Fetal biophysical profile scoring: selective use of the nonstress test

Guideline No. 441: Antenatal Fetal Health Surveillance

OBJECTIVE

To summarize the current evidence and to make recommendations for antenatal fetal health surveillance (FHS) to detect perinatal risk factors and potential fetal decompensation in the antenatal period and to allow for timely intervention to prevent perinatal morbidity and/or mortality.

TARGET POPULATION

Pregnant individuals with or without maternal, fetal, or pregnancy-associated perinatal risk factors for antenatal fetal decompensation.

OPTIONS

To use basic and/or advanced antenatal testing modalities, based on risk factors for potential fetal decompensation.

OUTCOMES

Early identification of potential fetal decompensation allows for interventions that may support fetal adaptation to maintain well-being or expedite delivery.

BENEFITS, HARMS, AND COSTS

Antenatal FHS in pregnant individuals with identified perinatal risk factors may reduce the chance of adverse outcomes. Given the high false-positive rate, FHS may increase unnecessary interventions, which may result in harm, including parental anxiety, premature or operative birth, and increased use of health care resources. Optimization of surveillance protocols based on evidence-informed practice may improve perinatal outcomes and reduce harm.

EVIDENCE

Medline, PubMed, Embase, and the Cochrane Library were searched from inception to January 2022, using medical subject headings (MeSH) and key words related to pregnancy, fetal monitoring, fetal movement, stillbirth, pregnancy complications, and fetal sonography. This document represents an abstraction of the evidence rather than a methodological review.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

All health care team members who provide care for or education to obstetrical patients, including maternal fetal medicine specialists, obstetricians, family physicians, midwives, nurses, nurse practitioners, and radiologists.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Directive clinique no 441 : Surveillance prénatale du bien-être fœtal

OBJECTIF

Résumer les données probantes actuelles et formuler des recommandations pour la surveillance prénatale du bien-être fœtal afin de détecter les facteurs de risque périnatal et toute potentielle décompensation fœtale et de permettre une intervention rapide en prévention de la morbidité et la mortalité périnatales.

POPULATION CIBLE

Personnes enceintes avec ou sans facteurs maternels, fœtaux ou gravidiques associés à des risques périnataux et à la décompensation fœtale.

OPTIONS

Utiliser des examens prénataux par technologie de base et/ou avancée en fonction des facteurs de risque de décompensation fœtale. RéSULTATS: La reconnaissance précoce de toute décompensation fœtale potentielle permet d'intervenir de façon à favoriser l'adaptation fœtale pour maintenir le bien-être ou à accélérer l'accouchement. BéNéFICES, RISQUES ET COûTS: Chez les personnes enceintes ayant des facteurs de risque périnatal confirmés, la surveillance du bien-être fœtal contribue à réduire le risque d'issue défavorable. Compte tenu du taux élevé de faux positifs, la surveillance du bien-être fœtal peut augmenter le risque d'interventions inutiles, ce qui peut avoir des effets nuisibles, dont l'anxiété parentale, l'accouchement prématuré ou assisté et l'utilisation accrue des ressources de soins de santé. L'optimisation des protocoles de surveillance d'après des pratiques fondées sur des données probantes peut améliorer les issues périnatales et réduire les effets nuisibles. DONNéES PROBANTES: Des recherches ont été effectuées dans les bases de données Medline, PubMed, Embase et Cochrane Library, de leur création jusqu'à janvier 2022, à partir de termes MeSH et de mots clés liés à la grossesse, à la surveillance fœtale, aux mouvements fœtaux, à la mortinaissance, aux complications de grossesse et à l'échographie fœtale. Le présent document est un résumé des données probantes et non pas une revue méthodologique. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations Assessment, Development and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et faibles). PROFESSIONNELS CONCERNéS: Tous les membres de l'équipe de soins qui prodiguent des soins ou donnent de l'information aux patientes en obstétrique, notamment les spécialistes en médecine fœto-maternelle, les obstétriciens, les médecins de famille, les sages-femmes, les infirmières, les infirmières praticiennes et les radiologistes. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

Methods for Monitoring Risk of Hypoxic Damage in Fetal and Neonatal Brains: A Review

Fetal, perinatal, and neonatal asphyxia are vital health issues for the most vulnerable groups in human beings, including fetuses, newborns, and infants. Severe reduction in oxygen and blood supply to the fetal brain can cause hypoxic-ischemic encephalopathy, leading to long-term neurological disorders, including mental impairment and cerebral palsy. Such neurological disorders are major healthcare concerns. Therefore, there has been a continuous effort to develop clinically useful diagnostic tools for accurately and quantitatively measuring and monitoring blood and oxygen supply to the fetal and neonatal brain to avoid severe consequences of asphyxia Hypoxic-Ischemic Encephalopathy (HIE) and Neonatal Encephalopathy (NE). Major diagnostic technologies used for this purpose include fetal heart rate monitoring (FHRM), fetus scalp blood sampling (FBS), ultrasound (US) imaging, magnetic resonance imaging (MRI), x-ray computed tomography (CT), and nuclear medicine. In addition, given the limitations and shortcomings of traditional diagnostic methods, emerging technologies such as near-infrared spectroscopy (NIRS) and photoacoustic (PA) imaging have also been introduced as stand-alone or complementary solutions to address this critical gap in fetal and neonatal care. This review provides a thorough overview of the traditional and emerging technologies for monitoring fetal and neonatal brain oxygenation status and describes their clinical utility, performance, advantages, and disadvantages.

