Vacuum Extraction Research Articles

Kinetics of hydrogen absorption/desorption in the Zr-2.5Nb alloy.

The Zr-2.5Nb alloy is a typical pressure tube material in heavy water nuclear reactors, and an increase of hydrogen isotope content in the alloy during service can pose major safety risks; hot vacuum extraction-mass spectrometry is an efficient method for evaluating hydrogen isotope concentrations in the Zr-2.5Nb alloy. This work investigates the kinetics and thermodynamic properties of deuterium (D) absorption and desorption of the Zr-2.5Nb alloy using the constant volume adsorption method and the hot vacuum extraction method. In addition to the previously reported volume contraction model, it was observed that at 600 °C and above, the reaction between D2 and Zr-2.5Nb is dominated by diffusion, while the reaction is predominantly influenced by surface adsorption and dissociation below 600 °C. Phase transition sequence of Zr-2.5Nb deuterides during non-isothermal desorption was established using quantitatively calibrated thermal desorption spectra combined with the phase transition process of deuteride decomposition. These results can provide important references for optimizing the process parameters of the hot vacuum extraction-mass spectrometry method.

748 Can Failed Vacuum Extraction Be Predicted?

748 Can Failed Vacuum Extraction Be Predicted?

Umbilical Cord Prolapse Managed by Assisted Vacuum Delivery

Umbilical Cord Prolapse Managed by Assisted Vacuum Delivery

834 Vacuum delivery for “Maternal Exhaustion” has distinctive characteristics

834 Vacuum delivery for “Maternal Exhaustion” has distinctive characteristics

Three-Dimensional Transperineal Ultrasound Guiding Early Secondary Repair of Obstetric Anal Sphincter Injury in an Incontinent Patient without Suture Dehiscence.

We present the case of a 36-year-old primigravida who gave birth to a 3200 g baby by vacuum-assisted (Kiwi OmniCup™) operative vaginal delivery with mediolateral episiotomy. A "y"-shaped perineal tear with a grade IIIC obstetric anal sphincter injury (OASI) was diagnosed and repaired. Two days after delivery, in the absence of suture dehiscence, she started experiencing complete anal incontinence. A decision was made in association with a proctologic surgeon for an early secondary repair. Before surgery, a Three-dimensional transperineal ultrasound (TPUS) was performed. The exam revealed a major defect of the external anal sphincter at the 11 o'clock position. This allowed for the reopening of only a circumscribed area of the perineal suture and repair of the sphincters using the end-to-end technique. The symptoms regressed completely, and follow-up TPUS demonstrated the gradual wound healing process. Anal incontinence, secondary to obstetric anal sphincter injury (OASI), has a severe negative impact on women's quality of life. TPUS is an effective method to detect sphincter defects and monitor the healing process. This report investigates the feasibility of identifying the sphincter tear in an incontinent puerperal patient without suture dehiscence in order to target early secondary repair while minimizing its extent. TPUS has proven a safe and effective tool to guide early secondary repair of symptomatic OASI complications while minimizing the invasiveness of the procedure. Multidisciplinary management is crucial to ensure the adequate standard of care.

EC conversion for 1:5 extracts and standard saturated soil–water pastes in the assessment of arid land salinization: Classical methodologies revisited

The common assessment of soil salinity posits a linear function, which transfers the electrical conductivity (EC) of highly diluted extracts to the standard state of soil paste. Our study examines this assumption and explains its limitations in a wide range of EC for highly saline soils of the Aral region in Uzbekistan. For a comparative EC assessment in the liquid phase from standard soil pastes and 1:5 aqueous extracts we used portable EC–meters. The dependences of EC, total dissolved solids (TDS), and soil–water potential on the pore water content were evaluated using centrifugation to separate the liquid phase from the soil matrix. The non-linearity of the relationship between the EC of water from soil pastes and 1:5 water extracts for both average and median data over a broad (0.4–160 dS/m) range of their variation is detected. A strong retention and concentration of electrolytes in fine pores and water films resistant to vacuum extraction, as well as the nonlinear EC versus TDS relationship in highly saline soils are attributed to this nonlinearity. A comprehensive statistical analysis showed that despite the general non-linearity, in the EC range from 0 to 30–35 dS/m, the results for 1:5 extract can be reliably converted to the standard state using the dilution model for the liquid phase of the soil with one basic parameter of soil bulk density. For hypersaline soils (EC > 30–35 dS/m), conversion based on the dilution theory is unacceptable due to a strong underestimation of TDS.

