Amniotic fluid index versus single deepest vertical pocket: a meta-analysis of randomized controlled trials

Fetal Growth Restriction: A Comprehensive Review of Major Guidelines

Importance

Fetal growth restriction (FGR) is a common pregnancy complication and a significant contributor of fetal and neonatal morbidity and mortality, mainly due to the lack of effective screening, prevention, and management policies.

Objective

The aim of this study was to review and compare the most recently published influential guidelines on the management of pregnancies complicated by FGR.

Evidence Acquisition

A descriptive review of guidelines from the American College of Obstetricians and Gynecologists (ACOG), the Society for Maternal-Fetal Medicine, the International Federation of Gynecology and Obstetrics, the International Society of Ultrasound in Obstetrics and Gynecology, the Royal College of Obstetricians and Gynecologists, the Society of Obstetricians and Gynecologists of Canada (SOGC), the Perinatal Society of Australia and New Zealand, the Royal College of Physicians of Ireland, the French College of Gynecologists and Obstetricians (FCGO), and the German Society of Gynecology and Obstetrics on FGR was carried out.

Results

Several discrepancies were identified regarding the definition of FGR and small-for-gestational-age fetuses, the diagnostic criteria, and the need of testing for congenital infections. On the contrary, there is an overall agreement among the reviewed guidelines regarding the importance of early universal risk stratification for FGR to accordingly modify the surveillance protocols. Low-risk pregnancies should unanimously be evaluated by serial symphysis fundal height measurement, whereas the high-risk ones warrant increased sonographic surveillance. Following FGR diagnosis, all medical societies agree that umbilical artery Doppler assessment is required to further guide management, whereas amniotic fluid volume evaluation is also recommended by the ACOG, the SOGC, the Perinatal Society of Australia and New Zealand, the FCGO, and the German Society of Gynecology and Obstetrics. In case of early, severe FGR or FGR accompanied by structural abnormalities, the ACOG, the Society for Maternal-Fetal Medicine, the International Federation of Gynecology and Obstetrics, the Royal College of Obstetricians and Gynecologists, the SOGC, and the FCGO support the performance of prenatal diagnostic testing. Consistent protocols also exist on the optimal timing and mode of delivery, the importance of continuous fetal heart rate monitoring during labor, and the need for histopathological examination of the placenta after delivery. On the other hand, guidelines concerning the frequency of fetal growth and Doppler velocimetry evaluation lack uniformity, although most of the reviewed medical societies recommend an average interval of 2 weeks, reduced to weekly or less when umbilical artery abnormalities are detected. Moreover, there is a discrepancy on the appropriate timing for corticosteroids and magnesium sulfate administration, as well as the administration of aspirin as a preventive measure. Cessation of smoking, alcohol consumption, and illicit drug use are proposed as preventive measures to reduce the incidence of FGR.

Conclusions

Fetal growth restriction is a clinical entity associated with numerous adverse antenatal and postnatal events, but currently, it has no definitive cure apart from delivery. Thus, the development of uniform international protocols for the early recognition, the adequate surveillance, and the optimal management of growth-restricted fetuses seem of paramount importance to safely guide clinical practice, thereby improving perinatal outcomes of such pregnancies.

Amniotic Fluid Disorders: From Prenatal Management to Neonatal Outcomes

Amniotic fluid volume assessment has become standard in the surveillance of fetal well-being, especially in high-risk pregnancies. Amniotic fluid disorders are a frequent and important topic in fetal and perinatal medicine. However, although important advances have been achieved, many important and challenging questions remain unanswered to date. An abnormally low amniotic fluid volume, referred to as oligohydramnios, has been traditionally considered a possible indicator of placental insufficiency or fetal compromise and is associated with an increased rate of obstetric interventions. An excess of amniotic fluid, referred to as polyhydramnios, may be secondary to fetal or maternal conditions and has been associated with a variety of adverse pregnancy outcomes, especially when it is severe. The ultrasonographic detection of an amniotic fluid disorder should prompt a proper workup to identify the underlying etiology. Data on the association of isolated oligohydramnios or idiopathic polyhydramnios with adverse obstetric and perinatal outcomes are conflicting. While the management of secondary oligohydramnios is usually guided by the underlying condition, the management of isolated oligohydramnios is poorly defined. Similarly, the management of idiopathic and secondary polyhydramnios is not yet standardized. There is an urgent need for randomized clinical trials to provide stronger recommendations on the management of these two common conditions.