Antepartum Fetal Surveillance: ACOG Practice Bulletin, Number 229

The goal of antepartum fetal surveillance is to reduce the risk of stillbirth. Antepartum fetal surveillance techniques based on assessment of fetal heart rate (FHR) patterns have been in clinical use for almost four decades and are used along with real-time ultrasonography and umbilical artery Doppler velocimetry to evaluate fetal well-being. Antepartum fetal surveillance techniques are routinely used to assess the risk of fetal death in pregnancies complicated by preexisting maternal conditions (eg, diabetes mellitus) as well as those in which complications have developed (eg, fetal growth restriction). The purpose of this document is to provide a review of the current indications for and techniques of antepartum fetal surveillance and outline management guidelines for antepartum fetal surveillance that are consistent with the best scientific evidence.

Antenatal Testing for Women With Preexisting Medical Conditions Using Only the Ultrasonographic Portion of the Biophysical Profile

OBJECTIVE

To report the utility of the ultrasonographic biophysical profile, which includes all the components of a biophysical profile minus the nonstress test, in women with maternal indications for antepartum surveillance.

METHODS

We conducted a case series reviewing the records of all women at 32 weeks of gestation or greater with at least one indication for antenatal testing (per the American College of Obstetricians and Gynecologists) delivered by a single maternal-fetal medicine practice between 2006 and 2018. Indications included diabetes, hypertension, lupus, antiphospholipid syndrome, sickle cell disease, renal disease, heart disease, hyperthyroidism, isoimmunization, inherited thrombophilia, and prior intrauterine fetal demise. Weekly ultrasonographic biophysical profiles were initiated at 32 weeks of gestation. We calculated the test-positive rate, the percentage of women delivered for an abnormal ultrasonography biophysical profile, and the intrauterine fetal demise rate (false-negative rate).

RESULTS

Nine hundred eighty-five women underwent 3,981 ultrasonographic biophysical profiles (four per woman; range 1-11). Sixteen women had an abnormal ultrasonographic biophysical profile, for a test positive rate of 1.6% (95% CI 1.0-2.6%) per woman, or 0.4% (95% CI 0.3-0.7%) per ultrasonographic biophysical profile. Of the 16 women with abnormal ultrasonographic biophysical profiles, 13 were delivered with good outcomes and three women had normal follow-up testing and uncomplicated deliveries at a later date. There were three women with intrauterine fetal demise (false-negative rate of 0.3%, 95% CI 0.1-0.9%). One woman with intrauterine fetal demise had a factor V Leiden mutation, fetal ventriculomegaly, and fetal growth restriction. The second woman with intrauterine fetal demise had advanced maternal age, a factor V Leiden mutation, and fetal growth restriction. The third woman with intrauterine fetal demise had class B diabetes. All three intrauterine fetal demises were diagnosed antepartum with an interval from normal ultrasonographic biophysical profile to intrauterine fetal demise of 7, 7, and 6 days, respectively.

CONCLUSION

The use of ultrasonographic biophysical profile in a high-risk cohort is associated with a very low test-positive rate and a very low incidence of intrauterine fetal demise. In women with preexisting medical conditions that place them at higher risk for intrauterine fetal demise, ultrasonographic biophysical profile can be used for antenatal testing.

The effect of halogen light stimulation on duration of ultrasound parameters of biophysical profile: a randomized clinical trial

INTRODUCTION

The objective is to assess if fetal halogen light stimulation can reduce the time needed to obtain a normal biophysical profile (BPP).

METHODS

Patients scheduled for a BPP and who satisfied the inclusion criteria were prospectively randomized to halogen light stimulation and no stimulation groups. The study group was exposed to handheld halogen light for 10 s whenever fetal breathing, movement, or tone was absent through the first 5 min of BPP. The time required to achieve complete BPP score was recorded. In patients with complete BPP score who had delivery within 1 week after the test, perinatal morbidity was examined.

RESULTS

A total of 598 patients were randomized (light = 302, no light = 296). There was no difference between the two groups in terms of gestational age, maternal age, body mass index, and indication for BPP except for preterm labor (light: 9%, no light: 4%, p = 0.03). Among the patients who had a normal BPP score (n = 507), the mean (light: 7.1 ± 6 min, no light: 12.3 ± 8 min, p < 0.0001) and median (light: 4.3, no light: 8, p = 0.004) time needed to complete the BPP score was significantly less in the light stimulation group than the no stimulation group. Perinatal outcomes were not different between groups who had delivery during the first week after BPP.

