Current Practice of Maternal-Fetal Medicine Specialists Regarding the Prevention and Management of Preterm Birth in Twin Gestations.

OBJECTIVE: To investigate the current practices of maternal-fetal medicine (MFM) specialists regarding the prevention and management of preterm birth (PTB) in twin pregnancies. METHODS: This was a cross-sectional study of Canadian MFM specialists. Participants responded to an anonymous survey regarding the prevention and management of PTB in twins, including lifestyle and gestational weight gain recommendations, cervical length screening, PTB prevention, and labour and delivery practices. RESULTS: Of 137 MFM specialists surveyed, 95 (69%) responded. Most MFM specialists recommend against activity restriction (77.9%), avoidance of sexual activity (96.7%), routine progesterone (97.8%), routine prophylactic cerclage (98.9%), and routine administration of antenatal corticosteroids (95.6%). There were considerable inconsistencies with respect to gestational weight gain management. Despite lack of support by guidelines, most MFM specialists reported using routine cervical length screening (97.8%) and progesterone for short cervix (92.3%). Over half (52.7%) of MFM specialists recommend cervical cerclage when the cervix is <15mm. In cases of PTB, most MFM specialists recommend vaginal delivery when twins are in vertex presentation (63%-75%). MFM specialists are less likely to recommend vaginal delivery when twin B is non-vertex (35%-41%). CONCLUSION: There is a considerable variation among MFM specialists regarding the prevention and management of PTB in twins, and the practice of many MFM specialists differs from that recommended by professional societies' guidelines. These findings underscore the necessity for high-quality studies and up-to-date recommendations.

Counselling Patients for Trial of Labour after Cesarean (TOLAC) and Invasive Placentation: Are We Missing the Mark? The Importance of Local Data and Informed Choice.

OBJECTIVE: Rates of cesarean delivery are increasing, and these procedures carry potential complications, like the risk of invasive placentation, which increases with each cesarean. A trial of labour after cesarean (TOLAC) is a viable option for patients; however, it has been associated with uterine rupture, a complication with maternal and fetal risks. To better counsel patients considering TOLAC, we aimed to determine local uterine rupture rates and maternal and neonatal outcomes with TOLAC and compare these with outcomes related to invasive placentation. METHODS: A 4-year retrospective chart review was conducted at our tertiary centre of all patients with a history of a previous cesarean delivery. We assessed rates of TOLAC, vaginal delivery after cesarean (VBAC), and uterine rupture, as well as maternal and neonatal outcomes associated with invasive placentation. Cases of uterine rupture from 1988 to the present were also reviewed, and their outcomes were compared with those of invasive placentation. RESULTS: Our uterine rupture rate was 0.44% and VBAC rate was 73.8%. We identified 8 cases of uterine rupture since 1988 and 67 invasive placentas during the 4-year chart review. Invasive placentation was associated with a significantly increased risk of neonatal respiratory morbidity, hysterectomy, maternal complications, and longer length of maternal hospital stay when compared with uterine rupture. CONCLUSION: While uterine rupture remains a potential complication of TOLAC, it is rare with overall excellent maternal and neonatal outcomes. Invasive placentation, the risk of which increases with cesarean delivery, carries potentially higher complication rates than uterine rupture. Local complication data is important for individual sites offering TOLAC. The implications of invasive placentation cannot be overlooked when counselling patients considering TOLAC.

Guideline No. 398: Progesterone for Prevention of Spontaneous Preterm Birth.

OBJECTIVES: To assess the benefits and risks of progesterone therapy for women at increased risk of spontaneous preterm birth (SPB) and to make recommendations for the use of progesterone to reduce the risk of SPB and improve postnatal outcomes. OPTIONS: To administer or withhold progesterone therapy for women deemed to be at high risk of SPB. OUTCOMES: Preterm birth, neonatal morbidity and mortality, and postnatal outcomes including neurodevelopmental outcomes. INTENDED USERS: Maternity care providers, including midwives, family physicians, and obstetricians. TARGET POPULATION: Pregnant women at increased risk of SPB. EVIDENCE: Medline, PubMed, EMBASE, and the Cochrane Library were searched from inception to October 2018 for medical subject heading (MeSH) terms and keywords related to pregnancy, preterm birth, previous preterm birth, short cervix, uterine anomalies, cervical conization, neonatal morbidity and mortality, and postnatal outcomes. This document represents an abstraction of the evidence rather than a methodological review. VALIDATION METHODS: This guideline was reviewed by the Maternal-Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and approved by the SOGC Board of Directors. BENEFITS, HARMS, AND/OR COSTS: Therapy with progesterone significantly reduces the risk of SPB in a subpopulation of women at increased risk. Although this therapy entails a cost to the woman in addition to the discomfort associated with its use, no other adverse effects to the mother or the baby have been identified. SUMMARY STATEMENTS (GRADE RATINGS IN PARENTHESES): RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

COVID-19 during pregnancy: an overview of maternal characteristics, clinical symptoms, maternal and neonatal outcomes of 10,996 cases described in 15 countries.