Internal manual rotation in intrapartal arrest of fetal head engagement

ObjectiveThe success of internal manual or digital rotation of the head in mechanical dystocia due to malpresentation, malposition or malrotation is presented in this paper on our own clinical material with reference of today's research and clinical recommendations. Study designThrough a retrospective bicentric clinical study, we investigated the success of internal head rotation in two University Clinics for gynecology and obstetrics from year 2017 to 2023. In 152 singleton term (37–42 weeks) in cases of persistens intrapartum arrest of the fetal head. After palpatory and ultrasonographically verified arrest of fetal head engagement, a therapeutic manual (Liepmann) or digital rotation was performed. ResultsIn 152 cases, manual rotation was performed in 108 (71.05 %) and digital rotation in 44 (28.94 %) cases in 73 (48.02 %) primiparous and 79 (51.97 %) multiparous. Intrapartum identification by digital palpation was done in all cases, and the following are: persistent occipital posterior position in 68 (44.73%), persistent deep transverse head presentation in 12 (7.89%), persistent high (longitudinal) occipital presentation in 64 (42.10 %) and persistent anterior asynclitism in 8 (5.26 %) cases. Episiotomy was used in 36 (23.68%) cases. Vacuum extraction was completed in 14 (9.21 %) deliveries, and cesarean section due to unsuccessful internal rotation in 15 (9.8 %) cases (%) without other indication. We did not record any intrapartum complications or cardiotocographic abnormalities. Cervical lacerations were treated with sutures in 4 cases (2.63 %). Successful correction of internal rotation procedure with spontaneous vaginal delivery was found in 80.92 % of cases. If we exclude delivery assisted by vacuum extraction whose indications were fetal hypoxia or dystocia after successful internal head rotation procedure, then the success rate of this method was 90.13 %. ConclusionInternal head rotation is a simple, safe and successful obstetric manual intervention that directly increases the rate of vaginal deliveries after correction of the birth mechanism anomaly and directly reduces the percentage of cesarean section. Manual or digital head rotation is an established midwifery/obstetric skill in several centers which, based on numerous clinical researches and experience, should become protocolized and included in the guidelines of professional associations.

Quantitative contribution of cryogenic vacuum extraction and radial water transport to xylem-source water deuterium offsets

The positions and magnitudes of deuterium offsets between bulk xylem and corresponding source waters are under debate and quantifying them is essential for isotope-based ecohydrological investigations. In this study, stable isotopes (δ2H, δ18O, and δ13C), iteration method, and rehydration experiments were combined to quantitatively determine the magnitude of cryogenic vacuum extraction (CVE)- and radial water transport (RWT)-induced deuterium offsets using one riparian tree species Salix babylonica L. A modified potential water source line (MPWL) was proposed to identify the total δ2H offsets between bulk xylem and source waters. The relationships between δ2H offsets induced by CVE or RWT and plant water content, leaf δ13C values, soil water content (SWC), and the depth to the water table (WTD) were investigated. Results showed that the bulk xylem waters in different tissue positions of S. babylonica showed −7.0 ‰ to −4.0 ‰ deuterium depletion relative to MPWL at four different sites (p < 0.01). The isotopic compositions of sap water coincided well with MPWL on the dual-isotope plot at the four sites. The CVE- and RWT-induced δ2H offsets accounted for 75.1 % and 24.9 % of the total δ2H offsets, respectively. The CVE-induced δ2H offsets were significantly negatively correlated with plant water content. In comparison, the RWT-induced δ2H offsets were negatively related to plant leaf δ13C values, trunk water content, and SWC, but positively correlated with WTD. This study provides a quantitative contribution of two major sources of deuterium offsets. The results provide critical insights into isotope-based plant water source identification and evapotranspiration partitioning.