CONCLUSION

Fetal halogen light stimulation can be utilized to reduce the time needed to complete a BPP. However, further studies should be conducted in order to determine the effect of this method on decreasing non-reassuring test results.

CLINICAL TRIAL REGISTRATION

The study was submitted to the Registry of Clinical Trials on 04/20/2017 (IRCT2017041633470N1). After IRCT registration on 06/07/2017, we recruited patients from 06/08/2017 till 10/15/2017.

Contemporary Obstetric Triage

IMPORTANCE

The role of obstetric triage in the care of pregnant women has expanded significantly. Factors driving this change include the Emergency Medical Treatment and Active Labor Act, improved methods of testing for fetal well-being, increasing litigation risk, and changes in resident duty hour guidelines. The contemporary obstetric triage facility must have processes in place to provide a medical screening examination that complies with regulatory statues while considering both the facility's maternal level of care and available resources.

OBJECTIVE

This review examines the history of the development of obstetric triage, current considerations in a contemporary obstetric triage paradigm, and future areas for consideration. An example of a contemporary obstetric triage program at an academic medical center is presented.

RESULT

A successful contemporary obstetric triage paradigm is one that addresses the questions of "sick or not sick" and "labor or no labor," for every obstetric patient that presents for care. Failure to do so risks poor patient outcome, poor patient satisfaction, adverse litigation outcome, regulatory scrutiny, and exclusion from federal payment programs.

CONCLUSIONS

Understanding the role of contemporary obstetric triage in the current health care environment is important for both providers and health care leadership.

TARGET AUDIENCE

This study is for obstetricians and gynecologists as well as family physicians.

LEARNING OBJECTIVES

After completing this activity, the learner should be better able to understand the scope of a medical screening examination within the context of contemporary obstetric triage; understand how a facility's level of maternal care influences clinical decision making in a contemporary obstetric triage setting; and understand the considerations necessary for the systematic evaluation of the 2 basic contemporary obstetric questions, "sick or not sick?" and "labor or no labor?"

Antenatal Surveillance in Twin Pregnancies Using the Biophysical Profile

Objectives-The nonstress test is currently the most widely used modality for antenatal surveillance in twin pregnancies, with a quoted false-positive rate of 11%-12%. Our objective was to report our experience with the sonographic portion of the biophysical profile in twin pregnancies as the primary screening modality.Methods-Women with twin pregnancies delivered by a single maternal-fetal medicine practice from 2005 to 2013 were included. We excluded monoamniotic twins. Twin pregnancies began weekly sonography for the biophysical profile starting at 32 to 33 weeks, or earlier if indicated. The nonstress test was performed if the sonographic biophysical profile score was less than 8 of 8. We reviewed biophysical profile scores and outcomes for all patients who delivered at 33 weeks or later to assess the false-positive rate for the biophysical profile, as well as the incidence of intrauterine fetal death (IUFD) after initiation of antenatal surveillance.Results-A total of 539 twin pregnancies were included. The incidence of IUFD per patient was 2 per 539 (0.4%; 95% confidence interval [CI], 0.1%-1.3%), and the incidence of IUFD per fetus was 2 per 1078 (0.19%; 95% CI, 0.05%-0.7%). The overall positive screen rate was 24 per 539 (4.45%; 95% CI, 3.0%-6.5%). The false-positive screen rate, defined as an abnormal biophysical profile that did not diagnose an IUFD or lead to delivery, was 10 per 539 (1.9%; 95% CI, 1.0%-3.4%).Conclusions-In twin pregnancies the use of the sonographic biophysical profile for routine antenatal surveillance has a low false-positive rate, with a very low incidence of IUFD. The sonographic biophysical profile should be considered as a primary mode for antenatal surveillance in twin pregnancies, with a reflex nonstress test for an abnormal score.

Fetal middle cerebral and umbilical artery Doppler after 40 weeks gestational age

OBJECTIVE

To determine the value of fetal Doppler indices named middle cerebral artery (MCA)-PI, umbilical artery (UA)-PI and MCA-PI/UA-PI ratio, and amniotic fluid volume assessment in pregnancies 280-294 d and their correlation with the mode of delivery and perinatal outcome.

STUDY DESIGN

Prospective observational study conducted on 100 whose gestational age (GA) from 40 to 42 weeks. MCA and UA Doppler and MCA-PI/UA-PI ratio, amniotic fluid volume (AFV) were assessed. They were divided into two groups based on the presence or absence of adverse perinatal outcome.

