Obesity’s impact on intrapartum electronic fetal monitoring

Maternal and perinatal outcomes in nulliparous women with a booking body mass index exceeding 50 kg/m2

BACKGROUND

Women with a body mass index (BMI) >35 kg/m2 carry an increased obstetric risk; however, the experience of the Class IV and above obese nulliparous women is less understood.

AIMS

To describe maternal and perinatal outcomes in nulliparous women of booking BMI > 50 kg/m2.

MATERIALS AND METHODS

A cohort study of 48 nulliparous women who delivered between 2015 and 2019 in a tertiary hospital and had a booking BMI > 50 kg/m2. Obstetric outcome data was collated via electronic and written patient records. The relationship between mode of delivery and BMI was assessed using direct logistic regression. Multiple pregnancies and severe congenital malformations (n = 3) were excluded.

RESULTS

The mean booking BMI was 53.7 kg/m2 (SD 4.05) and mean maternal age was 30.4 years (SD = 5.7). Comorbidities included asthma (43%), essential hypertension (20%) and diabetes (61%). Antenatally, accuracy was compromised in 80% of morphology scans (n = 35). In the perinatal period, 33 women (68.8%) were induced compared to a spontaneous onset of labour in two (4.1%) women. There were nine elective caesarean sections (CS), five of which were for breech presentation. Of those who intended on vaginal delivery (n = 35), 51% (n = 18) had an emergency CS. In these women, the risk of CS increased by a factor of 1.36 for every one point increase in BMI > 50 kg/m2. The average gestational age was 37.5 weeks (SD 2.4) with 14% (n = 6) experiencing preterm deliveries. The incidence of babies born >90th percentile for gestational age was 15 (34%).

CONCLUSION

Increased BMI impairs maternal and perinatal outcomes and significantly increases the risk of emergency CS. BMI > 50 kg/m2 is associated with higher-level interventions and obstetric complications.

Performance of a Maternal Abdominal Surface Electrode System for Fetal Heart Rate and Uterine Contraction Monitoring from 34 to 37 Weeks

OBJECTIVE

The objective of this study was to compare performance of a maternal surface electrode patch with ultrasound- and tocodynamometer-based monitoring to detect fetal heart rate and uterine contractility in late preterm labors.

STUDY DESIGN

Thirty women between 340/7 and 366/7 weeks' gestation were monitored simultaneously with a Doppler/tocodynamometer system and a wireless fetal-maternal abdominal surface electrode system. Fetal and maternal heart rate and uterine contraction data from both systems were compared. Reliability was measured by the success rate and percent agreement. Deming regression and Bland-Altman analysis estimated the concordance between the systems. Uterine contractions were assessed by visual interpretation of monitor tracings.

RESULTS

The success rate for the surface electrode system was 89.5% (95% confidence interval [CI], 85.7-93.3), and for ultrasound it was 88.4% (95% CI, 84.9-91.9; p = 0.73), with a percent agreement of 88.1% (95% CI, 84.2-92.8). Results were uninfluenced by the patients' body mass. The mean Deming slope was 1 and the y-intercept was -3.0 beats per minute (bpm). Bland-Altman plots also showed a close relationship between the methods, with limits of agreement less than 10 bpm. The percent agreement for maternal heart rate was 98.2% (95% CI, 97.4-98.8), and for uterine contraction detection it was 89.5% (95% CI, 85.5-93.4).

CONCLUSION

Fetal heart rate and uterine contraction monitoring at 340/7 to 366/7 weeks using abdominal surface electrodes was not inferior to Doppler ultrasound/tocodynamometry for fetal-maternal assessment.

REGISTRATION

clinicaltrials.gov/February 20, 2017/identifier NCT03057275.

KEY POINTS

· Monitoring the preterm fetal heart rate with surface electrodes is feasible.. · Preterm contractions can be monitored with surface electrodes.. · The technique was noninferior to standard external monitors..

Does a video module improve patient adherence to recommended gestational weight gain guidelines?

