Committee Opinion No. 418: The Complete 11-14 Week Prenatal Sonographic Examination.

OBJECTIVE: Sonography during the first trimester provides an opportunity to assess a pregnancy in its early stage. This document provides an opinion about the implementation and content of prenatal sonographic examinations at 11-14 weeks gestation in Canada. TARGET POPULATION: Pregnant women at 11-14 weeks gestation. BENEFITS, HARMS, AND COSTS: The 11-14 week prenatal sonographic examination can provide important information that may contribute to pregnancy management. It can be used to confirm viability, establish gestational age, determine the number of fetuses, assess the adnexa/ovaries, and, in a multiple pregnancy, assess chorionicity and amnionicity. Scanning also offers an opportunity to detect fetal abnormalities and perform aneuploidy screening by measuring the nuchal translucency thickness. It may be valuable in screening for preeclampsia and other obstetrical disorders (by combining uterine artery Doppler scanning with other bio-clinical markers) and for invasive placentation. There are no physical harms to mother or fetus from offering a routine 11-14 week prenatal sonographic examination, and there are no extra costs for patients. EVIDENCE: Articles related to routine 11-14 week prenatal sonography were identified in a search of EMBASE and MEDLINE using the search terms first trimester ultrasound, nuchal translucency, and 11-14 week ultrasound. The search included all articles published on the topic until May 2019. Abstracts were reviewed by one author, and articles deemed relevant were then reviewed in full to determine whether to include them in the study. Articles that were not in English and articles that did not pertain to 11-14 week prenatal sonography were excluded. INTENDED AUDIENCE: This document is intended for sonographers, midwives, family physicians, obstetricians, and maternal-fetal medicine specialists.

Guideline No. 401: Sonographic Cervical Length in Singleton Pregnancies: Techniques and Clinical Applications.

OBJECTIVES: • To assess the association between sonography-derived cervical length measurement and preterm birth. • To describe the various techniques to measure cervical length using sonography. • To review the natural history of the short cervix. • To review the clinical uses, predictive ability, and utility of sonography-measured short cervix. OUTCOMES: Reduction in rates of prematurity and/or better identification of those at risk, as well as possible prevention of unnecessary interventions. INTENDED USERS: Clinicians involved in the obstetrical management or cervical imaging of patients at increased risk of a short cervix. TARGET POPULATION: Women at increased risk of a short cervix or at risk of preterm birth. EVIDENCE: Literature published up to June 2019 was retrieved through searches of PubMed and the Cochrane Library using appropriate controlled vocabulary and key words (preterm labour, ultrasound, cervix, cervical insufficiency, transvaginal, transperineal, cervical length, fibronectin). Results were restricted to general and systematic reviews, randomized controlled trials, controlled clinical trials, and observational studies. There were no date or language restrictions. Grey (unpublished) literature was identified through searching the websites of health technology assessment agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: The evidence and this guideline were reviewed by the Diagnostic Imaging Committee of the Society of Obstetricians and Gynaecologists of Canada, and the recommendations were made and graded according to the rankings of the Canadian Task Force on Preventive Health Care (Online Appendix Table A1). BENEFITS, HARMS, COSTS: Preterm birth is a leading cause of perinatal morbidity and mortality. Use of the sonographic technique reviewed in this guideline may help identify women at risk of preterm birth and, in some circumstances, lead to interventions that may reduce the rate of preterm birth. SUMMARY STATEMENTS (CANADIAN TASK FORCE ON PREVENTIVE HEALTH CARE GRADING IN PARENTHESES): RECOMMENDATIONS (CANADIAN TASK FORCE ON PREVENTIVE HEALTH CARE GRADING IN PARENTHESES).

Guideline No. 388-Determination of Gestational Age by Ultrasound.

OBJECTIVE: To assist clinicians in assigning gestational age based on ultrasound biometry. OUTCOMES: To determine whether ultrasound dating provides more accurate gestational age assessment than menstrual dating with or without the use of ultrasound. To provide maternity health care providers and researchers with evidence-based guidelines for the assignment of gestational age. To determine which ultrasound biometric parameters are superior when gestational age is uncertain. To determine whether ultrasound gestational age assessment is cost effective. EVIDENCE: Published literature was retrieved through searches of PubMed or MEDLINE and The Cochrane Library in 2013 using appropriate controlled vocabulary and key words (gestational age, ultrasound biometry, ultrasound dating). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies written in English. There were no date restrictions. Searches were updated on a regular basis and incorporated in the guideline to July 31, 2013. 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: Accurate assignment of gestational age may reduce post-dates labour induction and may improve obstetric care through allowing the optimal timing of necessary interventions and the avoidance of unnecessary ones. More accurate dating allows for optimal performance of prenatal screening tests for aneuploidy. A national algorithm for the assignment of gestational age may reduce practice variations across Canada for clinicians and researchers. Potential harms include the possible reassignment of dates when significant fetal pathology (such as fetal growth restriction or macrosomia) result in a discrepancy between ultrasound biometric and clinical gestational age. Such reassignment may lead to the omission of appropriate-or the performance of inappropriate-fetal interventions. SUMMARY STATEMENTS: RECOMMENDATIONS.

