Carbetocin vs. oxytocin at elective caesarean delivery: a double-blind, randomised, controlled, non-inferiority trial of low- and high-dose regimens

Carbetocin or oxytocin are given routinely as first-line uterotonic drugs following delivery of the neonate during caesarean delivery to prevent postpartum haemorrhage. Low doses may be as effective as high doses with a potential reduction in adverse effects. In this double-blind, randomised, controlled, non-inferiority trial, we assigned low-risk patients undergoing elective caesarean delivery under spinal anaesthesia to one of four groups: carbetocin 20 μg; carbetocin 100 μg; oxytocin 0.5 IU bolus + infusion; and oxytocin 5 IU bolus + infusion. The study drug was given intravenously after delivery of the neonate. Uterine tone was assessed by the obstetrician 2, 5 and 10 minutes after study drug administration according to an 11-point verbal numerical rating scale (0 = atonic, 10 = excellent tone). The primary outcome measure was uterine tone 2 min after study drug administration. The pre-specified non-inferiority margin was 1.2 points on the 11-point scale. Secondary outcomes included uterine tone after 5 and 10 minutes, use of additional uterotonics, blood loss and adverse effects. Data were available for 277 patients. Carbetocin 20 μg resulting in uterine tone of (median (IQR [range])) 8 (7-8 [1-10]) was non-inferior to carbetocin 100 μg with tone 8 (7-9 [3-10]), median (95%CI) difference 0 (-0.44-0.44). Similarly, oxytocin 0.5 IU with tone 7 (6-8 [3-10]) was non-inferior to oxytocin 5 IU with tone 8 (6-8 [2-10]), median (95%CI) difference 1 (0.11-1.89). Carbetocin 20 μg was also non-inferior to oxytocin 5 IU, and oxytocin 0.5 IU was non-inferior to carbetocin 100 μg. Uterine tone after 5 and 10 minutes, use of additional uterotonics, blood loss and adverse effects were similar in all groups.

Risk Factors Associated with Uterine Rupture and Dehiscence: A Cross-Sectional Canadian Study

OBJECTIVE

 To compare maternal and perinatal risk factors associated with complete uterine rupture and uterine dehiscence.

METHODS

 Cross-sectional study of patients with uterine rupture/dehiscence from January 1998 to December 2017 (30 years) admitted at the Labor and Delivery Unit of a tertiary teaching hospital in Canada.

RESULTS

 There were 174 (0.1%) cases of uterine disruption (29 ruptures and 145 cases of dehiscence) out of 169,356 deliveries. There were associations between dehiscence and multiparity (odds ratio [OR]: 3.2; p = 0.02), elevated maternal body mass index (BMI; OR: 3.4; p = 0.02), attempt of vaginal birth after a cesarian section (OR: 2.9; p = 0.05) and 5-minute low Apgar score (OR: 5.9; p < 0.001). Uterine rupture was associated with preterm deliveries (36.5 ± 4.9 versus 38.2 ± 2.9; p = 0.006), postpartum hemorrhage (OR: 13.9; p < 0.001), hysterectomy (OR: 23.0; p = 0.002), and stillbirth (OR: 8.2; p < 0.001). There were no associations between uterine rupture and maternal age, gestational age, onset of labor, spontaneous or artificial rupture of membranes, use of oxytocin, type of uterine incision, and birthweight.

CONCLUSION

 This large cohort demonstrated that there are different risk factors associated with either uterine rupture or dehiscence. Uterine rupture still represents a great threat to fetal-maternal health and, differently from the common belief, uterine dehiscence can also compromise perinatal outcomes.

Highly expressed ACE-2 receptors during pregnancy: A protective factor for SARS-COV-2 infection?

While previous viral pandemics showed that pregnancy was a risk factor for susceptibility and adverse outcomes, current evidence is conflicting whether SARS-CoV-2 infection during pregnancy is more severe than in the general population, with relatively low maternal and fetal/neonatal mortality rates. SARS-CoV-2 is known to enter host cells via the ACE-2 receptors, competitively occupying their binding sites. In theory, viral invasion can lead to a reduction in available ACE-2 receptors and consequently an unbalanced regulation between the ACE-AngII-AT1 axis and the ACE-2-Ang-(1-7)-MAS axis, thus enhancing pathological vasoconstriction, fibrosis, inflammation and thrombotic processes. We hypothesize that the normal pregnant state of highly expressed ACE-2 receptors leads to higher Ang-(1-7) levels and consequently more vasodilation and anti-inflammatory response to SARS-COV-2 infection. We suggest that this up-regulation of ACE-2 receptors in human gestation may actually be clinically protective and propose a potential research line to investigate this hypothesis, which may lead to future novel therapeutics.

