No. 347-Obstetric Management at Borderline Viability

Objective: The primary objective of this guideline was to develop consensus statements to guide clinical practice and recommendations for obstetric management of a pregnancy at borderline viability, currently defined as prior to 25thorn6 weeks. Intended Users: Clinicians involved in the obstetric management of women whose fetus is at the borderline of viability. Target Population: Women presenting for possible birth at borderline viability. Evidence: This document presents a summary of the literature and a general consensus on the management of pregnancies at borderline viability, including maternal transfer and consultation, administration of antenatal corticosteroids and magnesium sulfate, fetal heart rate monitoring, and considerations in mode of delivery. Medline, EMBASE, and Cochrane databases were searched using the following keywords: extreme prematurity, borderline viability, preterm, pregnancy, antenatal corticosteroids, mode of delivery. The results were then studied, and relevant articles were reviewed. The references of the reviewed studies were also searched, as were documents citing pertinent studies. The evidence was then presented at a consensus meeting, and statements were developed. Validation Methods: The content and recommendations were developed by the consensus group from the fields of Maternal-Fetal Medicine, Neonatology, Perinatal Nursing, Patient Advocacy, and Ethics. The quality of evidence was rated using criteria described in the Grading of Recommendations Assessment, Development and Evaluation methodology framework (reference 1). The Board of the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. Methods: The quality of evidence was rated using the criteria described in the Grading of Recommendations, Assessment, Development, and Evaluation methodology framework. The interpretation of strong and weak recommendations is described later. The Summary of Findings is available upon request. Benefits, Harms, and Costs: A multidisciplinary approach should be used in counselling women and families at borderline viability. The impact of obstetric interventions in the improvement of neonatal outcomes is suggested in the literature, and if active resuscitation is intended, then active obstetric interventions should be considered. Guideline Update: Evidence will be reviewed 5 years after publication to decide whether all or part of the guideline should be updated. However, if important new evidence is published prior to the 5-year cycle, the review process may be accelerated for a more rapid update of some recommendations. Sponsors: This guideline was developed with resources funded by the Society of Obstetricians and Gynaecologists of Canada and the Women and Babies Program at Sunnybrook Health Sciences Centre. Recommendations 1. Women facing decisions regarding obstetric and neonatal management at extremely preterm gestations should be counselled by an expert multidisciplinary team. Neonatal survival data vary globally, and national and local data are important elements of counselling. The data should be interpreted with the understanding that perinatal management has a role to play in these results (Weak, Moderate). 2. Whenever possible, women at periviable gestations should be offered transfer to a level 3 centre. If a clear, informed decision has been reached not to provide the infant with intensive care if delivered, and if specialized comfort care can be provided at the referring centre, the transfer may not be necessary. Decision to transfer should factor in gestational age, estimated fetal weight, and parental preferences. Practitioners should be educated about the management options for extreme prematurity and should have the option to call specialist practitioners for advice in managing these cases. Care providers should acknowledge the difficulty and disruption associated with transfer and should prepare women and their families for the process and potential outcomes (Strong, Moderate). 3. First trimester ultrasound should be offered in all pregnancies, especially when risk factors for preterm birth are present. The value of ultrasound-measured estimated fetal weight in decision-making around obstetric interventions requires study (Strong, Low). 4. In the periviable periods, antenatal corticosteroids should be administered after careful consideration of the likelihood of delivery and the resuscitation wishes of the family. If delivery is expected within 7 days, and if full resuscitation is planned, a single course of antenatal corticosteroids should be administered to women (Strong, Moderate). 5. A rescue dose of corticosteroid, when the initial course of corticosteroid was given before 25 weeks, should not currently be recommended because benefit or harm of such additional dose is not proven. Further study is required (Strong, Moderate). 6. Magnesium sulfate for neuroprotection should be given after careful consideration of the likelihood of delivery and the benefits of treatment. If delivery is expected imminently, and if full resuscitation is planned, magnesium sulfate should be administered in the extreme preterm population in accordance with local protocols and the existing SOGC guideline (Strong, Moderate). 7. Other than for maternal indications, routine Caesarean delivery in the extreme preterm population should be avoided (Strong, High). In cases of fetal malpresentation or other obstetric indications, the limitations of evidence should be discussed and a multidisciplinary approach should be used to come to a decision that considers both maternal and fetal outcome when active neonatal management is planned (Strong, Moderate). 8. Intrapartum continuous fetal monitoring should be used when active neonatal management in planned. Interpretation parameters should be used cautiously by those experienced in the care of preterm and extremely preterm gestations (Weak, Low). 9. Delayed cord clamping in the extreme preterm population is recommended. When this is not feasible, cord milking should be considered (Strong, Moderate).