No 374 - Évaluation systématique de la longueur cervicale.

OBJECTIF: Passer en revue les données probantes et fournir une opinion indiquant si l'évaluation systématique de la longueur cervicale pour la prévention de l'accouchement prématuré devrait être adoptée au Canada. RéSULTATS: Les issues évaluées comprennent la prévention de l'accouchement prématuré. DONNéES PROBANTES: Nous avons interrogé les bases de données Knowledge Finder, Medline et Cochrane pour en tirer les articles publiés jusqu'en avril 2018 sur la mesure de la longueur cervicale pour la prévention de l'accouchement prématuré. CRITèRES: Les données obtenues ont été examinées et évaluées par le Comité d'imagerie diagnostique de la SOGC sous la direction des auteurs principaux, et les recommandations ont été formulées selon les lignes directrices rédigées par le Groupe d'étude canadien sur les soins de santé préventifs. AVANTAGES, DéSAVANTAGES, ET COûTS: La prévention de l'accouchement prématuré sans coûts excessifs est très importante pour la santé des mères et des familles. La présente opinion de comité résume les données probantes actuelles sur l'évaluation systématique de la longueur cervicale pour prévenir l'accouchement prématuré au Canada, détermine si elle satisfait les critères de Jungner et Wilson pour un test de dépistage et formule des recommandations pour son utilisation au Canada. VALIDATION: La présente opinion a été révisée et approuvée par le comité d'imagerie diagnostique de la SOGC et la Société des obstétriciens et gynécologues du Canada (SOGC). COMMANDITAIRE: La Société des obstétriciens et gynécologues du Canada (SOGC).

No. 374-Universal Cervical Length Screening.

OBJECTIVE: To review the evidence and provide an opinion as to whether universal cervical length screening to prevent preterm birth should be adopted across Canada. OUTCOMES: Outcomes evaluated include prevention of preterm birth. EVIDENCE: Literature searches using Knowledge Finder, Medline and Cochrane databases were searched for articles published up to April 2018 on cervical length screening for prevention of preterm birth. VALUES: The evidence obtained was reviewed and evaluated by the Diagnostic Imaging Committee of the SOGC under the leadership of the principal authors, and recommendations were made according to guidelines developed by the Canadian Task Force on Preventive Health Care. BENEFITS, HARMS, AND COSTS: The prevention of preterm birth in a cost-effective manner is of significant importance to the health of mothers and their families. This committee opinion will summarize the current evidence for universal cervical length screening to prevent preterm birth in Canada, determine whether it meets the Junger and Wilson criteria for screening tests, and make recommendations as to its use in Canada. VALIDATION: These guidelines have been reviewed and approved by the Diagnostic Imaging Committee of the SOGC and The Society of Obstetricians and Gynaecologists of Canada (SOGC). SPONSORS: The Society of Obstetricians and Gynaecologists of Canada (SOGC).

No. 257-Ultrasonographic Cervical Length Assessment in Predicting Preterm Birth in Singleton Pregnancies.

OBJECTIVES: To review (1) the use of ultrasonographic-derived cervical length measurement in predicting preterm birth and (2) interventions associated with a short cervical length. OUTCOMES: Reduction in rates of prematurity and/or better identification of those at risk, as well as possible prevention of unnecessary interventions. EVIDENCE: Published literature was retrieved through searches of PubMed and The Cochrane Library up to December 2009, using appropriate controlled vocabulary and key words (preterm labour, ultrasound, cervix, incompetent cervix, transvaginal, transperineal, cervical length, fibronectin). Results were restricted to general and systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. 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. VALUES: The evidence and this guideline were reviewed by the Diagnostic Imaging Committee and the Maternal Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada, and the recommendations were made according to the guidelines developed by The Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: Preterm birth is a leading cause of perinatal morbidity and mortality. Use of the ultrasonographic technique reviewed in this guideline may help identify women at risk of preterm birth and, in some circumstances, lead to interventions that may reduce the rate of preterm birth. SPONSORS: The Society of Obstetricians and Gynaecologists of Canada SUMMARY STATEMENTS: RECOMMENDATIONS.

Amniotic Fluid: Technical Update on Physiology and Measurement.

