all fetuses. CONCLUSION: The reversibility of HH within two weeks after fMMC repair is associated with an 80 % lower incidence of shunt placement during the infant's first year of life. Moreover, it allows the cerebellum to grow and to normalize its configuration.

Minimally Invasive Precise Application of Bioadhesives to Prevent IPPROM on a Pregnant Sheep Model.

INTRODUCTION: Iatrogenic preterm premature rupture of the membrane remains the Achille's heel of fetoscopy. The aim of this study was to show in vivo feasibility of fetal membrane (FM) defect sealing by the application of tissue glues with umbrella-shaped receptors. METHODS: First, we adapted our previously described ex vivo strategy and evaluated the adhesion strength of different tissue glues, Histoacryl® and Glubran2®, by bonding polytetrafluoroethylene or silicone encapsulated nitinol glue receptor to human FM. Then, we exposed pregnant sheep uterus through a laparotomy and placed a 10-French trocar into the amniotic cavity through which the umbrella-shaped glue receptor (n = 9) was inserted and fixated onto the FM with the tissue glues (n = 8). The tightness of the sealed defects was assessed 4 h post-surgery. RESULTS: Both tissue glues tested resulted in adhesion of the glue receptors to the FM ex vivo. In vivo, all glue receptors opened in the amniotic cavity (n = 9) and all successfully placed glue receptors sealed the FM defect (n = 8). Four hours post-surgery, 2 treatment sites showed minimal leakage whereas the negative control without glue (n = 1) showed substantial leakage. DISCUSSION: This in vivo study confirms that fetoscopically induced FM defects can be sealed by the application of tissue adhesives.