The objective of this review was to identify the most significant studies reporting on COVID-19 during pregnancy and to provide an overview of SARS-CoV-2 infection in pregnant women and perinatal outcomes. Eligibility criteria included all reports, reviews; case series with more than 100 individuals and that reported at least three of the following: maternal characteristics, maternal COVID-19 clinical presentation, pregnancy outcomes, maternal outcomes and/or neonatal/perinatal outcomes. We included eight studies that met the inclusion criteria, representing 10,966 cases distributed in 15 countries around the world until July 20, 2020. The results of our review demonstrate that the maternal characteristics, clinical symptoms, maternal and neonatal outcomes almost 11,000 cases of COVID-19 and pregnancy described in 15 different countries are not worse or different from the general population. We suggest that pregnant women are not more affected by the respiratory complications of COVID-19, when compared to the outcomes described in the general population. We also suggest that the important gestational shift Th1-Th2 immune response, known as a potential contributor to the severity in cases of viral infections during pregnancy, are counter-regulated by the enhanced-pregnancy-induced ACE2-Ang-(1-7) axis. Moreover, the relatively small number of reported cases during pregnancy does not allow us to affirm that COVID-19 is more aggressive during pregnancy. Conversely, we also suggest, that down-regulation of ACE2 receptors induced by SARS-CoV-2 cell entry might have been detrimental in subjects with pre-existing ACE2 deficiency associated with pregnancy. This association might explain the worse perinatal outcomes described in the literature.

Sonographic lower uterine segment thickness after prior cesarean section to predict uterine rupture: A systematic review and meta-analysis.

INTRODUCTION: Cesarean section rates are increasing with a decrease in the rate of trial of labor after cesarean section. The objective of this study was to systematically review the predictive characteristics of sonographic measurement of lower uterine segment thickness for uterine rupture during labor. MATERIAL AND METHODS: The review was carried out in agreement with PRISMA and SEDATE guidelines. MEDLINE, EMBASE, ClinicalTrials.gov and Cochrane Library were searched from 1990 until November 2018. Quality of included studies was assessed using the QUADAS-2 tool. Data were extracted to construct 2 × 2 tables from each study comparing ultrasound measurement with uterine defect at time of delivery. The data were plotted as a summary receiver-operating characteristic (SROC) curve using the hierarchical SROC model. RESULTS: Twenty-eight observational cohort studies met the selection criteria for inclusion. Sonographic lower uterine segment thickness was measured at a gestational age of 36-40 weeks in women with a previous cesarean section. The risk of bias and concerns regarding applicability were low among most studies. The sonographic measurement was correlated with either delivery outcome or lower uterine segment thickness at the time of repeat cesarean section. The cut-off value for lower uterine segment thickness ranged from 1.5 to 4.05 mm across all studies. An association between thin lower uterine segment measurement and uterine dehiscence and uterine rupture was shown in 27 and four studies, respectively. Nineteen studies were included in a meta-analysis with a subgroup analysis by ultrasound methodology. In the subgroup using the ultrasound methodology associated with uterine rupture, the cut-off value is more precise (2.0-3.65 mm) among these 12 studies. There were 18 cases (1.0%) of uterine rupture, 120 (6.6%) of uterine dehiscence and 1674 (92.4%) women with no uterine defect. The SROC curve showed a sensitivity of 0.88 (95% CI 0.83-0.92) and specificity of 0.77 (95% CI 0.70-0.83). The negative likelihood ratio was 0.11 (95% CI 0.08-0.16) and the diagnostic odds ratio was 34.0 (95% CI 18.2-63.5). CONCLUSIONS: Lower uterine segment thickness >3.65 mm, measured using a standardized ultrasound technique, is associated with a lower likelihood of uterine rupture.

Update on uterine tachysystole.

Uterine tachysystole (TS) is a potentially significant intrapartum complication seen most commonly in induced or augmented labors but may also occur in women with spontaneous labor. When it occurs, maternal and perinatal complications can arise if not identified and managed promptly by obstetric care providers. Over recent years, new definitions of the condition have facilitated further research into the field, which has been synthesized to inform clinical management guidelines and protocols. We propose a set of recommendations pertaining to TS in line with contemporary evidence and obstetric practice.

No. 240-Cytomegalovirus Infection in Pregnancy.

OBJECTIVES: To review the principles of prenatal diagnosis of congenital cytomegalovirus (CMV) infection and to describe the outcomes of the affected pregnancies. OUTCOMES: Effective management of fetal infection following primary and secondary maternal CMV infection during pregnancy. Neonatal signs include intrauterine growth restriction (IUGR), microcephaly, hepatosplenomegaly, petechiae, jaundice, chorioretinitis, thrombocytopenia and anemia, and long-term sequelae consist of sensorineural hearing loss, mental retardation, delay of psychomotor development, and visual impairment. These guidelines provide a framework for diagnosis and management of suspected CMV infections. EVIDENCE: Medline was searched for articles published in English from 1966 to 2009, using appropriate controlled vocabulary (congenital CMV infection) and key words (intrauterine growth restriction, microcephaly). Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. Searches were updated on a regular basis and incorporated into the guideline. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. RECOMMENDATIONS: The quality of evidence reported in this document has been assessed using the evaluation of evidence criteria in the Report of the Canadian Task Force on Preventive Health Care (Table 1).

Management and Outcome of Reduced Fetal Movements-is Ultrasound Necessary?