Risk of Preterm Birth among Secundiparas with a Previous Cesarean due to a Failed Vacuum Delivery

Background: Studies have found an association between second-stage cesarean sections (SSCSs) and subsequent preterm birth (PTB). We aimed to evaluate if secundiparas with previous second-stage cesarean sections due to a failed vacuum delivery (SSCS-F-VD) are associated with PTB in the subsequent delivery compared with secundiparas with previous spontaneous vaginal birth (SVB) at term. A secondary aim was to compare this association with secundiparas with a previous SSCS at term. Methods: A historical, prospective, longitudinal cohort study was conducted in a large tertiary university hospital between 2006 and 2019. Matched mothers who experienced first and second births at the indexed hospital, excluding those with a previous miscarriage or multiple pregnancy in either the first or second birth were grouped based on the mode of delivery and gestational week of the first birth. Results: Parturients with term SVB and term SSCSs were less likely to experience PTB in the following delivery compared with those who underwent an SSCS-F-VD, with 496/14,551 (3.4%) versus 6/160 (3.8%) versus 5/61 (8.2%), respectively, at p &lt; 0.001. A logistic regression model revealed that secundiparas with previous SSCS-F-VD had an association with PTB in the following delivery compared with term SVB, with an OR of 2.756 (1.097; 6.922, p = 0.031). Conclusion: Previous SSCS-F-VD is associated with PTB in the following delivery, offering valuable insights for pregnancy management and patient counseling.

Seeing is Believing: Chasing Sevoflurane Vapor Trails

PurposeSevoflurane is an inhalational general anesthetic that has been used recently to treat chronic, painful lesions, reportedly supporting analgesia and wound healing. The potential for repeated exposure to off-gassed sevoflurane vapor, especially outside the air-conditioned operating theatre environment, is of some concern. DesignThis paper explores the qualitative and quantitative pathing of off-gassed sevoflurane from a topically applied liquid source. MethodsUsing a small, unventilated test-box (total volume 0.5 m3) with infra-red imaging and gas-analysing, we investigated the spatial distribution of sevoflurane vapor following complete vaporization of a 20 mL liquid sample. Utilizing the infra-red absorption of sevoflurane, it was possible to visualize (as an apparent reduction in temperature) the streaming path of the sevoflurane vapor. Sevoflurane levels (%) in the test-box were measured using an infra-red gas analyzer. FindingsIn keeping with its higher density than air, sevoflurane vapor was seen to “waterfall” from the liquid source and accumulate in the bottom of the test-box. Sevoflurane vapor concentration was minimal above the liquid source. When extrapolated to a larger (unventilated) room, we estimate that the sevoflurane concentration would be less than 10 ppm one centimetre above the liquid pool. With vacuum extraction, these levels would be even lower. ConclusionsDue to sevoflurane’s tendency to accumulate on the floor, it is concluded that topical application of liquid sevoflurane posses virtually no risk to off-gas exposure in unventilated spaces.

Vacuum-assisted caesarean delivery assessment of maternal &amp; fetal outcome

: The baby is delivered via incisions made in the mother's abdomen and uterus during a Caesarean delivery, sometimes known as a C-section. Whether medically necessary or elective, caesarean sections have increased sharply in recent decades all throughout the world, exceeding the WHO-recommended 10-15% rate. Every effort should be taken to give cesarean sections to women in need rather than aiming to achieve a target rate, according to a 2015 WHO statement. Therefore, we must investigate the strategies that can improve CD's maternal and neonatal health condition. This study compares the outcomes for the mother and the newborn in the vacuum-assisted CD and manual CD groups.: A progressive study was conducted at Lucknow's Green cross Hospital between June 2012 and April 2018. 500 pregnant ladies took part in this study as participants. This research was approved by the institutional human ethical committee. 250 caesarean sections were performed as part of this cohort study, each with vacuum assistance utilizing a soft cup vacuum extractor on the fetal scalp and manual removal of the skull as usual with fundal compression as support. Due to the absence of uterine activity and amniotic fluid, all of the patients underwent preplanned caesarean sections. The study's findings showed that manual extraction Caesarean birth is inferior to vacuum-assisted Caesarean delivery. Additionally, it was noted that Vacuum Assisted Caesarean Delivery resulted in less uterine incision extension, estimated blood loss, and maternal discomfort. : There was no difference between Vacuum and Manual Extraction caesarean deliveries in terms of Apgar Score, the requirement for infant resuscitation, or admission to the NICU.