OBJECTIVE: OUTCOMES: EVIDENCE: A MEDLINE and KFINDER search was used to identify relevant articles, with review of bibliography identified article including Cochrane reviews and recent review articles. VALUES: The evidence collected was reviewed by the Diagnostic Imaging Committee of the Society of Obstetricians and Gynecologists of Canada. The recommendations were made according to the guidelines developed by The Canadian Task Force on Preventative Health Care (Table 1). BENEFITS, HARMS AND COSTS: Amniotic fluid assessment by ultrasound has become an integral part of fetal assessment in modern obstetrics. Abnormalities of fluid volume result in obstetrical intervention and further investigations. In Canada, there are no standard definitions of fluid volume estimation, nor a standard approach to assessing fluid. Multiple randomized trials have suggested that using a Single Pocket Estimation technique (rather than the multi pocket assessment approach known as the amniotic fluid index), will result in fewer obstetrical interventions without any increase in adverse outcomes. Recent literature suggests that there are detectable, modest changes in amniotic fluid that can occur within an hour or two of normal physiological maneuvers. This may account for the variability and inconsistent results from repeated assessments within a short period of time which can lead to confusion and generate further testing. This article hopes to describe the limitations of amniotic fluid assessment, promote a standard method of amniotic fluid assessment, and propose a common set of definitions to be used to describe amniotic fluid volume. SUMMARY STATEMENTS: RECOMMENDATION.

Mise à jour technique sur la physiologie et l'évaluation du liquide amniotique.

OBJECTIF: RéSULTATS: SOURCES DES DONNéES PROBANTES: Nous avons effectué une recherche sur MEDLINE et Kfinder pour trouver des articles pertinents, puis avons examiné les bibliographies des articles retenus, notamment des revues Cochrane et des articles de revue récents. VALEURS: Les données recueillies ont été analysées par le Comité d'imagerie diagnostique de la Société des obstétriciens et gynécologues du Canada. Les recommandations ont été classées selon les critères établis par le Groupe d'étude canadien sur les soins de santé préventifs (Tableau 1). AVANTAGES, DéSAVANTAGES ET COûTS: En obstétrique moderne, l'évaluation du volume de liquide amniotique par échographie fait partie intégrante de l'évaluation fœtale. Toute anomalie donne lieu à une intervention obstétricale et à des examens approfondis. Au Canada, il n'existe aucune définition normalisée associée à l'estimation du volume de liquide amniotique ni aucune approche d'évaluation uniforme. Plusieurs essais randomisés semblent indiquer que l'évaluation de poche unique, plutôt que de plusieurs poches (indice de liquide amniotique), diminue les interventions obstétricales sans augmenter l'incidence de résultats indésirables. La littérature récente laisse croire que des changements légers, mais détectables du liquide amniotique peuvent survenir une heure ou deux suivant des manœuvres physiologiques normales, ce qui pourrait expliquer la variabilité et le manque de cohérence des résultats d'évaluations répétées en peu de temps et ainsi créer de la confusion et donner lieu à d'autres examens. Le présent article vise à décrire les limites de l'évaluation du volume de liquide amniotique, à promouvoir une méthode d'évaluation normalisée et à proposer un ensemble commun de définitions. DéCLARATIONS SOMMAIRES: RECOMMANDATION.

RETIRED: Determination of gestational age by ultrasound.

This document has been archived because it contains outdated information. It should not be consulted for clinical use, but for historical research only. Please visit the journal website for the most recent guidelines.

Ce document a été archivé, car il contient des informations périmées. Il ne devrait pas être consulté pour un usage clinique, mais uniquement pour des recherches historiques. Veuillez consulter le site web du journal pour les directives les plus récentes.

RETIRED: The use of magnetic resonance imaging in the obstetric patient.

This document has been archived because it contains outdated information. It should not be consulted for clinical use, but for historical research only. Please visit the journal website for the most recent guidelines.

Ce document a été archivé, car il contient des informations périmées. Il ne devrait pas être consulté pour un usage clinique, mais uniquement pour des recherches historiques. Veuillez consulter le site web du journal pour les directives les plus récentes.

Archivée: Détermination de l'âge gestationnel par échographie.

Ce document a été archivé, car il contient des informations périmées. Il ne devrait pas être consulté pour un usage clinique, mais uniquement pour des recherches historiques. Veuillez consulter le site web du journal pour les directives les plus récentes.

SOGC Clinical Practice Guideline. Ultrasonographic cervical length assessment in predicting preterm birth in singleton pregnancies.