OBJECTIVES

We aim to assess if implementation of an educational video module can improve patient adherence to recommended weight gain guidelines. Secondarily, we investigated if patients' knowledge about gestational weight gain was improved with use of the video, as well as if there was a difference in maternal and neonatal outcomes, and patient satisfaction.

METHODS

This was an IRB-approved, prospective cohort study conducted from February 2019 to October 2019. Patients were recruited from a large academic practice during their first trimester of pregnancy. Patients in the control cohort received routine care. Patients in the video cohort watched a 5-min educational video module about gestational weight gain. Pre-pregnancy weight and baseline demographics were recorded. All patients took a baseline questionnaire assessing gestational weight gain knowledge upon enrollment, and again 4 weeks later. Pre and post score differences were calculated. On admission to the hospital for delivery, all patients' gestational weight gain was calculated, and the overall gestational weight gain differences between the two groups were calculated. Maternal and neonatal delivery outcomes were also collected. T-tests, Mann-Whitney U tests, and Chi-square analyses were used to compare groups, and a p-value of <.05 was deemed statistically significant.

RESULTS

During the study period, 155 patients were recruited, with 79 in control cohort and 76 in video cohort, respectively. There was no significant difference in the percentage of patients who gained the appropriate amount of weight between the two groups; 25% (18/74) of patients in the control vs. 25% (17/68) of patients in video cohort (p = .926). There was no difference in the improvement of the pre and post assessment scores when compared between the two cohorts; the average score improvement was 1.72 ± 15.09% for the control, vs. 6.20 ± 12.51% for video cohort (p = .129). There was no difference in maternal or neonatal outcomes between the two groups. Patients were overall satisfied with the video module, with 67.6% (n = 45) reporting the video to be very educational.

CONCLUSIONS

Use of a video module did not improve GWG outcomes or knowledge in our study. Future work can focus on use of a recurring intervention throughout pregnancy, either with app-based technology or multiple videos.

Implementation of the combined use of non-invasive fetal electrocardiography and electrohysterography during labor: A prospective clinical study

INTRODUCTION

Fetal electrocardiography (NI-fECG) and electrohysterography (EHG) have been proven more accurate and reliable than conventional non-invasive methods (doppler ultrasound and tocodynamometry) and are less affected by maternal obesity. It is still unknown whether NI-fECG and EHG will eliminate the need for invasive methods, such as the intrauterine pressure catheter and fetal scalp electrode. We studied whether NI-fECG and EHG can be successfully used during labor.

MATERIAL AND METHODS

A prospective clinical pilot study was performed in a tertiary care teaching hospital. A total of 50 women were included with a singleton pregnancy with a gestational age between 36+0 and 42+0  weeks and had an indication for continuous intrapartum monitoring. The primary study outcome was the percentage of women with NI-fECG and EHG monitoring throughout the whole delivery. Secondary study outcomes were reason and timing of a switch to conventional monitoring methods (i.e., tocodynamometry and fetal scalp electrode or doppler ultrasound), repositioning of the abdominal electrode patch, success rates (i.e., the percentage of time with signal output), and obstetric and neonatal outcomes.

CLINICAL TRIAL REGISTRATION

Dutch trial register (NL8024).

RESULTS

In 45 women (90%), NI-fECG and EHG monitoring was used throughout the whole delivery. In the other five women (10%), there was a switch to conventional methods: in two women because of insufficient registration quality of uterine contractions and in three women because of insufficient registration quality of the fetal heart rate. In three out of five cases, the switch was after full dilation was reached. Repositioning of the abdominal electrode patch occurred in two women. The overall success rate was 94.5%. In 16% (n = 8) of women, a cesarean delivery was performed due to non-progressing dilation (n = 7) and due to suspicion of fetal distress (n = 1). Neonatal metabolic acidosis did not occur. Two neonates (4%) were admitted to the neonatal intensive care unit for complications not related to intrapartum monitoring.

CONCLUSIONS

NI-fECG and EHG can be successfully used during labor in 90% of women. Future research is needed to conclude whether implementation of electrophysiological monitoring can improve obstetric and neonatal outcomes.