OBJECTIVE: To review the management and outcome of pregnancies of women presenting to obstetrical triage with decreased fetal movements (DFM). STUDY DESIGN: A retrospective review of women presenting with DFMs to two large Canadian obstetrical centres with a combined 9490 deliveries per year. The charts were reviewed for compliance with the Canadian guidelines for demographics (age, parity, GA, comorbidities, etc.), pregnancy management (admission vs. discharge, need to deliver), and pregnancy outcomes (mortality, morbidity, GA at delivery, Apgar scores, etc.). Patients who did not comply with the Canadian guidelines (requiring the patient to count six movements within two hours) were not excluded. RESULTS: The charts of 579 patients who self-reported DFMs between January 2012 and December 2012 were reviewed. The distribution of ages was between 18 and 47 year old. The majority of these patients had no comorbidities (454/579). A significant minority of patients had FM in the triage area (231/579). The Canadian guidelines were interpreted differently in the two centres. In one (level 3), the protocol was to have a biophysical profile (BPP) on all patients prior to discharge, whereas in the other (level 2), only patients with a non-reactive non-stress test (NST) and/or oligohydramnios or intrauterine growth restriction (IUGR) underwent a BPP. All patients had an evaluation by an RN and MD and had a NST on arrival. A combination of NST and BPP was performed on 235/579. The frequency of DFM was 6.1% (level 3 centre: 5.6%, level 2 centre: 7.8%). There were 8 stillbirths on arrival. The 187 patients who had a reactive NST and a normal BPP and were sent home did not have a single stillbirth within 2 weeks. In the level 3 centre, 19 patients were sent home without a BPP and one had a stillbirth within 2 days (5%); in the level 2 hospital, there was only one stillbirth among the NST-only group (0.35%). There were 65 admissions; 46 of them (71%) were delivered, and 50% of them had a Caesarean delivery (baseline around 30%). CONCLUSIONS: This is the first study looking at the performance of the Canadian guidelines of 2007. We found that the DFM rate was compatible with the literature (6.1% vs. 5%). The frequency of stillbirth on arrival was 1.4% (8/579). Patients discharged after normal NST and BPP did extremely well (no stillbirths), whereas those admitted following DFM had a relatively high Caesarean delivery rate (50%). This study was not designed to address changes in stillbirth rate, but it outlines the patients who experience DFM and their eventual outcomes.

No. 274-Management of Varicella Infection (Chickenpox) in Pregnancy.

OBJECTIVE: To review the existing data regarding varicella zoster virus infection (chickenpox) in pregnancy, interventions to reduce maternal complications and fetal infection, and antepartum and peripartum management . METHODS: The maternal and fetal outcomes in varicella zoster infection were reviewed, as well as the benefit of the different treatment modalities in altering maternal and fetal sequelae. EVIDENCE: Medline was searched for articles and clinical guidelines published in English between January 1970 and November 2010. VALUES: The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table).

No. 281-Classification of Caesarean Sections in Canada: The Modified Robson Criteria.

OBJECTIVE: To advocate for the use of a common classification system for Caesarean section across Canada. OPTIONS: A variety of clinical parameters for classification were considered. OUTCOMES: Consideration of a common system for classifying Caesarean section. EVIDENCE: Studies published in English from 1976 to December 2011 were retrieved through searches of Medline and PubMed, using appropriate controlled vocabulary and key words (Caesarean section, vaginal birth after Caesarean, classification) . Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Grey (unpublished) literature was identified through searching the web sites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and the web sites of national and international medical specialty societies . VALUES: The studies reviewed were classified according to criteria described by the Canadian Task Force on Preventive Health Care, and the recommendation for practice ranked according to this classification (Table 1). SPONSORS: The Society of Obstetricians and Gynaecologists of Canada. RECOMMENDATION: Modified Robson criteria should be used to enable comparison of Caesarean section rates and indications (III-B).

Do Early Fetal Measurements and Nuchal Translucency Correlate With Term Birth Weight?

OBJECTIVE: Traditionally, physiological variation in fetal weight is believed to emerge during the latter half of pregnancy. Although recent evidence suggests that crown-rump length (CRL) and nuchal translucency (NT) measured at 11-14 weeks correlate with abnormal fetal growth, findings have been limited by dating accuracy in spontaneous gestations. Therefore, we sought to determine whether CRL or NT measurements correlated with term birth weight (BW) or BW ratio in a cohort of IVF pregnancies, in which the date of conception is precisely known. METHODS: This retrospective cohort study included 227 term, singleton IVF pregnancies. Subjects were included if they had an early first-trimester ultrasound examination and subsequent nuchal translucency (NT) screening. The difference between the measured and the expected CRL and the biparietal diameter (BPD) and NT measurement were calculated and correlated with the actual term BW or BW ratio. The BW ratio was calculated using the actual BW and the expected BW for GA. RESULTS: The difference between measured and expected mid-first-trimester CRL, and the BPD at NT assessment, correlated with BW ratio at delivery (rSpearman = 0.15, P = 0.023 and rSpearman = 0.27, P < 0.001, respectively). Absolute NT measurements and NT percentiles (adjusted for CRL) correlated with BW ratio at delivery (rSpearman = 0.18, r = 0.14, and P = 0.005 and 0.038, respectively). CONCLUSION: In this well-dated IVF population, we report a significant correlation between BW ratio and first-trimester CRL, BPD, and NT measurements. These findings support the hypothesis that physiological variation in BW can be reflected by variation in first-trimester fetal measurements.