OBJECTIVES: To review (1) the use of ultrasonographic-derived cervical length measurement in predicting preterm birth and (2) interventions associated with a short cervical length. OUTCOMES: Reduction in rates of prematurity and/or better identification of those at risk, as well as possible prevention of unnecessary interventions. EVIDENCE: Published literature was retrieved through searches of PubMed and The Cochrane Library up to December 2009, using appropriate controlled vocabulary and key words (preterm labour, ultrasound, cervix, incompetent cervix, transvaginal, transperineal, cervical length, fibronectin). Results were restricted to general and systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. 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. VALUES: The evidence and this guideline were reviewed by the Diagnostic Imaging Committee and the Maternal Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada, and the recommendations were made according to the guidelines developed by The Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: Preterm birth is a leading cause of perinatal morbidity and mortality. Use of the ultrasonographic technique reviewed in this guideline may help identify women at risk of preterm birth and, in some circumstances, lead to interventions that may reduce the rate of preterm birth. SPONSORS: The Society of Obstetricians and Gynaecologists of Canada.

Initial evaluation and referral guidelines for management of pelvic/ovarian masses.

OBJECTIVES: To optimize the management of adnexal masses and to assist primary care physicians and gynaecologists determine which patients presenting with an ovarian mass with a significant risk of malignancy should be considered for gynaecologic oncology referral and management. OPTIONS: Laparoscopic evaluation, comprehensive surgical staging for early ovarian cancer, or tumour debulking for advanced stage ovarian cancer. OUTCOMES: To optimize conservative versus operative management of women with possible ovarian malignancy and to optimize the involvement of gynaecologic oncologists in planning and delivery of treatment. EVIDENCE: Published literature was retrieved through searches of PubMed or MEDLINE, CINAHL, and the Cochrane Library, using appropriate controlled vocabulary and key words. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Grey (unpublished) literature was identified by searching the web sites 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: 1. Primary care physicians and gynaecologists should always consider the possibility of an underlying ovarian cancer in patients in any age group who present with an adnexal or ovarian mass. (II-2B) 2. Appropriate workup of a perimenopausal or postmenopausal woman presenting with an adnexal mass should include evaluation of symptoms and signs suggestive of malignancy, such as persistent pelvic/abdominal pain, urinary urgency/frequency, increased abdominal size/bloating, and difficulty eating. In addition, CA125 measurement should be considered. (II-2B) 3. Transvaginal or transabdominal ultrasound examination is recommended as part of the initial workup of a complex adnexal/ovarian mass. (II-2B) 4. Ultrasound reports should be standardized to include size and unilateral/bilateral location of the adnexal mass and its possible origin, thickness of septations, presence of excrescences and internal solid components, vascular flow distribution pattern, and presence or absence of ascites. This information is essential for calculating the risk of malignancy index II score to identify pelvic mass with high malignant potential. (IIIC) 5. Patients deemed to have a high risk of an underlying malignancy should be reviewed in consultation with a gynaecologic oncologist for assessment and optimal surgical management. (II-2B).

Failure of methotrexate and internal iliac balloon catheterization to manage placenta percreta.

BACKGROUND: Placenta percreta is a rare but potentially lethal condition. Previously described conservative measures to avoid life-threatening hemorrhage and preserve fertility include use of methotrexate and uterine artery embolization. CASE: A woman with suspected placenta percreta diagnosed on ultrasound in the second trimester was delivered by classic, fundal cesarean at 30 weeks' gestation for bleeding and premature rupture of membranes. The placenta was left in situ, and she was treated with methotrexate. Postpartum bleeding 1 week later was managed by internal iliac balloon catheterization and manual transcervical removal of the placenta, which resulted in hysterectomy and required massive blood transfusion. CONCLUSION: Placenta percreta managed conservatively with methotrexate and internal iliac balloon catheterization resulted in serious morbidity.

SOGC CLINICAL PRACTICE GUIDELINE: guidelines for the management of vasa previa.

OBJECTIVES: To describe the etiology of vasa previa and the risk factors and associated condition, to identify the various clinical presentations of vasa previa, to describe the ultrasound tools used in its diagnosis, and to describe the management of vasa previa. OUTCOMES: Reduction of perinatal mortality, short-term neonatal morbidity, long-term infant morbidity, and short-term and long-term maternal morbidity and mortality. EVIDENCE: Published literature on randomized trials prospective cohort studies, and selected retrospective cohort studies was retrieved through searches of PubMed or Medline, CINAHL, and the Cochrane Library, using appropriate controlled vocabulary (e.g., selected epidemiological studies comparing delivery by Caesarean section with vaginal delivery studies comparing outcomes when vasa previa is diagnosed antenatally vs.intrapartum) and key words (e.g. vasa previa). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Searches were updated on a regular basis and incorporated into the guideline to October 1, 2008. 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 from national and international medical specialty societies. VALUES: The evidence collected was reviewed by the Diagnostic Imaging Committee and the Maternal Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and quantified using the evaluation of evidence guidelines developed by the Canadian Task Force on Preventive Health Care. BENEFITS, HARMS, AND COSTS: The benefit expected from this guideline is facilitation of optimal and uniform care for pregnancies complicated by vasa previa. SPONSORS: The Society of Obstetricians and Gynaecologists of Canada.