Determining the source water and active root depth of woody plants using a deuterium tracer at a Savannah site in northern Stampriet Basin, Namibia

Woody plants play a significant role in the global water cycle through water uptake by roots and evapotranspiration. A deuterium tracer was used to assess the active root depths for Salvia mellifera and Boscia albitrunca in the Ebenhaezer area (western Namibia). The tracer was inserted at different soil depths in December 2016. Xylem cores were obtained using an increment borer, and transpired water was collected using transpiration bags zipped around the plants’ leaves. Groundwater was collected from boreholes. Soil samples were collected after the rainy season using a hand auger. Xylem and soil water were extracted using a cryogenic vacuum extraction method and analysed for stable water isotopes. Only one S. mellifera transpiration sample showed a high deuterium content (516‰) where the tracer was inserted at 2.5-m soil depth. Elevated deuterium contents were observed in two S. mellifera xylem samples; tracer had been applied at 2.5 and 3 m depth (yielding 35 and 31‰ deuterium, respectively), which constitutes a possible active-root depth range for S. mellifera. At the end of the study period (May 2017), the average δ18O value for B. albitrunca xylem samples was similar to that of groundwater. The δ18O value for S. mellifera was between that of soil water and groundwater, indicating that this species uses groundwater and soil water available for groundwater recharge. Determination of the active root depth and source water for these species would help improve hydrological modelling by incorporating the influence of woody plants on groundwater recharge.

Frequency of digital vaginal examination and associated factors among mothers admitted to labor and delivery wards in public health facilities of Arba Minch town, southern Ethiopia.

To assess the frequency of digital examination and its associated factors among laboring mothers in public health facilities in Arba Minch town, southern Ethiopia. Digital vaginal examination (DVE) is the commonly applied clinical assessment method used to discover the progress of labor and delivery. However, frequent DVE may not be free of risk for maternal and neonatal health, and pain during intrapartum care. An institution-based descriptive cross-sectional study was employed from May 3 to July 6, 2022. Study participants were selected by a serial sampling method. Data were entered into epi data version 7.2 and exported to SPSS v.25 for data analysis. Binary and multivariate logistic regression analyses were employed to assess associations between study variables. Statistical significance was declared at a P value less than 0.05. A total of 374 women responded to the interview, making a response rate of 98.4%. In all, 230 (61.5%) of the laboring mothers underwent five or more DVE. Being a primipara, being in latent phase at admission, having augmentation of labor, prolonged labor, being admitted with intact membranes, and vacuum delivery showed significant associations with frequent DVE. Frequency of DVE among laboring mothers is relatively high in the study area. The frequent DVE were mainly caused by healthcare provider's interventions to shorten the time of labor. Emphasis on training and monitoring the practice of healthcare givers would be helpful to mitigate this problem.

Reactor experiments on irradiation of two-phase lithium ceramics Li2TiO3/Li4SiO4 of various ratios

The design of future fusion reactors involves the production of tritium inside the breeder blanket. The most promising material for solid breeder blankets is a two-phase lithium ceramic containing orthosilicate Li4SiO4 (LOS) and metatitanate Li2TiO3 (LMT) of lithium in various proportions. Tritium is formed in lithium under neutron irradiation by the reaction 6Li(n,α)T. Further, this tritium is extracted from the blanket with a purge gas and returned to the fusion zone, realizing the concept of a closed fusion cycle.Irradiation under fission reactor conditions is still one of the few available methods for estimating the parameters of tritium generation and release from lithium-containing materials in the "in-situ" mode. This paper presents the results of experiments on neutron irradiation of two-phase lithium ceramics of various ratios (LOS + 35 mol. % LMT (pebble size 250–1250 μm), LOS + 35 mol. % LMT (pebble size 500–710 μm) and LOS + 25 mol. % LMT (pebble size 500–710 μm) at the WWR-K research reactor.Irradiation of each batch of samples lasted from 5 to 22 days. The experiments were carried out by the vacuum extraction method. This paper describes the main methodological aspects of the studies, namely the technical features of four irradiation campaigns, the sequence and scope of the studies. A comparison is also made of the initial sections of reactor experiments for all campaigns, where the reactor was sequentially brought to power, according to which the parameters of the Arrhenius dependence of the effective tritium diffusion coefficients were estimated.