Venous thromboembolism in obese pregnant women: approach to diagnosis and management.

Venous thromboembolism (VTE) remains among the leading causes of maternal mortality in the developed world, presenting variably as deep vein thrombosis (DVT), pulmonary embolism (PE) or cerebral vein thrombosis (CVT), among others. Obesity in particular has been recognized as the principal contributing factor to the risk of VTE in pregnancy and with the global increase in the rates of obesity affecting reproductive age women, heightened awareness of the risk and consequences of VTE in this population are vital. Thus, prophylaxis, diagnosis and treatment of VTE in the obese gravida are discussed.

Current practices in the prediction and prevention of preterm birth in patients with higher-order multiple gestations.

OBJECTIVE: We sought to determine the interventions utilized by maternal-fetal medicine specialists in the prediction and prevention of preterm labor in higher-order multiple (HOM) gestations. STUDY DESIGN: Online questionnaires and email surveys were sent to all the maternal-fetal medicine specialists in Canada (n=122). Questionnaire items included interventions physicians routinely recommended for HOM gestations including: (1) bed rest; (2) cervical length measurement on transvaginal ultrasound; (3) corticosteroids use; (4) cerclage; and (5) tocolytic therapy. RESULTS: Response rate was 66% (81/122), with 68% of respondents in practice for >10 years. Of physicians, 91% did not routinely recommend bed rest (95% confidence interval [CI], 84.7-97.2). In all, 82% (95% CI, 73.63-90.4%) recommended routine cervical length assessment with 32.3% (95% CI, 20.7-43.2) and 37.1% (95% CI, 25.3-48.6) of this group suggesting assessment at 16-18 and 19-21 weeks, respectively. Frequency of assessment varied from biweekly (53.3%; 95% CI, 40.9-65.0), to monthly (23.3%; 95% CI, 12.8-33.1), to a single measurement repeated only if abnormal (12.5%; 95% CI, 4.5-20.8). In all, 28% (95% CI, 18.2-37.8) recommended routine administration of corticosteroids for lung maturation. Timing of administration varied, with 24% initiating steroids between 24-26 weeks, 59% between 27-28 weeks, and 17% after 28 weeks. None reported routine cerclage placement. However, 71% (95% CI, 61.1-80.8) would perform cerclage based on history or ultrasound. Of respondents, 81% (95% CI, 72.4-89.5) would consider using tocolytic agents for threatened preterm labor including calcium channel blockers (94%), nonsteroidal antiinflammatory drugs (5%), and nitroglycerin transdermal patch (24%). CONCLUSION: The variable practice guidelines and paucity of data for management of HOM pregnancy places the onus on individual practitioners to develop their own management schemes. This results in heterogeneous management, which is based on conflicting international guidelines, studies, expert opinion, or past experience.

Carbetocin at Cesarean delivery for labour arrest: a sequential allocation trial to determine the effective dose.

PURPOSE: The aim of this study was to estimate the effective dose 90% (ED90) of carbetocin to provide adequate uterine tone at Cesarean delivery (CD) for labour arrest. METHODS: We conducted a double-blind dose-finding study of carbetocin using a biased-coin up-and-down design in women undergoing CD for labour arrest under epidural anesthesia. Forty healthy term pregnant women who had received at least three hours of oxytocin infusion during labour were recruited for the study. Carbetocin was administered intravenously upon delivery of the anterior shoulder of the fetus. The first patient received 20 µg, and the dose for the subsequent patient was determined according to the response of the previous patient as per the biased-coin allocation scheme using increments or decrements of 20 µg (maximum 140 µg). Uterine tone was assessed by the obstetrician and rated as satisfactory or unsatisfactory throughout the intraoperative period. The primary outcome was satisfactory uterine tone with no need for additional uterotonic drugs intraoperatively. Secondary outcomes included use of additional uterotonic drugs postoperatively in the first 24 hr, estimated blood loss, and adverse effects. RESULTS: The ED90 of carbetocin to produce adequate uterine tone was estimated at 121 µg (95% confidence interval [CI]: 111 to 130; 99% CI: 108 to 133) using the truncated Dixon and Mood (DM) method. The isotonic estimator of ED90 was 140 µg; however, the observed response rate across all doses was < 90%. Also, the 95% CI of the DM estimator is likely to have lower than expected coverage, while the 99% CI may have about 90% coverage. Therefore, these results should be interpreted with caution. The overall median (range) estimated blood loss was 1,014 (104-2,436) mL. The overall incidence of hypotension and tachycardia were 45% and 57.5%, respectively. At a dose of 140 µg, the incidence of tachycardia and intraoperative arrhythmias was 76% and 14%, respectively. CONCLUSION: The ED90 of carbetocin at CD for labour arrest, as determined in our study, should be interpreted with caution since it may be underestimated. This dose is higher than the currently recommended dose of 100 µg at elective CD and should not be used routinely given the uncertainty regarding its efficacy and the high incidence of arrhythmias at higher doses. This trial was registered at ClinicalTrials.gov, number: NCT01725243.

Guidelines for the Management of a Pregnant Trauma Patient.