Morbidly obese pregnant woman with congenital leptin deficiency: Follow-up and obstetric outcome

Congenital leptin deficiency is a rare congenital genetic disease. It is characterized by early-onset, severe morbid obesity. The disease occurs due to mutations in the LEP gene. Obesity is a severe consequence of the disease. It also causes reproductive and obstetric complications. In this study, we present a 26-year-old pregnant case who had been previously diagnosed with congenital leptin deficiency. The pregnancy made it more difficult to regulate the metabolic changes caused by the disease. Problems were held by a multidisciplinary approach, with the contribution of endocrinology and cardiology departments. The patient gave birth to a healthy girl at the 37th week of gestation. Spontaneous pregnancy resulting in a live birth is very uncommon in women with congenital leptin deficiency. The follow-up and treatment approaches during pregnancy and the obstetric outcome are presented with the literature.

Time and Effort by Labor Nurses to Achieve and Maintain a Continuous Recording of the Fetal Heart Rate via External Monitoring

OBJECTIVE

To describe the time and effort of labor and delivery (L&D) nurses working to achieve a continuous recording of the fetal heart rate via external fetal monitoring, as well as the types of aids involved in that process.

DESIGN

Descriptive study using a cross-sectional survey methodology.

PARTICIPANTS

L&D nurses practicing in New Jersey.

INTERVENTION/MEASUREMENTS

An online survey was used to collect data from labor nurses to identify if they used aids and what types of aids they used in their practice to achieve and maintain a continuous recording of the fetal heart rate via external fetal monitoring, as well as the amount of time that they spent doing so at the bedside.

RESULTS

Of the 134 nurses who participated in the survey, 50% reported spending 1 to 2 hours repositioning an individual, and 48.9% reported spending 1 to 2 hours per 12-hour shift manipulating the ultrasound transducer. Thus, up to one third of the shift was spent working to achieve a continuous recording of the fetal heart rate via external fetal monitoring. More than 99% (n = 133) of participants reported the use of aids. The most popular aids included supplemental monitoring equipment such as extra fetal monitor straps or improvised aids such as washcloths.

CONCLUSION

L&D nurses spend at least some time at the bedside manipulating the ultrasound transducer to achieve and maintain a continuous recording of the fetal heart rate via external fetal monitoring. Various aids are used to do so. Understanding the amount of time nurses spend at the bedside and the aids used for this purpose may provide a better understanding of the work of L&D nurses.

Obesity, Second Stage Duration, and Labor Outcomes in Nulliparous Women

OBJECTIVE

This study aimed to estimate second stage duration and its effects on labor outcomes in obese versus nonobese nulliparous women.

STUDY DESIGN

This was a secondary analysis of a cohort of nulliparous women who presented for labor at term and reached complete cervical dilation. Adjusted relative risks (aRR) were used to estimate the association between obesity and second stage characteristics, composite neonatal morbidity, and composite maternal morbidity. Effect modification of prolonged second stage on the association between obesity and morbidity was assessed by including an interaction term in the regression model.

RESULTS

Compared with nonobese, obese women were more likely to have a prolonged second stage (aRR: 1.48, 95% CI: 1.18-1.85 for ≥3 hours; aRR: 1.65, 95% CI: 1.18-2.30 for ≥4 hours). Obesity was associated with a higher rate of second stage cesarean (aRR: 1.78, 95% CI: 1.34-2.34) and cesarean delivery for fetal distress (aRR: 2.67, 95% CI: 1.18-3.58). Obesity was also associated with increased rates of neonatal (aRR: 1.38, 95% CI: 1.05-1.80), but not maternal morbidity (aRR: 1.06, 95% CI: 0.90-1.25). Neonatal morbidity risk was not modified by prolonged second stage.

CONCLUSION

Obesity is associated with increased risk of neonatal morbidity, which is not modified by prolonged second stage of labor.

The Noninvasive Fetal Electrocardiogram During Labor: A Review of the Literature

Importance

The introduction of the cardiotocogram (CTG) during labor has not been found to improve neonatal outcome. The search for a more reliable, less invasive, and patient-friendly technique is ongoing. The noninvasive fetal electrocardiogram (NI-fECG) has been proposed as one such alternative.