RESULTS

Women with adverse perinatal outcome showed lower MCA-PI (0.92 versus 1.29), MCA-PI:UA-PI ratio (1.04 versus 1.83), lower gestational age when assessed by ultrasound (37.82 versus 39.48 weeks), lower neonatal birth weight (2705 versus 3108 g), fetal biophysical profile (BPP) (4.55 versus 7.21) when compared to women with normal perinatal outcome. They also had higher cases with oligohydramnios (34 versus 5), and higher UA-PI (0.89 versus 0.72).

CONCLUSION

Women with adverse neonatal outcome had higher UA-PI and lower MCA-PI, MCA-PI:UA-PI ratio, GA (by US), AFV, BPP, estimated fetal weight, neonatal birth weight when compared to those with normal perinatal outcome. Women with adverse neonatal outcome had a higher rate of cesarean section mostly due to fetal distress and induced VD due to oligohydraminos compared to the normal outcome group.

Diagnosis and management of fetal growth restriction

Fetal growth restriction (FGR) remains a leading contributor to perinatal mortality and morbidity and metabolic syndrome in later life. Recent advances in ultrasound and Doppler have elucidated several mechanisms in the evolution of the disease. However, consistent classification and characterization regarding the severity of FGR is lacking. There is no cure, and management is reliant on a structured antenatal surveillance program with timely intervention. Hitherto, the time to deliver is an enigma. In this paper, the challenges in the diagnosis and management of FGR are discussed. The biophysical profile, Doppler, biochemical and molecular technologies that may refine management are reviewed. Finally, a model pathway for the clinical management of pregnancies complicated by FGR is presented.

The effect of intermittent maternal fasting on human fetal breathing movements

In order to determine the effect of maternal fasting on human fetal breathing movements (FBM), 63 healthy pregnant women with singleton uncomplicated pregnancies of 30 weeks' gestation or more, and who were fasting during Ramadan, were recruited. Maternal blood glucose level and fetal movements were recorded during and after fasting. Statistical comparison of samples before and after a meal was made using Wilcoxon's signed-ranks test. Maternal glucose level during fasting (5.1 +/- 0.5 mmol/l) was significantly (P = 0.01) lower than after breakfast (5.3 +/- 1.0 mmol/l). There was a significant association between maternal glucose levels and numbers of days faster (P = 0.01). The time needed to detect breathing movements was significantly longer (P = 0.005) during fasting than postprandial. The continuous variety of fetal breathing movement was significantly (P = 0.02) less during fasting compared to postprandial. It is concluded that intermittent maternal fasting is associated with a significant alteration in the frequency and pattern of human FBM.

Effect of short-term maternal fasting in the third trimester on uterine, umbilical, and fetal middle cerebral artery Doppler indices

OBJECTIVE

To assess the effect of short-term maternal fasting on uterine, umbilical, and middle cerebral artery Doppler indices, and on maternal serum glucose levels and fetal behavior.

METHODS

Maternal serum glucose levels, fetal biophysical profiles, and uterine, umbilical, and middle cerebral artery Doppler indices were assessed in 110 healthy women in the third trimester of pregnancy after fasting for 10-12 hours and 2 hours after a balanced meal.

RESULTS

Maternal serum glucose levels, nonstress test results, fetal breathing movements, and biophysical profile improved after a meal compared with after fasting for 10-12 hours. Uterine, umbilical, and middle cerebral artery Doppler indices were not significantly different after fasting and after a meal.

CONCLUSION

Short-term maternal fasting during the third trimester of pregnancy has no effect on uterine, umbilical, or fetal cerebral artery Doppler indices, and has a transient but significant effect on maternal serum glucose levels and fetal behavior.

Biophysical profile in the treatment of intrauterine growth-restricted fetuses who weigh <1000 g

OBJECTIVE

The aim of this study was to determine the biophysical profile (BPP) usefulness in the prediction of cord pH, base excess, and guidance regarding the timing of delivery in preterm intrauterine growth-restricted (IUGR) fetuses.

STUDY DESIGN

A BPP was performed daily in 48 IUGR fetuses and was considered abnormal when it was 2/10 on 1 single occasion or 4/10 on 2 consecutive occasions 2 hours apart.

RESULTS

The median gestational age and fetal weight for the total population was 27.6 weeks and 632 g, respectively. In 13 fetuses with a BPP of 6, there were 3 deaths, and 7 fetuses were acidemic. In 27 fetuses with a BPP of 8, there were 3 deaths, and 12 fetuses were acidemic.

CONCLUSION

BPP alone is not a reliable test in the treatment of preterm IUGR fetuses, because of high false-positive and -negative results. The common notion of a good BPP providing reassurance for at least 24 hours is not applicable in severely preterm IUGR fetuses who weigh <1000 g.

Choice of antenatal testing significantly effects a patient's work obligations

OBJECTIVE

We sought to compare two approaches to antenatal testing for their impact on the workforce.

STUDY DESIGN

This is a prospective observational study of women who presented for antenatal testing. All women were given a survey upon presentation. As per hospital protocol, nonstress testing (NST) was performed semiweekly and biophysical profile (BPP) was performed weekly. The choice of testing was determined by the attending physician. chi2- and Student's t-tests were performed where appropriate. A P-value of <0.05 was considered significant.