OBJECTIVE: Physical trauma affects 1 in 12 pregnant women and has a major impact on maternal mortality and morbidity and on pregnancy outcome. A multidisciplinary approach is warranted to optimize outcome for both the mother and her fetus. The aim of this document is to provide the obstetric care provider with an evidence-based systematic approach to the pregnant trauma patient. OUTCOMES: Significant health and economic outcomes considered in comparing alternative practices. EVIDENCE: Published literature was retrieved through searches of Medline, CINAHL, and The Cochrane Library from October 2007 to September 2013 using appropriate controlled vocabulary (e.g., pregnancy, Cesarean section, hypotension, domestic violence, shock) and key words (e.g., trauma, perimortem Cesarean, Kleihauer-Betke, supine hypotension, electrical shock). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English between January 1968 and September 2013. Searches were updated on a regular basis and incorporated in the guideline to February 2014. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: This guideline is expected to facilitate optimal and uniform care for pregnancies complicated by trauma. Summary Statement Specific traumatic injuries At this time, there is insufficient evidence to support the practice of disabling air bags for pregnant women. (III) Recommendations Primary survey 1. Every female of reproductive age with significant injuries should be considered pregnant until proven otherwise by a definitive pregnancy test or ultrasound scan. (III-C) 2. A nasogastric tube should be inserted in a semiconscious or unconscious injured pregnant woman to prevent aspiration of acidic gastric content. (III-C) 3. Oxygen supplementation should be given to maintain maternal oxygen saturation > 95% to ensure adequate fetal oxygenation. (II-1B) 4. If needed, a thoracostomy tube should be inserted in an injured pregnant woman 1 or 2 intercostal spaces higher than usual. (III-C) 5. Two large bore (14 to 16 gauge) intravenous lines should be placed in a seriously injured pregnant woman. (III-C) 6. Because of their adverse effect on uteroplacental perfusion, vasopressors in pregnant women should be used only for intractable hypotension that is unresponsive to fluid resuscitation. (II-3B) 7. After mid-pregnancy, the gravid uterus should be moved off the inferior vena cava to increase venous return and cardiac output in the acutely injured pregnant woman. This may be achieved by manual displacement of the uterus or left lateral tilt. Care should be taken to secure the spinal cord when using left lateral tilt. (II-1B) 8. To avoid rhesus D (Rh) alloimmunization in Rh-negative mothers, O-negative blood should be transfused when needed until cross-matched blood becomes available. (I-A) 9. The abdominal portion of military anti-shock trousers should not be inflated on a pregnant woman because this may reduce placental perfusion. (II-3B) Transfer to health care facility 10. Transfer or transport to a maternity facility (triage of a labour and delivery unit) is advocated when injuries are neither life- nor limb-threatening and the fetus is viable (≥ 23 weeks), and to the emergency room when the fetus is under 23 weeks' gestational age or considered to be non-viable. When the injury is major, the patient should be transferred or transported to the trauma unit or emergency room, regardless of gestational age. (III-B) 11. When the severity of injury is undetermined or when the gestational age is uncertain, the patient should be evaluated in the trauma unit or emergency room to rule out major injuries. (III-C) Evaluation of a pregnant trauma patient in the emergency room 12. In cases of major trauma, the assessment, stabilization, and care of the pregnant women is the first priority; then, if the fetus is viable (≥ 23 weeks), fetal heart rate auscultation and fetal monitoring can be initiated and an obstetrical consultation obtained as soon as feasible. (II-3B) 13. In pregnant women with a viable fetus (≥ 23 weeks) and suspected uterine contractions, placental abruption, or traumatic uterine rupture, urgent obstetrical consultation is recommended. (II-3B) 14. In cases of vaginal bleeding at or after 23 weeks, speculum or digital vaginal examination should be deferred until placenta previa is excluded by a prior or current ultrasound scan. (III-C) Adjunctive tests for maternal assessment 15. Radiographic studies indicated for maternal evaluation including abdominal computed tomography should not be deferred or delayed due to concerns regarding fetal exposure to radiation. (II-2B) 16. Use of gadolinium-based contrast agents can be considered when maternal benefit outweighs potential fetal risks. (III-C) 17. In addition to the routine blood tests, a pregnant trauma patient should have a coagulation panel including fibrinogen. (III-C) 18. Focused abdominal sonography for trauma should be considered for detection of intraperitoneal bleeding in pregnant trauma patients. (II-3B) 19. Abdominal computed tomography may be considered as an alternative to diagnostic peritoneal lavage or open lavage when intra-abdominal bleeding is suspected. (III-C) Fetal assessment 20. All pregnant trauma patients with a viable pregnancy (≥ 23 weeks) should undergo electronic fetal monitoring for at least 4 hours. (II-3B) 21. Pregnant trauma patients (≥ 23 weeks) with adverse factors including uterine tenderness, significant abdominal pain, vaginal bleeding, sustained contractions (> 1/10 min), rupture of the membranes, atypical or abnormal fetal heart rate pattern, high risk mechanism of injury, or serum fibrinogen < 200 mg/dL should be admitted for observation for 24 hours. (III-B) 22. Anti-D immunoglobulin should be given to all rhesus D-negative pregnant trauma patients. (III-B) 23. In Rh-negative pregnant trauma patients, quantification of maternal-fetal hemorrhage by tests such as Kleihauer-Betke should be done to determine the need for additional doses of anti-D immunoglobulin. (III-B) 24. An urgent obstetrical ultrasound scan should be undertaken when the gestational age is undetermined and need for delivery is anticipated. (III-C) 25. All pregnant trauma patients with a viable pregnancy who are admitted for fetal monitoring for greater than 4 hours should have an obstetrical ultrasound prior to discharge from hospital. (III-C) 26. Fetal well-being should be carefully documented in cases involving violence, especially for legal purposes. (III-C) Obstetrical complications of trauma 27. Management of suspected placental abruption should not be delayed pending confirmation by ultrasonography as ultrasound is not a sensitive tool for its diagnosis. (II-3D) Specific traumatic injuries 28. Tetanus vaccination is safe in pregnancy and should be given when indicated. (II-3B) 29. Every woman who sustains trauma should be questioned specifically about domestic or intimate partner violence. (II-3B) 30. During prenatal visits, the caregiver should emphasize the importance of wearing seatbelts properly at all times. (II-2B) Perimortem Caesarean section 31. A Caesarean section should be performed for viable pregnancies (≥ 23 weeks) no later than 4 minutes (when possible) following maternal cardiac arrest to aid with maternal resuscitation and fetal salvage. (III-B).

