Effect of a perineal protection device in vacuum-assisted births - a prospective randomized controlled interventional trial.

BACKGROUND: Birth tears are common after vaginal birth with a prevalence of up to 85%, especially in vaginal-assisted births. As birth trauma can cause physical and psychological short-term and long-term maternal morbidity, it is essential to improve maternal outcome at birth. OBJECTIVE: To evaluate the effect of a perineal protection device on the rate of spontaneous birth tears in the posterior compartment in vacuum-assisted births, as well as the feasibility and safety of the device. STUDY DESIGN: In a prospective, randomized controlled interventional trial from July 2020 to October 2022 we evaluated the application of a perineal protection device in vacuum-assisted vaginal births in a tertiary care center. 1998 patients were asked for participation, and 1574 patients with singletons ≥ 36 weeks of gestation gave their informed consent before birth. Ultimately, 209 were included according to a power calculation performed in advance with a statistical power of 80% and a significance level of 5% in expectation to reduce the rate for the primary composite outcome by 20%. The primary composite outcome was the rate of low-grade perineal and/or vaginal tears in the posterior compartment. Secondary outcomes were the rate of high-grade perineal tears and episiotomies, the feasibility of the device, and its safety for mother and child. Descriptive statistics and a logistic regression analysis were performed in an "intention-to-treat" (ITT), a "per-protocol" (PP), and an "as-treated" (AT) analysis, using SPSS version 29.0.0.0 (IBM SPSS, Armonk, New York, USA) and the software "R" (The R Project for Statistical Computing, version 3.5.0). A p-value < 0.05 was considered statistically significant. RESULTS: Of the 1574 patients, 249 (15.8%) had an indication for vacuum-assisted vaginal birth, of which 217 (13.8%) were randomized. Another eight patients (0.5%) were excluded because of birth ending without vacuum-assistance. Of the remaining 209 patients, 105 formed the intervention group (application of the device), whereas 104 formed the control group (without application of the device). No differences in primary and secondary outcomes were found in the ITT and PP analysis. In the ITT analysis, 79 patients (75.2%) in the intervention group compared to 73 patients (70.2%) in the control group (p = 0.4) met the primary endpoint. In the PP analysis, the primary composite outcome was seen 53 patients (77.9%) in the intervention group compared to 73 patients (70.2%) in the control group (p = 0.27). For the AT analysis, 68 of the 105 patients (65%) remained in the intervention group after exclusion of 37 (35%) patients with failed application of the device. Consequently, 141 formed the control group. In the AT analysis, there was also no difference in the primary composite outcome between the two groups (53 patients (77.9%) in the intervention group compared to 99 patients (70.2%) in the control group). However, within the secondary outcomes, we found a significantly lower rate of mediolateral episiotomies in the intervention group (29% vs 45%, p = 0.034). No adverse outcomes for mother and child were seen. In one third of cases, the device was difficult to place correctly and/or to keep correctly in place. CONCLUSION: The perineal protection device was not able to reduce the primary composite outcome of the study in women giving birth by vacuum-assistance. Although this was not the primary end point, a lower rate of mediolateral episiotomies was observed, if the device had been used correctly. As a limitation, difficulties with the application of the device occurred in 33% of cases. Nevertheless, no adverse events in association with the device were observed for either mother or child in our cohort. VIDEO ABSTRACT.

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.

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.

Success Rate and Long-Term Effects of Embolization of Pelvic Arteries for the Treatment of Postpartum Hemorrhage.