RESULT

A total of 195 women were surveyed. Among them, 94 women had an NST and 101 had a BPP. Overall, 59.2% were multiparous, 33.1% had to arrange for child care and 97.2% felt reassured by the testing. There were no differences in demographic characteristics, education, type of insurance or employment status between the groups. Women who had NSTs were more likely to lose time from work than those who had BPPs (218.4 versus 68.9 min; P<0.001). Of the women who had semiweekly NSTs, 80.6% would have preferred weekly testing. If the 94 women who received semiweekly testing had weekly testing, a total of 534.4 h would have been available for the workforce.

CONCLUSION

Twice-weekly NST results in a significant increase in time lost from the workforce compared with weekly BPP.

Management of small-for-gestational-age twins with absent/reversed end diastolic flow in the umbilical artery: outcome of a policy of daily biophysical profile (BPP)

OBJECTIVES

To evaluate a strategy of daily biophysical profile (BPP) for pregnancies with small-for-gestational-age twins and with absent or reversed end diastolic flow (AREDF) in the umbilical artery of one twin and to assess the latency interval between detection and delivery in monochorionic (MC) and dichorionic (DC) twin pregnancy.

METHODS

A search of the Fetal Medicine Database was carried out between 2000 and 2005 at a single tertiary centre to identify all cases with AREDF in the umbilical artery with one small-for-gestational-age twin. Active monitoring with daily BPP was undertaken, once the estimated fetal weights (EFW) was >or= 500 g and at a gestational age of >or= 24 weeks in both twins. Delivery was timed on the basis of an abnormal BPP, two equivocal BPP within 12 h or gestational age of >or= 32(+0) weeks.

RESULTS

Twenty-two MC and 17 DC twin pregnancies were identified. There were no fetal losses in the viable actively monitored MC (19) and DC (13) twins. There was a longer latency interval in the MC group at 21.7 days versus 14.4 days in the DC group (p = 0.13). Delivery was indicated for an abnormal BPP (57.8% MC vs 30.8% DC).

CONCLUSIONS

A strategy of daily BPP can be used to monitor preterm twin fetuses with AREDF, prolonging pregnancy with an acceptable perinatal outcome.

A primer on antenatal testing for neonatal nurses: part 2: tests of fetal well-being

A number of new antenatal testing tools are being used in obstetric practice to evaluate the clinical picture of the fetus in utero. Results of these tests may prompt transfer to a tertiary facility for delivery or further antenatal monitoring. Part 2 of this 2-part series will describe antenatal testing methods used to determine fetal well-being, as well as highlight the emerging developments in the field of fetal surveillance. The ability to interpret antenatal testing results may help the neonatal team triage to assure bed availability, and predict and provide appropriate staffing for new admissions, and is an important foundation for subsequent neonatal risks and clinical care.

Multiple assessment techniques evaluate antepartum fetal risks

As technology has advanced, the field of antepartum fetal evaluation has grown. As reviewed here, a variety of options are available for use in the complicated pregnancy, including application of fetal heart rate monitoring techniques, noninvasive assessment of amniotic fluid volume, sonographic evaluation of fetal behavior, and Doppler assessment of fetal blood flow. It remains unclear which test is the best for any particular situation. The NST is the simplest test to perform but has a higher false-positive rate than the biophysical profile or the CST. These two tests also appear to demonstrate superior sensitivity, at the expense of increased testing time and cost. The application of vibroacoustic stimulation improves the specificity of the NST, while the addition of a sonographic assessment of amniotic fluid volume increases sensitivity and creates an acceptable alternative as a primary test. The limited biophysical profile, with the NST component initially omitted, provides some savings in time and cost without apparent loss of sensitivity or specificity when compared with the full profile. Ultimately, while one particular technique of fetal assessment may never prove to be the best, certain techniques may have advantages over others in particular clinical situations. Umbilical artery Doppler velocimetry appears to be a useful adjunct to other forms of testing, especially in the pregnancy at risk for intrauterine growth restriction and pre-eclampsia. Recent data have shown the biophysical profile predicts the onset of amnionitis in the setting of preterm premature rupture of membranes (PROM). The sonographic assessment of amniotic fluid volume is particularly important in the serial evaluation of the pregnancy complicated by fetal growth restriction. As new technology leads to innovative forms of testing, it is expected that these new tests of fetal status will similarly add to, rather than replace, the existing items in our armamentarium.

The effect of maternal fasting on the fetal biophysical profile

OBJECTIVES

To determine fetal biophysical profile changes in women observing Ramadan with uncomplicated singleton pregnancy.

METHODS

In this cross-sectional observational study healthy women who were observing Ramadan at 30 weeks or more of gestation were recruited as well as a non-fasting control group matched for age, parity, and gestational age. Ultrasound examination included assessment of amniotic fluid volume, fetal bladder volume, fetal biophysical profile, and umbilical artery Doppler flow.