Maternal complications and risk factors associated with assisted vaginal delivery

ObjectiveThis study aimed to elucidate the maternal complications and risk factors linked with assisted vaginal delivery.MethodsWe conducted a retrospective, descriptive analysis of hospital records, identifying 3500 cases of vaginal delivery between 2020 and 2022. Data encompassing demographics, complications from the vaginal delivery including post-partum haemorrhage, birth passage injuries, puerperal infection and other pertinent details were documented. Various critical factors, including the duration of the second stage of labor, maternal anemia, underlying maternal health conditions such as diabetes mellitus and hypertension, neonatal birth weight, maternal weight, the expertise of the attending surgeon, and the timing of deliveries were considered.ResultsThe rates for assisted vacuum and forceps delivery were 6.0% (211/3500 cases) and 0.3% (12/3500), respectively. Postpartum haemorrhage emerged as the predominant complication in vaginal deliveries, with a rate of 7.3% (256/3500; P < 0.001). Notably, postpartum haemorrhage had significant associations with gestational diabetes mellitus class A1 (adjusted odds ratio [AOR] 1.46; 95% confidence interval [CI] 1.01–2.11; P = 0.045), assisted vaginal delivery (AOR 5.11; 95% CI 1.30–20.1; P = 0.020), prolonged second stage of labour (AOR 2.68; 95% CI 1.09–6.58; P = 0.032), elevated maternal weight (71.4 ± 12.2 kg; AOR 1.02; 95% CI 1.01–1.03; P = 0.003) and neonates being large for their gestational age (AOR 3.02; 95% CI 1.23–7.43; P = 0.016).ConclusionsThe primary complication arising from assisted vaginal delivery was postpartum haemorrhage. Associated factors were a prolonged second stage of labour, foetal distress, large-for-gestational-age neonates and elevated maternal weight. Cervical and labial injuries correlated with neonates being large for their gestational age. Notably, puerperal infections were related to maternal anaemia (haematocrit levels < 33%).Clinical trial registrationThai Clinical Trials Registry: 20220126004.

Maternal and neonatal trauma during forceps and vacuum delivery must not be overlooked.

Maternal and neonatal trauma during forceps and vacuum delivery must not be overlooked.

Predictive factors for obstetric anal sphincter injury in primiparous women: systematic review and meta-analysis.

The primary objective was to perform a systematic review of predictive factors for obstetric anal sphincter injury (OASI) occurrence at first vaginal delivery, with the diagnosis made by ultrasound (US-OASI). The secondary objective was to report on incidence rates of sonographic anal sphincter (AS) trauma, including trauma that was not clinically reported at childbirth, among the studies providing data for our primary objective. We conducted a systematic search of MEDLINE, EMBASE, Web of Science, CINAHL, The Cochrane Library and ClinicalTrials.gov databases. Both observational cohort studies and interventional trials were eligible for inclusion. Study eligibility was assessed independently by two authors. Random-effects meta-analyses were performed to pool effect estimates from studies reporting on similar predictive factors. Summary odds ratio (OR) or mean difference (MD) is reported with 95% CI. Heterogeneity was assessed using the I2 statistic. Methodological quality was assessed using the Quality in Prognosis Studies tool. A total of 2805 records were screened and 21 met the inclusion criteria (16 prospective cohort studies, three retrospective cohort studies and two interventional non-randomized trials). Increasing gestational age at delivery (MD, 0.34 (95% CI, 0.04-0.64) weeks), shorter antepartum perineal body length (MD, -0.60 (95% CI, -1.09 to -0.11) cm), labor augmentation (OR, 1.81 (95% CI, 1.21-2.71)), instrumental delivery (OR, 2.13 (95% CI, 1.13-4.01)), in particular forceps extraction (OR, 3.56 (95% CI, 1.31-9.67)), shoulder dystocia (OR, 12.07 (95% CI, 1.06-137.60)), episiotomy use (OR, 1.85 (95% CI, 1.11-3.06)) and shorter episiotomy length (MD, -0.40 (95% CI, -0.75 to -0.05) cm) were associated with US-OASI. When pooling incidence rates, 26% (95% CI, 20-32%) of women who had a first vaginal delivery had US-OASI (20 studies; I2 = 88%). In studies reporting on both clinical and US-OASI rates, 20% (95% CI, 14-28%) of women had AS trauma on ultrasound that was not reported clinically at childbirth (16 studies; I2 = 90%). No differences were found in maternal age, body mass index, weight, subpubic arch angle, induction of labor, epidural analgesia, episiotomy angle, duration of first/second/active-second stages of labor, vacuum extraction, neonatal birth weight or head circumference between cases with and those without US-OASI. Antenatal perineal massage and use of an intrapartum pelvic floor muscle dilator did not affect the odds of US-OASI. Most (81%) studies were judged to be at high risk of bias in at least one domain and only four (19%) studies had an overall low risk of bias. Given the ultrasound evidence of structural damage to the AS in 26% of women following a first vaginal delivery, clinicians should have a low threshold of suspicion for the condition. This systematic review identified several predictive factors for this. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