Introduction: Postpartum hemorrhage (PPH) is the leading cause of peripartal maternal mortality and accounts for 25% of all maternal deaths worldwide. The most common reasons of PPH are uterine atony, retained placenta, or placenta accreta spectrum. Treatment of PPH depends on the etiology and corresponds to a stepwise approach, which follows the German, Austrian and Swiss guideline for the diagnosis and therapy of PPH in Switzerland. In severe ongoing PPH, hysterectomy has been the ultima ratio for many decades. Nowadays, interventional embolization of the pelvic arteries (PAE) has become a popular alternative. Besides being a highly effective minimally invasive method, PAE avoids hysterectomy with consecutively reduced morbidity and mortality. However, data on the long-term effects of PAE on fertility and menstrual cycle are scarce. Methods: We performed a monocentric study consisting of a retro- and a prospective part including all women who had undergone a PAE between 2012 and 2016 at University Hospital Zurich. Descriptive characteristics of patients and efficacy of PAE defined as cessation of bleeding were analyzed retrospectively. In the prospective part, all patients were contacted for a follow-up questionnaire regarding menstruation and fertility after embolization. Results: Twenty patients with PAE were evaluated. Our data showed a success rate of PAE in 95% of patients with PPH; only 1 patient needed a second, then successful, PAE. No patient needed a hysterectomy or any other surgical intervention. In our study, an association between mode of delivery and identified etiology of PPH is observed. After spontaneous delivery (n = 6), the main reason of severe PPH was retained placenta (n = 4), while after cesarean section (n = 14), uterine atony was identified in most cases (n = 8). Regarding menstruation after embolization, all women reported regular menstruation after the breastfeeding period (100%). The majority reported a regular pattern with a shorter or similar duration (73%) and lower or similar intensity (64%). Dysmenorrhea decreased in 67% of patients. Four patients planned another pregnancy, of whom only one had become pregnant with assisted reproductive technology and ended up in a miscarriage. Discussion: Our study confirms the efficacy of PAE in PPH, thus obviating complex surgical interventions and associated morbidity. The success of PAE does not depend on the primary cause of PPH. Our results may encourage the prompt decision to perform PAE in the management of severe PPH in case of failure of conservative management and help physicians in the post-interventional counseling regarding menstruation patterns and fertility.

Information Gathering about Pregnancy, Birth, and Puerperium-Good and Fake Information.

Recent research on the subject of information-gathering processes among pregnant women has revealed a shift towards online sources. Health professionals' knowledge about sources of information has been shown to improve the understanding and counseling of patients. The objective of this study was to create an overview of all types of sources relevant to information gathering and to put their role and perception into perspective. METHODS: A total of 249 women were included in this study and recruited over a period of one month at the University Hospital of Zurich (USZ). Exclusion criteria included cases of fetal demise and late abortions. The survey on information-gathering processes was divided into three stages: pregnancy, birth, and puerperium. The different sources of information were compared based on women's characteristics. RESULTS: The response rate was 78% (n = 197). The main findings include a significant difference in information gathering based on varying levels of education, with women at the lowest educational level using the Internet the least during pregnancy (p = 0.029). During puerperium, significant differences could be observed in the involvement of the gynecologist. Primipara women as well as women of lower educational levels contacted their gynecologist less in contrast to multipara women (p = 0.006) and women of higher educational levels (p = 0.011). Overall, health professionals were considered to be the most important source of information. CONCLUSIONS: This study demonstrates that parity and educational level influence the information-gathering process. As the most important source for information gathering, health professionals must use this advantage to better assist their patients in accessing reliable information.

The Impact of Prepartum Platelet Count on Postpartum Blood Loss and Its Association with Coagulation Factor XIII Activity.

Background: Postpartum hemorrhage is a leading cause of maternal morbidity and mortality worldwide. Contradictory information exists regarding the relevance of prepartum platelet count on postpartum hemorrhage. We have shown prepartum coagulation factor XIII to be associated with postpartum blood loss; however, little is known about the association of platelet count with factor XIII activity. Our objectives were, first, to evaluate the impact of prepartum platelet count on measured postpartum blood loss in the context of prepartum measurements of coagulation factors I, II, and XIII and, second, to evaluate the association of platelet count with coagulation factor XIII, both pre- and postpartum. Material and Methods: This is a secondary analysis of a prospective cohort study (PPH 1,300 study) which analyzed the impact of prepartum blood coagulation factors on postpartum blood loss in 1,300 women. Blood loss was quantified using a validated technique. The impact of prepartum platelet count on measured blood loss was assessed by continuous outcome logistic regression; the association of platelet count with factor XIII activity by Spearman rank correlation. Results: Prepartum platelet count was significantly associated with measured postpartum blood loss: every one unit (G/L) increase in prepartum thrombocytes was associated with an odds ratio of 1.002 (95% confidence interval, 1.001-1.004, p = 0.005) to keep blood loss below any given cut-off level. This means that the probability of postpartum hemorrhage decreases with increasing prepartum platelet levels. Moreover, a significant association of platelet count with factor XIII activity was shown (Spearman rank correlation coefficient for prepartum values 0.228, p < 0.001, and for postpartum values 0.293, p < 0.001). Discussion/Conclusion: The significant association of prepartum platelet count and postpartum blood loss as well as the association of platelet count with blood coagulation factor XIII activity support the likely role of platelets in preventing postpartum hemorrhage and support the new guidelines for the treatment of postpartum hemorrhage in Germany, Austria, and Switzerland, which calls for optimizing platelet counts peripartally in case of postpartum hemorrhage. A possible effect of platelets on the level of circulating factor XIII cannot be ruled out and should prompt further investigation.