RESULTS

A total of 162 pregnant women were observed. Mean umbilical artery pulsatility index, vertical amniotic pool depth, and fetal bladder volume were similar in the study and control groups. However, there was a significant difference in biophysical scores between the two groups. In the fasting group, 30 of 81 fetuses (37%) had a score of 6/8 compared with 11 of 81 fetuses (13.6%) in the control group (P=0.001). All fetuses in both groups with a biophysical score of 6/8 showed no breathing movements.

CONCLUSIONS

Fetal breathing movements are reduced during maternal fasting.

Fetal biophysical profile

This article begins with an outline of the theoretic basis of the fetal biophysical profile, the method for the biophysical profile score (BPS), and the timing and frequency of testing. The article further discusses the clinical management based on test scores; modified methods of the BPS; and clinical application, predictive accuracy, and impact on outcome of BPS. The authors specifically examine the relationship between BPS and cerebral palsy. They conclude with a discussion of adult sequelae and fetal adaptation to asphyxia.

Fetal death after normal biophysical profile score: An eighteen-year experience

OBJECTIVE

It was our goal to determine the false-negative rate of the biophysical profile, characterize an 18-year variation in the false-negative rate, examine the relationship between the last normal biophysical profile score and death, and compare the false-negative rate of 2 disparate populations.

STUDY DESIGN

Biophysical profile scores of 86,955 patients at 2 medical centers were collected and recorded prospectively. All perinatal deaths occurring within 1 week of a normal score were similarly recorded. The annual false-negative rate, the cumulative false-negative rate, and the ratio of false-negative results in cases of subsequent fetal death to the perinatal mortality rate were calculated.

RESULTS

There were 65 fetal deaths among 86,955 fetuses. Over an 18-year study period at one institution, the false-negative rate varied but not significantly. The cumulative false-negative rate was 0.708 per 1000 at one medical center studied and 2.289 per 1000 at the other center. The average interval between last normal score and fetal death was 3.62 days and did not vary significantly between the medical centers.

CONCLUSIONS

False-negative results in cases of subsequent fetal death reflect events that are subsequent to the last normal test result. Fetomaternal hemorrhage was the single most identifiable fetal cause of false-negative results in cases of subsequent fetal death. The ratio of the false-negative rate in cases of subsequent fetal death to the perinatal mortality rate should be used as a more objective approach to reporting this value, because the false-negative rate likely reflects the underlying perinatal mortality.

A simplified fetal biophysical profile

OBJECTIVE

To modify the classic fetal biophysical profile (FBP) with the aim of obtaining rapid and accurate information about actual fetal condition in non-compromised fetuses with a subsequent favorable outcome and to be suitable for a number of outclinic patients.

METHODS

Four-hundred and ninety-four fetuses from singleton pregnancies in two randomized groups were monitored by the modified FBP (mFBP) and 168 of them after the external vibratory acoustic stimulation (VAS/mFBP). The mFBP was characterized by two main characteristics: non-stress test was excluded and the testing was finished at the moment when all of the three fetal biophysical activities became normal. The external VAS was applied only in cases with no evidence of fetal activity at the start of the FBP.

RESULTS

Of the examined fetuses, 326 fetuses in the control group were monitored by the mFBP and there were 316 (96.9%) favorable outcomes and 10 (3.1%) adverse perinatal outcomes. The sensitivity, specificity and positive and negative predictive values of the mFBP score in predicting adverse perinatal outcome were 60, 99, 66.7 and 98.7%, respectively. In the study group of 168 fetuses there were 165 (98.2%) favorable outcomes and three (1.8%) adverse perinatal outcomes. The sensitivity, specificity and positive and negative predictive values of the VAS/mFBP were 66.7, 100, 100 and 99.4%, respectively. The efficiency of the VAS/mFBP in predicting perinatal mortality alone was even higher. After the external VAS and the first 5 min of the modified testing approximately two-fifths (41.8%) of healthy fetuses with a subsequent good outcome exhibited normal in all of the three biophysical activities and approximately two-thirds (65.5%) of them after 10 min. In the VAS/mFBP group of healthy fetuses, during the same time periods, normal breathing movements were observed in 72% and 87% of fetuses, respectively.

CONCLUSIONS

According to our results the mFBP and particularly the VAS/mFBP antenatal protocol as a new and rational variant of the FBP could improve fetal assessment allowing in cases of non-compromised fetuses rapid and accurate information about actual fetal well-being. Because of its high accuracy and a reduced testing time the antepartal method with observation of fetal breathing movements after VAS is becoming acceptable as a screening of fetal well-being evaluation in outclinic conditions.