Evaluating the correlation between amniotic fluid volume and estimated fetal weight in healthy pregnant women

OBJECTIVES

The establishment of cut-offs for normal amniotic fluid volume (AFV) is valuable to predict perinatal outcomes. However, the most common methods to measure AFV are not accurate enough. It is important to understand factors that may be able to increase the accuracy of the calculation of AFV cut-off values. The objective of this study was to verify the correlation between AFV and estimated fetal weight (EFW).

METHODS

Records from almost 7,000 patients between 2012 and 2017 were accessed through hospital databases. The AFV measurements included in our analysis were obtained using the maximum vertical pocket technique.

RESULTS

AFV was positively correlated with EFW in the overall, male and female samples; however, the magnitude of the association was small (0.1

CONCLUSIONS

The incorporation of EFW together with other factors (e.g., gestational age, fetus sex) may increase the accuracy of the AFV cut-offs calculation and, ultimately, reduce morbidity.

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Key Words

• amniotic fluid
• estimated fetal weight
• maximum vertical pocket
• pregnancy complications

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MESH Headings

• Amniotic Fluid/diagnostic imaging
• Female
• Fetal Weight
• Gestational Age
• Humans
• Male
• Pregnancy
• Pregnant Women
• Prenatal Care
• Ultrasonography, Prenatal

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Affiliation(s)

Sara C S Souza OMNI Research Group, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
Katherine Kim OMNI Research Group, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
Alysha L J Dingwall-Harvey OMNI Research Group, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
Romina Fakhraei OMNI Research Group, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
Yan Liao OMNI Research Group, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
Laura M Gaudet OMNI Research Group, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada Department of Obstetrics and Gynecology, Kingston Health Sciences Center, Kingston, Canada Department of Obstetrics and Gynecology, Queen's University, Kingston, Canada

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Developing Clinical Artificial Intelligence for Obstetric Ultrasound to Improve Access in Underserved Regions: Protocol for a Computer-Assisted Low-Cost Point-of-Care UltraSound (CALOPUS) Study

BACKGROUND

The World Health Organization recommends a package of pregnancy care that includes obstetric ultrasound scans. There are significant barriers to universal access to antenatal ultrasound, particularly because of the cost and need for maintenance of ultrasound equipment and a lack of trained personnel. As low-cost, handheld ultrasound devices have become widely available, the current roadblock is the global shortage of health care providers trained in obstetric scanning.

OBJECTIVE

The aim of this study is to improve pregnancy and risk assessment for women in underserved regions. Therefore, we are undertaking the Computer-Assisted Low-Cost Point-of-Care UltraSound (CALOPUS) project, bringing together experts in machine learning and clinical obstetric ultrasound.

METHODS

In this prospective study conducted in two clinical centers (United Kingdom and India), participating pregnant women were scanned and full-length ultrasounds were performed. Each woman underwent 2 consecutive ultrasound scans. The first was a series of simple, standardized ultrasound sweeps (the CALOPUS protocol), immediately followed by a routine, full clinical ultrasound examination that served as the comparator. We describe the development of a simple-to-use clinical protocol designed for nonexpert users to assess fetal viability, detect the presence of multiple pregnancies, evaluate placental location, assess amniotic fluid volume, determine fetal presentation, and perform basic fetal biometry. The CALOPUS protocol was designed using the smallest number of steps to minimize redundant information, while maximizing diagnostic information. Here, we describe how ultrasound videos and annotations are captured for machine learning.

RESULTS

Over 5571 scans have been acquired, from which 1,541,751 label annotations have been performed. An adapted protocol, including a low pelvic brim sweep and a well-filled maternal bladder, improved visualization of the cervix from 28% to 91% and classification of placental location from 82% to 94%. Excellent levels of intra- and interannotator agreement are achievable following training and standardization.

CONCLUSIONS

The CALOPUS study is a unique study that uses obstetric ultrasound videos and annotations from pregnancies dated from 11 weeks and followed up until birth using novel ultrasound and annotation protocols. The data from this study are being used to develop and test several different machine learning algorithms to address key clinical diagnostic questions pertaining to obstetric risk management. We also highlight some of the challenges and potential solutions to interdisciplinary multinational imaging collaboration.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/37374.