Evaluation of two rapid commercial assays for detection of Streptococcus agalactiae from vaginal samples.

INTRODUCTION: Streptococcus agalactiae, also known as group B streptococci (GBS), is associated with invasive infections in neonates. Identification of GBS vaginal colonization in pregnant women before delivery is essential for treatment with antibiotics to prevent intrapartum vertical transmission to the newborn. This study was designed to evaluate applicability of two rapid real-time PCRs in comparison to standard culture identification. MATERIAL AND METHODS: We compared the Xpert GBS assay, hereafter referred to as Xpert, and GenomEra GBS PCR, hereafter referred to as GenomEra. The standard culture identification consisted of two different agar plates as well as an enrichment broth. RESULTS: We analyzed vaginal samples of 260 pregnant women; 42 samples were tested GBS-positive by using standard culture as a gold standard, 30 by Xpert, and 37 by GenomEra. Xpert and GenomEra assays performed with sensitivities of 71.4% and 88.1% as well as specificities of 98.6% and 99.1%, respectively. Twelve vaginal samples were false-negative by Xpert and five samples by GenomEra. Interestingly, three negative Xpert results of standard culture-positive samples exhibited high Ct-values indicating the presence of GBS. If higher Ct-values are taken into consideration, the sensitivity of Xpert increases up to 78.6%. Moreover, only three Xpert PCRs had to be repeated, whereas two Genomera were invalid even after repetition and further 15 GenomEra PCRs were repeated because of borderline results or inhibition of the PCR test. CONCLUSIONS: In this study, GenomEra assay performed with a higher sensitivity than the Xpert PCR. On the other hand, the Xpert assay needs less hands-on-time for a sample preparation and requires approximately four-fold less repetitions as compared to the GenomEra assay. This robust performance of the Xpert assay make it applicable as a rapid intrapartum point-of-care test, although a higher sensitivity would be desirable. Therefore, culture in the 35-37 week of gestation remains the gold standard to detect vaginal colonization.

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.

2D pelvic floor ultrasound imaging in identifying levator ani muscle trauma agrees highly with 4D ultrasound imaging.

INTRODUCTION AND HYPOTHESIS: The objective was to evaluate the agreement between 2D and 4D translabial ultrasound (TLUS) technique in showing levator ani muscle (LAM) states after vaginal birth. METHODS: In a prospective observational cohort study between March 2017 and April 2019 we evaluated LAM states (intact, hematoma, partial, complete avulsion) of primiparous women having given birth vaginally with singletons in vertex presentation ≥ 36+0 gestational weeks by using 2D and 4D TLUS within 1-4 days postpartum (assessment A1) and again 6-10 weeks postpartum (assessment A2). Cohen's Kappa analysis was performed for each side separately to evaluate the test agreement between the two ultrasound techniques at every assessment period. RESULTS: A total of 224 women participated at A1 and 213 at A2. The agreement between the two ultrasound techniques was good to very good at A1 (Cohen`s kappa right-sided 0.78, left-sided 0.82) and very good at A2 (Cohen`s kappa both sides 0.88). The agreement was best when assessing an intact LAM or a complete avulsion (Cohen`s kappa between 0.78-0.92 for complete avulsions). CONCLUSIONS: The comparison between 2D and 4D TLUS showed a good to very good agreement in LAM trauma immediately after birth as well as 6-10 weeks postpartum. Therefore, 2D ultrasound could also be a valuable method for demonstrating a LAM abnormality and could be used in settings where 3D/4D ultrasound equipment is not available.

Acceptability and further potential of an app for maternal notes, the eMutterPass: A patient-centered online survey at the University Hospital Zurich.

OBJECTIVES: We wanted to characterize the acceptability of and women's satisfaction with the eMutterPass application. Particular attention was placed on concerns about data confidentiality and on willingness to use the app in an interactive way to share information about medication consumption. STUDY DESIGN: The present analysis is based on self-reported data from obstetric patients participating in an anonymous online survey between April 6th 2021 and April 20th 2021. RESULTS: During the 2-week timeframe, 1123 questionnaires were completed. The eMutterPass application was widely appreciated by our survey population and almost all participants would recommend the application to other pregnant women. A subpopulation analysis indicates that concerns about data confidentiality were higher among younger, multigravid and non-German-speaking pregnant women. The majority of women would be willing to report their medication use by taking pictures, filling in medication dosages or submitting assessments of perceived drug effectiveness. CONCLUSION: The development of our eMutterPass application meets the spirit of the times and gives pregnant women uncomplicated access to their own data. Concerns about data confidentiality can be adequately countered with additional information about the system structure. The largely positive adherence to the idea of reporting medication use on the app lays the groundwork for potential use of the eMutterPass for documentation of non-prescribed drugs.