Objectif : Une femme enceinte sur 12 en vient à subir des traumatismes physiques et ceux-ci exercent des effets importants sur la mortalité et la morbidité maternelles, ainsi que sur l'issue de la grossesse. La mise en œuvre d'une approche multidisciplinaire s'avère justifiée pour assurer l'optimisation des issues, et ce, tant pour la mère que pour son fœtus. Le présent document a pour but d'offrir, aux fournisseurs de soins obstétricaux, une approche systématique factuelle qu'ils pourront utiliser pour assurer la prise en charge des patientes enceintes ayant subi un traumatisme. Issues : Issues sanitaires et économiques considérables, par comparaison avec les pratiques de rechange. Résultats : La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans Medline, CINAHL et The Cochrane Library entre octobre 2007 et septembre 2013 au moyen d'un vocabulaire contrôlé (« pregnancy ¼, « Cesarean section ¼, « hypotension ¼, « domestic violence ¼, « shock ¼) et de mots clés (« trauma ¼, « perimortem Cesarean ¼, « Kleihauer-Betke ¼, « supine hypotension ¼, « electrical shock ¼) appropriés. Les résultats ont été restreints aux analyses systématiques, aux études observationnelles et aux essais comparatifs randomisés / essais cliniques comparatifs publiés en anglais entre janvier 1968 et septembre 2013. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en février 2014. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales. Valeurs : La qualité des résultats a été évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs (Tableau). Avantages, désavantages et coûts : Nous nous attendons à ce que la présente directive clinique facilite l'offre de soins optimaux et uniformes dans les cas de grossesse compliquée par un traumatisme. Déclaration sommaireLésions traumatiques particulières Pour l'instant, nous ne disposons pas de données probantes suffisantes pour soutenir la désactivation des coussins gonflables dans le cas des femmes enceintes. (III) RecommandationsExamen primaire 1. La présence d'une grossesse devrait être présumée chez toutes les femmes en âge de procréer ayant subi des blessures considérables, jusqu'à ce que le contraire ait été prouvé au moyen d'une échographie ou d'un test de grossesse définitif. (III-C) 2. Chez les femmes enceintes blessées inconscientes ou à demi conscientes, une sonde nasogastrique devrait être insérée afin de prévenir l'aspiration de contenu gastrique acide. (III-C) 3. Une oxygénothérapie devrait être mise en œuvre pour garantir le maintien d'une saturation maternelle en oxygène > 95 %, de façon à assurer une oxygénation fœtale adéquate. (II-1B) 4. Chez les femmes enceintes blessées, l'insertion d'une sonde de thoracostomie (à un endroit se situant à un ou deux espaces intercostaux de plus que d'habitude) pourrait être envisagée, au besoin. (III-C) 5. Chez les femmes enceintes gravement blessées, deux lignes intraveineuses de gros calibre (14-16) devraient être mises en place. (III-C) 6. En raison des effets indésirables qu'ils exercent sur la perfusion utéroplacentaire chez les femmes enceintes, les vasopresseurs ne devraient être utilisés qu'en présence d'une hypotension réfractaire qui ne réagit pas à la réanimation liquidienne. (II-3B) 7. Chez les femmes enceintes gravement blessées qui ont passé le cap de la mi-grossesse, l'utérus gravide devrait être repositionné de façon à ce qu'il ne comprime plus la veine cave inférieure, et ce, dans le but d'accroître le retour veineux et le débit cardiaque. Ce repositionnement peut être obtenu en déplaçant l'utérus manuellement ou en plaçant la patiente en position latérale gauche (en s'assurant alors d'immobiliser la moelle épinière de la patiente au préalable). (II-1B) 8. Pour prévenir l'allo-immunisation rhésus D chez les femmes Rh négatives, du sang O négatif devrait être transfusé, au besoin, jusqu'à ce que du sang provenant d'un donneur compatible soit obtenu. (I-A) 9. La partie abdominale du pantalon pneumatique hypotenseur ne devrait pas être gonflée en présence d'une grossesse, car cela pourrait atténuer la perfusion placentaire. (II-3B) Transfert vers un établissement de santé 10. Le transfert vers un service de maternité (service de triage d'une unité de travail et d'accouchement) est recommandé lorsque la patiente en question ne présente pas de blessures potentiellement mortelles ou pouvant mener à la perte d'un membre et lorsque le fœtus est viable (≥ 23 semaines); le transfert vers une salle des urgences est recommandé lorsque le fœtus n'a pas encore atteint l'âge gestationnel de 23 semaines ou lorsqu'il n'est pas considéré comme étant viable. En présence d'un traumatisme majeur, la patiente devrait être transférée ou transportée vers une unité de traumatologie ou une salle des urgences, sans égard à l'âge gestationnel. (III-B) 11. Lorsque la gravité du traumatisme est indéterminée ou lorsque l'âge gestationnel est incertain, la patiente devrait faire l'objet d'une évaluation menée dans une unité de traumatologie ou une salle des urgences en vue d'écarter la présence de blessures majeures. (III-C) Évaluation, au sein d'une salle des urgences, d'une