Necrotizing funisitis: clinical significance and association with chronic lung disease in premature infants

OBJECTIVES

Our purpose was to analyze the clinical significance of necrotizing funisitis, an unusual type of chronic inflammation of the umbilical cord, and to determine whether necrotizing funisitis is associated with chronic lung disease in premature infants.

STUDY DESIGN

A total of 52 perinatal factors were prospectively assessed in 18 pregnant women and their fetuses in cases of chorioamnionitis at delivery occurring at 22 to 30 gestational weeks; a statistical comparison between the necrotizing funisitis group (n = 5) and the group without necrotizing funisitis (n = 18) was carried out.

RESULTS

Significant correlations were found between necrotizing funisitis and the following factors: maternal serum C-reactive protein level on admission (p = 0.014), fetal distress (p = 0.044), umbilical artery blood pH value (p = 0.037) and polynuclear neutrophilic leukocyte count at birth (p = 0.014), chronic lung disease (p = 0.035), need for dexamethasone therapy for chronic lung disease (p = 0.029), duration of oxygen supplementation (p = 0.026), and length of hospital stay (p = 0.026).

CONCLUSIONS

There was a significant association between necrotizing funisitis and development of chronic lung disease, suggesting that necrotizing funisitis is an important risk factor for the development of chronic lung disease.

Doppler and B-mode ultrasonography in biophysical profile scoring

OBJECTIVE

Biophysical profile scoring (BPS) is a valuable antepartum test for establishing fetal well-being, although the time constraint in some clinics limits its extensive use. In this study we attempted to shorten the total test time without excluding any of the test components.

METHOD

The non-stress test (NST) part of the BPS was performed using simultaneous pulsed wave Doppler and B-mode ultrasonography (duplex NST). It was possible to observe all the components of the BPS during the same period (duplex BPS).

RESULTS

Fifty-four tests were performed on 40 pregnant patients. The mean test time was 14.3 min. A discrepancy was shown between the ultrasonographic observation and the women's perception of the fetal movements in 46% of the tests.

CONCLUSION

Duplex NST is considered a more reliable test than the classical cardiotocographic NST. Duplex BPS is proposed as an easy-to-perform, compact and time-saving modification to the classical BPS.

Fetal biophysical profile and vibratory acoustic stimulation in high-risk pregnancies

OBJECTIVES

To determine the influence of the non-stress test (NST) on the efficiency of the fetal biophysical profile (FBP) and to test the clinical usefulness of the FBP and its combination with vibratory acoustic stimulation (VAS) in managing high-risk pregnancies.

METHODS

One hundred twenty fetuses of preeclamptic patients were included in a prospective study. Five standard variables of the FBP were observed ultrasonically following NST. In cases of non-reactive NST, external VAS was applied and the FBP score calculated and compared with the FBP score before VAS.

RESULTS

Of 120 calculated FBPs, 102 (85%) had normal profile scores before VAS and 104 (86.7%) after VAS. No statistically significant difference was found. The sensitivity, specificity, and positive and negative predictive values of the FBP score in predicting poor perinatal outcome were 94.7%, 94.4%, 75% and 99%, respectively. VAS produced a high conversion (58.8%) of non-reactive NST to reactive fetal heart rate pattern. The false-negative rate of the FBP score was 9.8 per 1000, which did not increase after VAS.

CONCLUSIONS

The efficiency of the FBP score was not significantly improved by VAS, although a high conversion of non-reactive to reactive NST was produced. The FBP with its three 'acute biophysical variables' was found to be an accurate method of antepartum assessment even without an NST. The low incidence of perinatal complications among patients with normal FBP scores, permits the conservative management of preterm high-risk pregnancies.

Evaluation of the fetal assessment score in pregnancies at risk for intrauterine hypoxia

OBJECTIVE

Our purpose was to define the diagnostic value of a new fetal assessment score that is based on each of the components of the Apgar score.

STUDY DESIGN

A fetal assessment score was established to study the main fetal vital functions: (1) cardiovascular (heart rate, color of the skin in the Apgar score), now based on fetal heart rate patterns and Doppler assessment of fetal blood flow redistribution, (2) fetal respiratory (quality of breathing in the Apgar score), now based on Doppler assessment of uteroplacental perfusion, and (3) neuromuscular function (tone and reflexes in the Apgar score), now based on fetal tone and response to external stimuli. The fetal assessment score was used in the study of 110 postdate pregnancies and 103 small-for-gestational-age infants and was compared with the traditional biophysical profile score in the prediction of perinatal outcome.

RESULTS

There were significant associations between both the fetal assessment score and the biophysical profile score with fetal distress that necessitated operative delivery, low Apgar scores, and low umbilical cord arterial blood pH. However, receiver-operator characteristic plots demonstrated that the fetal assessment score was superior to the biophysical profile score in predicting fetal distress and low Apgar values particularly in the small-for-gestational-age infants. The best single parameters in predicting fetal distress were the amniotic fluid volume in the biophysical profile score and fetal heart rate patterns and pulsed Doppler measurements in the new score.