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.

The evolution of levator ani muscle trauma over the first 9 months after vaginal birth.

INTRODUCTION AND HYPOTHESIS: The objective was to investigate the evolution of levator ani muscle (LAM) trauma over the first 9 months after birth and to evaluate their agreement between different assessment periods. METHODS: From March 2017 to April 2019 we prospectively evaluated LAM states (intact, hematoma, partial or complete avulsion) of primiparous women after vaginal birth by using 4D translabial ultrasound (TLUS) at three different assessment periods. All women were examined 1-4 days (A1) and 6-10 weeks (A2) postpartum, and women with a trauma additionally 6-9 months postpartum (A3). Cohen's Kappa analysis was performed to evaluate the test agreement between the assessment periods. RESULTS: Thirty-two percent of the women at A1 had a LAM trauma and 24% at A2. The higher number of LAM injuries at A1 can be explained by hematomas (14%), of which 51% spontaneously resolved at A2, 35% revealed themselves as partial, and 12% as complete avulsions. At A3, we observed anatomical improvement from complete to partial avulsions (23%) and few partial avulsions changed into an intact LAM (3%); none of the complete avulsions changed into an intact LAM. The agreement of 4D TLUS between A1 and A2 was moderate to good (0.64 for the right-sided LAM/0.60 for the left-sided LAM) and between A2 and A3 good to very good (0.76 right-sided/0.84 left-sided). CONCLUSIONS: Levator ani muscle trauma can reliably be diagnosed during all assessment periods. However, the agreement between A1 and A2 was only moderate to good. This can be explained by hematomas inside the LAM that were only observed early postpartum. We observed some anatomical improvement at A3, but no complete avulsion improved to an intact LAM.

Nalbuphine: a candidate for treatment of women overwhelmed with sudden, intense labor pain?

AIM: On very rare occasions, women are overwhelmed with sudden, intense labor pain in the context of ultra-rapid late second stage of labor, especially when the head is crowning. The consequences may comprise serious pelvic floor damage for the mother and hypoxia for the fetus. Drugs like nalbuphine for immediate maternal analgesia and sedation would be helpful. This mixed opioid agonist-antagonist, that was used in obstetric anesthesia in the 1980s, acts quickly while side effects for the mother are minor. To better estimate possible complications for the fetus of a use shortly before birth, it is important to find out how quickly i.v. administered nalbuphine reaches fetal circulation. Therefore, we characterized the transplacental transfer of nalbuphine using an ex vivo model. METHODS: Placentas were obtained from cesarean sections after mothers gave their informed consent. Upon cannulation of one cotyledon, nalbuphine was added to the maternal circuit (calculated final concentration 100 ng/mL) and the ex vivo placenta perfusions were performed. To determine nalbuphine transfer from maternal to fetal circuit in the successful perfusions (n = 5), samples were collected at different time points. RESULTS: At perfusion start, the measured initial nalbuphine concentrations in the maternal and fetal circuits are 93.1 and <0.1 ng/mL, respectively. After 5 min of placenta perfusion, 2.5 ng/mL nalbuphine (i.e. 3% of the initial nalbuphine concentration in the maternal circuit) is reached in the fetal circuit; after 15 and 30 min, 9.7 and 15.8 ng/mL (approximately 10 and 16% of initial maternal, respectively). CONCLUSIONS: Only a small amount of nalbuphine is likely to reach the fetus during the first minutes after (i.v.) maternal administration. Nalbuphine might be a valuable candidate for clinical use in the i.v. analgesia and sedation of women overwhelmed with sudden labor pain in the context of ultra-rapid second stage of labor.

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.

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.

Comprehensive quantitative characterization of the human term amnion proteome.

The loss of fetal membrane (FM) integrity and function at an early time point during pregnancy can have devastating consequences for the fetus and the newborn. However, biomaterials for preventive sealing and healing of FMs are currently non-existing, which can be partly attributed to the current fragmentary knowledge of FM biology. Despite recent advances in proteomics analysis, a robust and comprehensive description of the amnion proteome is currently lacking. Here, by an optimized protein sample preparation and offline fractionation before liquid chromatography coupled to mass spectrometry (LC-MS) analysis, we present a characterization of the healthy human term amnion proteome, which covers more than 40% of the previously reported transcripts in similar RNA sequencing datasets and, with more than 5000 identifications, greatly outnumbers previous reports. Together, beyond providing a basis for the study of compromised and preterm ruptured FMs, this comprehensive human amnion proteome is a stepping-stone for the development of novel healing-inducing biomaterials. The proteomic dataset has been deposited in the ProteomeXchange Consortium with the identifier PXD019410.