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.

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.

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).

RECOMMENDATIONS

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.

Are increased fetal movements always reassuring?

Many studies have reported on the association of reduced fetal movements and stillbirth, but little is known about excessive fetal movements and adverse pregnancy outcome. First described in 1977, sudden excessive fetal movement was noted to reflect acute fetal distress and subsequent fetal demise. Subsequently, little was reported regarding this phenomenon until 2012. However, emerging data suggest that 10-30% of the women that subsequently suffer a stillbirth describe a single episode of excessive fetal movement prior to fetal demise. These episodes are poorly understood but may reflect fetal seizure activity secondary to fetal asphyxia, cord entanglement or an adverse intrauterine environment. At present, the challenge in managing women with excessive fetal movements is a timely assessment of the fetus to identify those women at risk of adverse fetal outcomes who may benefit from intervention.

Obesity in pregnancy: a comparison of four national guidelines

BACKGROUND

Obesity in pregnancy has become one of the most important challenges in obstetrical care given its prevalence and potential adverse impact on both mother and fetus. The primary objective of this descriptive review is to identify common themes and distinctions within the current recommendations for maternal obesity in the most updated version of four published national guidelines.

METHODS

We reviewed the following guidelines for obesity in pregnancy: American College of Obstetricians and Gynecologists (ACOG) 2015, Royal Australian and New Zealand College of Obstetricians and Gynecologists (RANZCOG) 2013, Royal College of Obstetrics and Gynecology (RCOG) 2010, and Society of Obstetrics and Gynecologists of Canada (SOGC) 2010.

RESULTS

There were no major contradictions between the guidelines, however, variations did exist. Recognition of overweight and obese populations prenatally was uniformly emphasized, so that appropriate nutrition and exercise counseling could be provided prior to pregnancy. Obesity in pregnancy was consistently defined as a body mass index of 30 kg/m² or more, and weight gain recommendations were in line with the Institute of Medicine guidelines. Counseling patients regarding the specific maternal and fetal complications in pregnancy, delivery, and postpartum which are associated with obesity was consistently emphasized. Most guidelines recommended early screening for gestational diabetes, however, specific details were not provided. All guidelines stressed the importance of available resources in clinics and the operating room specific to the obese population. Disparities were found regarding recommendations for high-dose folic acid, vitamin D supplementation, and low-dose aspirin. Thromboprophylaxis is a matter of debate, with most guidelines recommending use on an individual patient basis.

CONCLUSIONS

In general, the guidelines emphasized the importance of counseling women regarding the risks associated with obesity in pregnancy, and stressed the necessity of screening for these adverse outcomes. Initiatives to develop common terminology and reporting of outcomes in women's health are important for the development of cohesive and uniform recommendations for patient care. Disparities existed with respect to management strategies and where the further research and systematic reviews should be targeted, to allow clinicians to provide an appropriate obstetrical care pathway for obese women.

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. 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).

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.

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 (r_Spearman = 0.15, P = 0.023 and r_Spearman = 0.27, P < 0.001, respectively). Absolute NT measurements and NT percentiles (adjusted for CRL) correlated with BW ratio at delivery (r_Spearman = 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.

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.

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).

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.

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.

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).

RECOMMENDATIONS

1. Varicella immunization is recommended for all non-immune women as part of pre-pregnancy and postpartum care. (II-3B) 2. Varicella vaccination should not be administered in pregnancy. However, termination of pregnancy should not be advised because of inadvertent vaccination during pregnancy. (II-3D) 3. The antenatal varicella immunity status of all pregnant women should be documented by history of previous infection, varicella vaccination, or varicella zoster immunoglobulin G serology. (III-C) 4. All non-immune pregnant women should be informed of the risk of varicella infection to themselves and their fetuses. They should be instructed to seek medical help following any contact with a person who may have been contagious. (II-3B) 5. In the case of a possible exposure to varicella in a pregnant woman with unknown immune status, serum testing should be performed. If the serum results are negative or unavailable within 96 hours from exposure, varicella zoster immunoglobulin should be administered. (III-C) 6. Women who develop varicella infection in pregnancy need to be made aware of the potential adverse maternal and fetal sequelae, the risk of transmission to the fetus, and the options available for prenatal diagnosis. (II-3C) 7. Detailed ultrasound and appropriate follow-up is recommended for all women who develop varicella in pregnancy to screen for fetal consequences of infection. (III-B) 8. Women with significant (e.g., pneumonitis) varicella infection in pregnancy should be treated with oral antiviral agents (e.g., acyclovir 800 mg 5 times daily). In cases of progression to varicella pneumonitis, maternal admission to hospital should be seriously considered. Intravenous acyclovir can be considered for severe complications in pregnancy (oral forms have poor bioavailability). The dose is usually 10 to 15 mg/kg of BW or 500 mg/m² IV every 8 h for 5 to 10 days for varicella pneumonitis, and it should be started within 24 to 72 h of the onset of rash. (III-C) 9. Neonatal health care providers should be informed of peripartum varicella exposure in order to optimize early neonatal care with varicella zoster immunoglobulin and immunization. (III-C) Varicella zoster immunoglobulin should be administered to neonates whenever the onset of maternal disease is between 5 days before and 2 days after delivery. (III-C).