EP25.06: Clinical and sonographic characteristics and outcome of vacuum extractions in occiput posterior fetuses: a retrospective cohort study

EP25.06: Clinical and sonographic characteristics and outcome of vacuum extractions in occiput posterior fetuses: a retrospective cohort study

Post Vaginal Delivery with Impending Silent Abdominal Catastrophe: A Case of Vernix Caseosa Peritonitis

Vernix caseosa peritonitis (VCP) is a rare condition previously thought to be a complication of Caesarean section caused by the spillage of amniotic fluid and or meconium into the maternal peritoneal cavity during operation.1 This triggered an inflammatory reaction symptom such as an acute abdomen. A total of 34 cases has been reported since 1976.2 Nine of the 10 cases reported have been diagnosed in postpartum period after uneventful Caesarean section and only three reported cases of antenatal leakage since in 1998.3 VCP following vaginal delivery was first reported in 2013, involving a 28 year old with one previous scar who developed acute abdomen symptoms as early as 3 hours post vacuum delivery, with initial diagnosis of possible uterine scar rupture.4 Here we report a case of VCP in a post spontaneous vaginal delivery who presented with impending catastrophe and survived the ordeal.

Comparison of practice vs theory model training for vacuum-assisted delivery: A randomized controlled trial

ObjectiveTo assess the effect of two modalities of simulation training on acquisition/retention of skills for performing operative vaginal delivery. DesignRandomized, controlled, single-centre study. SettingA tertiary referral hospital in Italy. ParticipantsTwenty residents from a single university programme and two young specialists. InterventionGroup 1 had an individual training session with a single senior specialist using a fixed simulator model. After the session, trainees watched a pre-recorded 1-h lecture on vacuum-assisted operative vaginal delivery. Group 1 repeated the simulator session using the same test after 8–12 weeks and 12 months. Group 2 watched the pre-recorded lecture then undertook the same sessions as Group 1. Video recordings of all test performances were evaluated by five specialists in a blinded manner. Main outcome measureEach procedure was evaluated using a Global Rating Scale (GRS), scored with 0–5 points for each item on an Objective Structured Assessment of Technical Skills (OSATS) dataset with seven items (total 35 points). OSATS were evaluated over time, compared for the whole population, and weighted for route and year of residency. The primary outcome was comparison of the effectiveness of training between the two groups based on year of residency by assessing videos of the baseline test and GRS for OSATS scores. The secondary outcome was overall retention of skills at 8–12 weeks and 12 months. ResultsTwenty-two participants were recruited and randomized to either Group 1 (n = 11) or Group 2 (n = 11). Five participants did not complete follow-up. The primary outcome of GRS for OSATS scores at time 0 differed significantly between groups for total GRS score, and ‘Call for help’ and ‘Explanation to woman and relatives’ item scores (p = 0.002 and p = 0.007, respectively). In a multiple linear regression analysis, OSATS scores were not independently influenced by year of residency. At 8–12-week follow-up, the ‘Call for help’ item score showed a significant improvement in Group 1 (p = 0.018), although this was not confirmed when year of residency was included as an independent variable. At 12-month follow-up, none of the item scores demonstrated a significant change (p = 0.033). Year of residency did not influence the difference between groups. One-way analysis of variance found significant differences between the groups for ‘Localization of the flexion point’ (p = 0.005), ‘Traction of vacuum cup’ (p = 0.039) and ‘Use of second hand of the operator’ (p = 0.009) item scores and total GRS score (p = 0.007). The values weighted by year of residency did not demonstrate any significant difference. The secondary outcomes evaluated all the candidates of both groups for retention of technical skills over time. A significant effect of time was found for total GRS score (p < 0.001) and OSATS item scores. ConclusionsIndependent of the sequence of theoretical teaching and simulation training, trainees demonstrated high retention – and, actually, improvement – of technical skills for operative vaginal delivery at 12-month follow-up.