Reference Values for Umbilical Artery Lactate by Mode of Delivery and Gestational Age: A Retrospective Observational Study.

INTRODUCTION: Umbilical artery cord blood provides information about the intrauterine metabolism during labor. Umbilical artery lactate is a useful parameter in predicting neonatal morbidity, but data on normal values are limited. We aimed to provide reference ranges of umbilical artery lactate values across the combination of gestational age and mode of delivery. METHODS: A single-center retrospective observational study of liveborn infants born between 23 and 42 completed weeks gestation was conducted. Lactate, base deficit (BD), and pH from arterial cord blood were assessed between June 2018 and November 2020 and compared across gestational ages and modes of delivery. RESULTS: Overall, there were 3,353 infants with evaluable data. Lactate values at the 50th, 90th, and 97th percentile were 3.4, 7.0, and 9.0 mmol/L. Lactate was inversely correlated with pH (r = -0.77, p < 0.001) and positively correlated with BD (r = 0.63, p < 0.001). Lactate values changed significantly across gestational age (Kruskal-Wallis test, p < 0.001) which was attributable to an increase in lactate at 39-41 weeks gestational age. Also, lactate values were different across modes of delivery (Kruskal-Wallis test, p < 0.001) with lowest values in elective CS and highest values in vaginal instrumental deliveries. Comprehensive reference ranges across modes of delivery and gestational ages could be established. DISCUSSION: Mode of delivery and gestational age contribute to lactate levels with highest values occurring in vaginal instrumental deliveries and between 39 and 41 weeks gestational age. Based on these observations, we provide detailed reference ranges for clinical use.

Vacuum-Induced Tamponade for Treatment of Postpartum Hemorrhage.

BACKGROUND: Postpartum hemorrhage is a main cause of maternal mortality worldwide, with rising incidence, thus demanding new treatment approaches. Intrauterine balloon systems with application of intrauterine vacuum are a promising new method. METHOD: All women treated with vacuum-induced tamponade using a modified balloon system were included in this single-center study. Aiming to reduce uterine size for control of postpartum hemorrhage, the intrauterine balloon was filled to 50-100 mL and connected to a vacuum device. Success rate of vacuum-induced tamponade, defined as no need for additional interventional treatment, was analyzed by etiology of postpartum hemorrhage and time period of use. EXPERIENCE: Vacuum-induced tamponade was applied in 66 women. Success rate was 86% in women with uterine atony (n=44) and 73% in women with postpartum hemorrhage due to placental pathology (n=22). Success rate improved over the study period, culminating in a success rate of 100% in women with postpartum hemorrhage due to uterine atony in the second half of the observation period (n=22). CONCLUSION: This observational study supports our pathophysiologic understanding of uterine atony: to treat an atonic uterus, uterine volume must be reduced, leading to coiling of the uterine spiral arteries and, hence, reduced blood loss.

Retained placenta and postpartum hemorrhage: time is not everything.

PURPOSE: Postpartum hemorrhage is the major cause of maternal mortality worldwide. Retained placenta accounts for nearly 20% of severe cases. We investigated the influence of the time factor and retained placenta etiology on postpartum hemorrhage dynamics. METHODS: Our retrospective study analyzed a single-center cohort of 296 women with retained placenta. Blood loss was measured using a validated and accurate technique based on calibrated blood collection bags, backed by the post- vs pre-partum decrease in hemoglobin. We evaluated the relationship between these two blood loss parameters and the duration of the third stage of labor using Spearman rank correlation, followed by subgroup analysis stratified by third stage duration and retained placenta etiology. RESULTS: Correlation analysis revealed no association between third stage duration and measured blood loss or decrease in hemoglobin. A shorter third stage (< 60 min) was associated with significantly increased uterine atony (p = 0.001) and need for blood transfusion (p = 0.006). Uterine atony was significantly associated with greater decrease in hemoglobin (p < 0.001), higher measured blood loss (p < 0.001), postpartum hemorrhage (p = 0.048), and need for blood transfusion (p < 0.001). CONCLUSION: Postpartum blood loss does not correlate with third stage duration in women with retained placenta. Our results suggest that there is neither a safe time window preceding postpartum hemorrhage, nor justification for an early cut-off for manual removal of the placenta. The prompt detection of uterine atony and immediate prerequisites for manual removal of the placenta are key factors in the management of postpartum hemorrhage.