Objectives

The aim of this study was to review the literature on the performance of NI-fECG for fetal monitoring during labor. Following the PRISMA guidelines, a systematic search in MEDLINE, EMBASE, and Cochrane Library was performed. Studies involving original research investigating the performance of NI-fECG during labor were included. Animal studies and articles in languages other than English, Dutch, or German were excluded. The QUADAS-2 checklist was used for quality assessment. A descriptive analysis of the results is provided.

Results

Eight articles were included. Pooled analysis of the results of the separate studies was not possible due to heterogeneity. All studies demonstrate that it is possible to apply NI-fECG during labor. Compared with Doppler ultrasound, NI-fECG performs equal or better in most studies.

Conclusions and Relevance

NI-fECG for fetal monitoring is a promising noninvasive and patient-friendly technique that provides accurate information. Future studies should focus on signal quality throughout labor, with the aim to further optimize technical development of NI-fECG.

STAN: a reappraisal of its clinical usefulness

The automatic analysis of fetal ECG in labor has been introduced as an adjunct of traditional cardiotocography with the aim to improve the identification of fetuses with intrapartum hypoxia. Several randomized controlled trials and meta-analyses have produced conflicting results, with the most recent randomized controlled trial not demonstrating any improvement in either neonatal outcomes or reduction in operative birth rates. The objective of this review article is to present the state of art about the use of STAN technology in labor ward.

Internal fetal and uterine monitoring in obese patients and maternal obstetrical outcomes

BACKGROUND

The maternal habitus in the setting of obesity makes external monitoring of the fetal heart rate and contractions suboptimal, and internal monitors may be utilized more often in this population. Obesity is a risk factor for obstetrical infectious complications, but it is unknown whether the use of internal monitors in this population is associated with additional risks.

OBJECTIVE

This study aimed to investigate the association between the use of an intrauterine pressure catheter and a fetal scalp electrode and maternal infectious morbidity among women with obesity.

STUDY DESIGN

This secondary analysis of a prospective cohort study included women with singleton gestations admitted for labor at ≥37 weeks' gestation at a tertiary care institution from 2010 to 2014. Obesity was defined as a body mass index of ≥30 kg/m². The primary outcome was a composite maternal infectious morbidity, which included peripartum maternal fever, chorioamnionitis, and endomyometritis. Secondary outcomes were cesarean delivery and individual components of the maternal infectious composite. Multivariable logistic regression was used to compare the rates of infectious maternal morbidity, cesarean delivery, or operative vaginal delivery between patients with and without internal monitors, while adjusting for the confounders. An interaction term was included in the logistic regression models to test whether the relationship between the internal monitors and cesarean delivery or infectious morbidity was modified by the presence or absence of obesity.

RESULTS

Of the 8482 women who met the inclusion criteria for the study, 4727 (55.7%) had obesity and 3755 (44.3%) did not have obesity. The women with obesity were more likely to have internal monitors placed during labor than those without obesity (65.4% vs 50.5%; P<.001). The use of internal monitors was associated with an increased risk for the composite maternal infectious morbidity (9.9% vs 4.1%; P<.01 and adjusted odds ratio, 2.08; 95% confidence interval, 1.70-2.55). Women with obesity had a weaker association between the use of internal monitors and maternal infectious morbidity than women without obesity (P value for interaction of .02). The incidence of cesarean delivery was also significantly higher among women who had internal monitors placed during their labor course (adjusted odds ratio, 2.84; 95% confidence interval, 2.46-3.28), and this interaction was not modified by obesity.

CONCLUSION

Although a higher proportion of women with obesity have internal monitors placed during their labor course, they are not more susceptible to maternal infectious morbidity as a result of internal monitor use. Providers should not limit the necessary internal monitor use in women with obesity on the basis of concerns for maternal infectious morbidity.

Guideline No. 391-Pregnancy and Maternal Obesity Part 1: Pre-conception and Prenatal Care

OBJECTIVE

This guideline will review key aspects in the pregnancy care of women with obesity. Part I will focus on pre-conception and pregnancy care. Part II will focus on team planning for delivery and Postpartum Care.