patiente enceinte ayant subi un traumatisme 12. En présence d'un traumatisme majeur, la priorité doit être accordée à l'évaluation, à la stabilisation et à la prise en charge de la femme enceinte; par la suite, lorsque le fœtus est viable (≥ 23 semaines), l'auscultation de la fréquence cardiaque fœtale et un monitorage fœtal peuvent être mis en œuvre. De plus, une consultation en obstétrique devrait être obtenue dès que possible. (II-3B) 13. La tenue d'une consultation d'urgence en obstétrique est recommandée en ce qui concerne les femmes enceintes dont le fœtus est viable (≥ 23 semaines) et chez qui l'on soupçonne la présence de contractions utérines, d'un décollement placentaire ou d'une rupture utérine traumatique. (II-3B) 14. En présence de saignements vaginaux à 23 semaines ou par la suite, la tenue d'un examen vaginal au moyen d'un spéculum ou des doigts devrait être reportée jusqu'à ce que la présence d'un placenta praevia ait été écartée par échographie (préalable ou actuelle). (III-C) Tests d'appoint dans le cadre de l'évaluation maternelle 15. Les études de radiographie nécessaires aux fins de l'évaluation maternelle (dont la tomodensitométrie abdominale) ne devraient pas être retardées ni reportées en raison de préoccupations à l'égard de l'exposition du fœtus à des rayonnements. (II-2B) 16. L'utilisation de produits de contraste à base de gadolinium peut être envisagée lorsque les avantages maternels l'emportent sur les risques fœtaux potentiels. (III-C) 17. En plus des tests sanguins qui sont régulièrement menés dans le cadre de l'évaluation des patientes enceintes ayant subi un traumatisme, un profil de coagulation (comprenant la mesure du taux de fibrinogène) devrait être obtenu. (III-C) 18. Chez les patientes enceintes ayant subi un traumatisme, la tenue d'une échographie abdominale ciblée pour l'identification de traumatismes devrait être envisagée aux fins de la détection des saignements intrapéritonéaux. (II-3B) 19. Lorsque la présence de saignements intra-abdominaux est soupçonnée, la tomodensitométrie abdominale pourrait constituer une solution de rechange au lavage péritonéal diagnostique ou au lavage ouvert. (III-C) Évaluation fœtale 20. Toutes les patientes enceintes ayant subi un traumatisme qui présentent une grossesse viable (≥ 23 semaines) devraient faire l'objet d'un monitorage fœtal électronique pendant au moins 4 heures. (II-3B) 21. Les patientes enceintes ayant subi un traumatisme (≥ 23 semaines) qui présentent des facteurs indésirables (dont la sensibilité utérine, des douleurs abdominales considérables, des saignements vaginaux, des contractions soutenues [> 1/10 min], la rupture des membranes, un profil de fréquence cardiaque fœtale atypique ou anormal, un mécanisme de blessure à risque élevé ou un taux sérique de fibrinogène < 200 mg/dl) devraient être hospitalisées pour une période d'observation de 24 heures. (III-B) 22. De l'immunoglobuline anti-D devrait être administrée à toutes les patientes enceintes Rh négatives ayant subi un traumatisme. (III-B) 23. Chez les patientes enceintes Rh négatives ayant subi un traumatisme, l'hémorragie fœtomaternelle devrait être quantifiée au moyen de mesures telles que le test de Kleihauer-Betke, et ce, dans le but de déterminer la nécessité de procéder à l'administration de doses additionnelles d'immunoglobuline anti-D. (III-B) 24. Une échographie obstétricale devrait être menée d'urgence lorsque l'âge gestationnel est indéterminé et que la nécessité de procéder à l'accouchement est anticipée. (III-C) 25. Toutes les patientes enceintes ayant subi un traumatisme qui présentent une grossesse viable et qui sont hospitalisées aux fins de la tenue d'un monitorage fœtal pendant plus de 4 heures devraient faire l'objet d'une échographie obstétricale avant d'obtenir leur congé de l'hôpital. (III-C) 26. Il est important de disposer, particulièrement à des fins juridiques, d'une documentation rigoureuse du bien-être fœtal dans les cas mettant en cause de la violence. (III-C) Complications obstétricales du traumatisme 27. La prise en charge de la présence soupçonnée d'un décollement placentaire ne devrait pas être différée jusqu'à l'obtention d'une confirmation par échographie; l'échographie ne dispose pas de la sensibilité requise pour l'établissement d'undiagnostic de décollement placentaire. (II-3D) Lésions traumatiques particulières 28. La vaccination antitétanique est sûre pendant la grossesse et devrait être administrée, au besoin. (II-3B) 29. Toutes les femmes qui subissent un traumatisme devraient faire l'objet de questions visant particulièrement la violence familiale ou conjugale. (II-3B) 30. Dans le cadre des consultations prénatales, le fournisseur de soins devrait souligner l'importance du port de la ceinture de sécurité de façon adéquate, en tout temps. (II-2B) Césarienne péri-mortem 31. En présence d'une grossesse viable (≥ 23 semaines), la tenue d'une césarienne est recommandée au plus tard 4 minutes (dans la mesure du possible) à la suite de l'arrêt cardiaque chez la mère, et ce, en vue de faciliter la réanimation maternelle et le sauvetage du fœtus. (III-B).