Cerebral palsy and assisted conception

Assisted reproductive technologies have been widely used over the past 30 years, and 1% to 4% of births worldwide are products of these technologies. However, adverse health outcomes related to assisted reproductive technologies, including cerebral palsy, have been reported. We extracted and reviewed all relevant studies cited by Medline from 1996 to 2010 evaluating the role of assisted reproductive technologies as a causative factor for cerebral palsy and poor long-term neurologic outcome. The research suggests that multiple pregnancy, preterm delivery, and babies small for gestational age are factors in the development of cerebral palsy. The vanishing embryo syndrome may also play a role. We review the evidence for these potentially causative factors, as well as their implications for embryo transfer policies.

Planned caesarean hysterectomy versus "conserving" caesarean section in patients with placenta accreta

OBJECTIVES

Invasive placentation (placenta accreta, increta, or percreta) presents significant challenges at Caesarean section. Caesarean hysterectomy in such circumstances may result in massive blood loss despite surgical expertise. We reviewed two divergent surgical approaches: planned Caesarean hysterectomy versus a "conserving surgery" in which the placenta is left in situ after Caesarean section.

METHODS

We conducted a single-centre retrospective review of all patients who delivered with invasive placentation between 2000 and 2009. We included only patients with antenatally diagnosed invasive placentation and planned mode of delivery.

RESULTS

Twenty-six patients met the inclusion criteria. Caesarean hysterectomy was planned in 16 patients and conserving surgery in 10. Intraoperative and postoperative complications were comparable in the two groups. Four of 10 patients initially treated by conservative surgery required a subsequent hysterectomy for severe vaginal bleeding, coagulopathy, or sepsis. No pregnancies were subsequently reported in the conserving surgery group.

CONCLUSION

An initial conserving surgical procedure is an option in patients with extensive invasive placentation, but it requires further monitoring for potential complications and carries a high subsequent hysterectomy rate.

H1N1 in pregnancy: a tertiary care centre experience

OBJECTIVE

To elucidate factors pertinent to the course and outcome of H1N1 infection in pregnancy.

METHODS

We conducted a retrospective chart review of H1N1-affected pregnant patients at Mount Sinai Hospital in Toronto, Ontario. All women who tested positive for H1N1 from June 1, 2009, to December 5, 2009, were identified. Records were reviewed to determine pregnancy status. Information from clinic and hospital charts of pregnant patients was gathered using data collection forms previously approved by the Mount Sinai Hospital Research Ethics Board.

RESULTS

Of 42 patients, 12 were inpatients and 30 were outpatients. Sixty percent of patients (25/42) presented in the third trimester, 33% (14/42) had comorbidities, and 69% were afebrile and therefore did not have a condition that met the United States Centers for Disease Control and Prevention's definition of influenza-like illness. Antiviral agents were administered promptly in most patients, but delays resulted in one third of patients being treated more than 48 hours from the onset of symptoms. Seventy-one percent (30/42) did not require hospitalization, and 58% of hospitalized patients (7/12) were admitted for reasons unrelated to H1N1. Although one quarter of hospitalized patients (3/12) had delivered at the time of discharge, no deliveries occurred because of H1N1. Most patients (91%) delivered at term. One half of the deliveries (51%) were by Caesarean section, but none of these were because of H1N1 infection. Most of the infants (88%) were appropriately grown, and none were admitted to the NICU because of H1N1.

CONCLUSION

Infection with H1N1 in pregnant women has the propensity to result in significant maternal and fetal morbidity and mortality, and requires vigilance in assessment and prompt treatment. In contrast to reports published to date, our cohort experienced a largely uncomplicated course of illness, with minimal fetal and maternal impact in most instances.