INTENDED USERS

All health care providers (obstetricians, family doctors, midwives, nurses, anaesthesiologists) who provide pregnancy-related care to women with obesity.

TARGET POPULATION

Women with obesity who are pregnant or planning pregnancies.

EVIDENCE

Literature was retrieved through searches of Statistics Canada, Medline, and The Cochrane Library on the impact of obesity in pregnancy on antepartum and intrapartum care, maternal morbidity and mortality, obstetrical anaesthesia, and perinatal morbidity and mortality. Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to September 2018. Grey (unpublished) literature was identified through searching the websites of health technology assessment and related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the authors. Then the Maternal-Fetal Medicine Committee peer reviewed the content and submitted comments for consideration, and the Board of the Society of Obstetricians and Gynaecologists of Canada (SOGC) approved the final draft for publication. Areas of disagreement were discussed during meetings, at which time consensus was reached. The level of evidence and quality of the recommendation made were described using the Evaluation of Evidence criteria of the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in these guidelines may increase obstetrical provider recognition of the issues affected pregnant individuals with obesity, including clinical prevention strategies, communication between the health care team, the patient and family as well as equipment and human resource planning. It is hoped that regional, provincial and federal agencies will assist in the education and support of coordinated care for pregnant individuals with obesity.

GUIDELINE UPDATE

SOGC guidelines will be automatically reviewed 5 years after publication. However, authors can propose another review date if they feel that 5 years is too short/long based on their expert knowledge of the subject matter.

SPONSORS

This guideline was developed with resources funded by the SOGC.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Periviability: A Review of Key Concepts and Management for Perinatal Nursing

One of the most complex clinical problems in obstetrics and neonatology is caring for pregnant women at the threshold of viability. Births near viability boundaries are grave events that carry a high prevalence of neonatal death or an increased potential for severe lifelong complications and disabilities among those who survive. Compared with several decades ago, premature infants receiving neonatal care by today's standards have better outcomes than those born in other eras. However, preterm labor at periviability represents a more complex counseling and management challenge. Although preterm birth incidence between 20/7 and 25/7 weeks has remained unchanged, survival rates at earlier gestational ages have increased as perinatal and neonatal specialties have become more adept at caring for this at-risk population. Women face difficult choices about obstetric and neonatal interventions in light of uncertainties around survival and outcomes. This article reviews current neonatal statistics in reference to short- and long-term outcomes, key concepts in obstetric clinical management of an anticipated periviable birth, and counseling guidance to ensure shared-decision making.

Use and experiences with external fetal monitoring devices among obstetrical providers

Introduction: Fetal heart rate monitoring presents one of the few available methods for evaluating the fetus prior to birth. However, current devices on the market have significant shortcomings. We sought to describe the use and experiences with external fetal monitoring (EFM) devices among obstetrical providers.Materials and methods: We performed a cross-sectional survey in an academic medical center between April and July 2017 including nurse, midwife, and physician obstetrical providers (n = 217) who were invited to participate in this study regarding their experiences with the external fetal monitoring (EFM) device utilized by their hospital system in the outpatient, inpatient, and labor and delivery (L&D) settings. Associations between provider characteristics, device use, perception of challenging patients, and potential usefulness of an improved system were assessed by Fisher's exact test.Results: The 137 respondents (63.1%) reported difficulties monitoring obese women (98.5%), multiple gestation pregnancies (90.5%), and early gestational ages (71.5%). Over half (59.5%) of L&D nurses reported interacting with EFM devices for greater than 1-hour during a typical 12-hour shift and fewer than half (42.3%) reported being satisfied with current EFM devices. There were no statistically significant associations between provider age, experience, or time spent utilizing the devices with perception of challenging patient types.Conclusions: In conclusion, obstetrical providers perceive shortcomings of current EFM devices across all levels of provider experience and time utilizing these devices. Nurses reported significant time operating the devices, representing an opportunity to reduce time and costs with an improved device.