CONCLUSION

A fetal Apgar score in which respiration is assessed by placental perfusion rather than chest movements and in which skin color is assessed by centralization of fetal blood flow may be better than the traditional biophysical profile score in predicting fetal hypoxic compromise.

Late fetal death--has ultrasound a role to play in its prevention?

Late fetal death is the principle cause of perinatal mortality (PNM) in Ireland. Real-time ultrasound scanning has been suggested as a means for identifying the fetus at risk of abnormal pregnancy outcome. Using an ultrasound-based method of fetal assessment the author noted a significant reduction in late fetal death rates over a 4 year period (1985-1988: late fetal death rate: 3.1/1000) as compared to an historic control (1983-84: late fetal death rate: 7.05/10000). In addition, as operator experience increased the false positive test rate (i.e. unnecessary delivery) was noted to fall. It is suggested that real-time ultrasound assessment of the fetus may have some role to play in preventing late fetal death.

Fetal well-being: nonimaging assessment and the biophysical profile

All of the testing methods described above are very good at predicting continued fetal health when test results are reassuring. Each test also suffers from a very poor ability to predict compromise when results are abnormal. Thus, the primary value of antepartum fetal monitoring is in identifying those pregnancies that do not require immediate intervention and may be allowed to continue. Certainly, all pregnant women (regardless of risk status) should monitor fetal movement as part of their fetal surveillance. For patients at risk, a variety of testing schemes are available using combinations of the NST, CST and BPP. There are several reasons for using the NST as the primary testing method for those at risk. Even a small antenatal testing area can accommodate three or four FHR monitors, and a single antenatal testing nurse can perform several NSTs at a time. Because the BPP requires an ultrasound machine and a trained technician to perform, and because only one BPP can be done at a time, many obstetricians who do their own in-office fetal testing are unable to adopt BPP testing as their primary means of surveillance. Additionally, it is more economical to use the NST than the BPP for first-line testing. Assuming charges of $150 and $300 for the NST and BPP, respectively, and assuming that 20% of NSTs are nonreactive and require a BPP for second-line testing, the weekly cost of testing 100 patients is $21,000 for the NST and $37,500 for the BPP. This increase-in-testing cost must be balanced against the small improvement in perinatal mortality rates achieved with the use of the BPP. Because it must be performed in a hospital setting and takes an average of 90 minutes to complete, the CST is more expensive and time-consuming than either the NST or BPP and it is less frequently used as the primary method of fetal testing. In the past the CST was the most commonly used secondary test after a nonreactive NST, but use of the BPP in this situation has now become commonplace. Although the CST still has an important role in fetal testing, the BPP is better suited for use in this setting because of its technical ease and low incidence of abnormal results. Thus, many centers use the NST as the primary mode of testing for the fetus at risk, often with a sonographic assessment of AFV.(ABSTRACT TRUNCATED AT 400 WORDS)

Fetal assessment based on fetal biophysical profile scoring. IV. An analysis of perinatal morbidity and mortality

The relationship between the last biophysical profile score result and perinatal outcome was determined among a large referred population of high-risk pregnancies. A highly significant inverse linear correlation was observed for fetal distress, admission to neonatal intensive care unit, intrauterine growth retardation, 5-minute Apgar score less than 7, and umbilical cord pH less than 7.20 but not for the incidence of meconium or major anomaly. A highly significant inverse exponential (log 10) relationship was observed for perinatal mortality in total and by component parts and cause. These data strongly suggest the biophysical profile scoring method of fetal risk assessment is accurate and also provides insight into the extent of fetal compromise.

A modified scheme for biophysical profile scoring

A modified scheme for biophysical profile scoring based exclusively on real-time ultrasonographic examination is proposed and includes expanded scores of fetal movements and fetal breathing and only qualitative assessment of accelerated placental maturation, subjective ultrasonographic impression of oligohydramnios, and decreased fetal tone. This method was compared with the method of Vintzileos et al. in the first phase of this observational study and was found to have good correlation in different score categories. This method was then applied in the second phase of the study to 180 high-risk pregnancies to examine correlation with perinatal outcome variables. The relationship between results of the last total score and perinatal outcome variables shows good predictive values. Results of this preliminary study suggest that real-time ultrasonographic evaluation-based scoring of acute fetal events, namely, movements and breathing alone, may have an important role in perinatal management.

Fetal assessment based on fetal biophysical profile scoring: experience in 19,221 referred high-risk pregnancies. II. An analysis of false-negative fetal deaths

The incidence of false-negative fetal death, which is defined as stillbirth unrelated to major anomaly or alloimmunization occurring after a last normal fetal biophysical score, was determined in 19,221 referred high-risk pregnancies. The calculated rate of fetal death after a last normal test was 0.726/1000 (14 deaths), which remained relatively constant despite a progressive increase in tests and patients studied. We conclude that a normal fetal biophysical profile score confers a high probability of perinatal survival.