Maternal Obesity Class as a Predictor of Induction Failure: A Practical Risk Assessment Tool.

OBJECTIVE: To assess the impact of body mass index (BMI) on the rate of cesarean section (rCS) in induction of labor (IOL). STUDY DESIGN: A total of 7,543 singleton term pregnancies undergoing IOL (cervical dilatation at admission, CDA ≤ 3 cm) were divided according to BMI: underweight (n = 325); normal weight (NW) (n = 4,633); overweight (OW) (n = 1,610); and obese (n = 975). Age, parity, macrosomia, gestational age (GA), gestational weight gain (GWG), CDA, and IOL indications were considered. RESULTS: A higher rate of macrosomia (15.0 vs. 11.1%; p < 0.0001), earlier induction (GA 39.7 ± 1.3 vs. 40.1 ± 1.3 weeks; p < 0.0001) for maternal indications (39.1 vs. 21.1%; p < 0.001), and lower CDA (≤1cm; 66.4 vs. 61.4%; p < 0.005) were observed in obese versus NW. The rate of weight gain above the recommended range was higher in obese (obese 70.6% vs. NW 43.9%; p < 0.001), despite a significantly lower mean GWG compared with NW (14 ± 7.5 vs. 16.5 ± 5.6 kg; p < 0.001). Compared with NW, OW and obese demonstrated a significantly higher rCS (OW 31.1% and obese 36.9% vs. NW 24.7%; p < 0.001). BMI represented an independent factor affecting the rCS (vs. NW; OW odds ratio [OR] 1.4; confidence interval [CI] 1.2-1.7; p < 0.001; obese OR 2.3; CI 1.9-2.7 p < 0.001). CONCLUSION: In the case of IOL, obesity represents an independent factor associated with a significant increase of CS to be considered during induction counselling.

Carbetocin at elective Cesarean delivery: a sequential allocation trial to determine the minimum effective dose.

PURPOSE: The purpose of this study was to determine the intravenous dose of carbetocin required to produce effective uterine contraction in 90% of females (ED90) undergoing elective Cesarean delivery (CD) under spinal anesthesia. METHODS: We conducted a double-blind dose-finding study of carbetocin. Forty females undergoing elective CD received carbetocin intravenously upon delivery of the fetus. The dose of carbetocin for each patient was determined according to a biased-coin up-and-down sequential allocation scheme designed to cluster doses close to ED90. The initial dose was 10 µg, with increments/decrements of 5 µg. The anesthesiologist, obstetrician, and patient were blinded to the dose. The obstetrician assessed the uterine tone at one-minute intervals for five minutes after carbetocin administration. In case of unsatisfactory tone, additional uterotonics were administered. The primary outcome was requirement for additional intraoperative uterotonics. Secondary outcomes were postoperative requirement for additional uterotonics within 24 hr of delivery, estimated blood loss and side effects. RESULTS: The ED90 of carbetocin was 14.8 µg (95% confidence interval 13.7 to 15.8). Thirty-seven patients (92.5%) had adequate uterine tone with no requirement of additional intraoperative uterotonics. Two patients (5%) required postoperative uterotonics within 24 hr. The overall mean (SD) estimated blood loss was 786 (403) mL and the overall incidence of hypotension (decrease in systolic blood pressure ≥ 20% baseline) was 37.5%. CONCLUSION: Based on our study, the ED90 of carbetocin at elective CD is less than one-fifth the currently recommended dose of 100 µg. This study was registered at clinicaltrials.gov (NCT-01651130).

Postpartum uterine response to oxytocin and carbetocin.

OBJECTIVE: To obtain quantitative data on uterine contractility postpartum and compare the response of intramuscular oxytocin to carbetocin. STUDY DESIGN: A prospective study using an intrauterine pressure transducer (IUPT) to measure frequency, amplitude, and duration of contractions following the administration of either oxytocin (10 U) or carbetocin (30 microg). RESULTS: The IUPT was tolerated by all subjects and generated useful data 90% of the time in most subjects (12/16). Both drugs generated hypertonic uterine activity with contractions of similar duration. However, carbetocin resulted in contractions of sustained higher amplitude and frequency and therefore higher uterine performance as expressed by Montevideo units. This uterotonic effect of carbetocin lasted for 3 hours. CONCLUSION: IUPT monitoring generated quantitative data on postpartum uterine activity. When compared to high-dose oxytocin, a low dose of carbetocin has a more prolonged effect on uterine activity both in terms of a higher amplitude and frequency of contractions.