Fetal monitoring from 39 weeks' gestation to identify South Asian-born women at risk of perinatal compromise: a retrospective cohort study

To investigate whether earlier “post-term” monitoring of South Asian (SA) pregnancies from 39 weeks’ gestation with amniotic fluid index (AFI) and cardiotocography (CTG) detected suspected fetal compromise. Retrospective cohort study of all SA-born women at an Australian health service with uncomplicated, singleton pregnancies following the introduction of twice-weekly AFI and CTG monitoring from 39 weeks. Monitoring results, and their association with a perinatal compromise composite (including assisted delivery for fetal compromise, stillbirth, and NICU admission) were determined. 771 SA-born women had earlier monitoring, triggering delivery in 82 (10.6%). 31 (4%) had a non-reassuring antepartum CTG (abnormal fetal heart rate or variability, or decelerations) and 21 (2.7%) had an abnormal AFI (≤ 5 cm). Women with abnormal monitoring were 53% (95% CI 1.2–1.9) more likely to experience perinatal compromise and 83% (95% CI 1.2–2.9) more likely to experience intrapartum compromise than women with normal monitoring. Monitoring from 39 weeks identified possible fetal compromise earlier than it otherwise would have been, and triggered intervention in 10% of women. Without robust evidence to guide timing of birth in SA-born women to reduce rates of stillbirth, earlier monitoring provides an alternative to routine induction of labour.

Management of isolated oligohydramnios in Korea: a questionnaire-based study of clinical practice patterns among the members of the Korean Society of Maternal Fetal Medicine

Objective

The aim of this survey was to investigate the recommendations and clinical practice patterns of the Korean Society of Maternal and Fetal Medicine (KSMFM) members, regarding management of isolated oligohydramnios (IO).

Methods

From December 2018 to February 2019, questionnaires were e-mailed to the KSMFM members at 257 institutes that are listed by the Korean Statistical Information Services (KOSIS) as suitable labor premises. Responses to the seven questions on the management of IO, from diagnosis to treatment, were evaluated.

Results

A total of 72 KSMFM members responded to this survey. Nearly all participants (90.1%) used the amniotic fluid index (AFI) as the primary method for estimating amniotic fluid volume. The majority of the participants (73.6%) believed that IO was a risk factor for adverse pregnancy outcomes, including abnormal fetal heart rate (73.6%), need for cesarean delivery (58.3%), intrauterine fetal demise (52.8%), and meconium aspiration syndrome (50%). Almost 70% of the participants believed that induction of labor might decrease perinatal morbidities, and that late-preterm to early-term period (36–38 gestational weeks) was a suitable timeframe for delivery, if the fetus was sufficiently grown and antenatal testing revealed reassuring results. Less than half of the participants (47.2%) believed that maternal oral or intravenous hydration was a useful intervention for IO management.

Conclusions

KSMFM members preferred labor induction at late-preterm to early-term, to decrease perinatal morbidity in cases of IO, although it was still uncertain whether labor induction improved the outcomes. Further prospective studies are needed regarding IO management.

Isolated oligohydramnios and long-term neurological morbidity of the offspring

This study aimed to assess the association between maternal-isolated oligohydramnios (IO) and offspring long-term neurological complications. A population-based retrospective cohort study was conducted, including all births at a single tertiary medical center in Israel between the years 1991 and 2014. Multiple pregnancies and potential pregnancy complications associated with oligohydramnios were excluded. The computerized obstetrical database was linked with the computerized dataset of all pediatric hospitalizations of the same medical center. Evaluation of cumulative neurological-associated hospitalizations rate over time was compared using a Kaplan-Meier survival curve. The Weibull survival parametric model was conducted to assess the neurological-associated hospitalization risk in the presence of IO, while accounting for potential confounders. A total of 190,259 pregnancies were included in the study, of which 4063 (2.13%) pregnancies were complicated with IO. Total neurological-related hospitalizations were significantly more common in the IO group (3.7% in the IO group and 3.0% in the comparison group, p = 0.005). Pervasive developmental disorder, movement disorders, developmental disorders, and degenerative and demyelization disorders were all specific neurological diagnoses significantly more common in the exposed group. The survival curve demonstrated a significantly higher cumulative hospitalization rate in the exposed group (log-rank p = 0.001). Using a multivariate model adjusting for gestational age, maternal age, and labor induction, an independent association between IO and long-term neurological morbidity of the offspring was observed (adjusted hazard ratio 1.203; 95% CI 1.02-1.42). In summary, a significant association was found between pregnancies complicated by IO and long-term neurological morbidity of the offspring.

Diagnostic utility of maximum vertical pocket versus amniotic fluid index in assessing amniotic fluid volume for the prediction of adverse maternal and fetal outcomes: a systematic review and meta-analysis

Objective: To compare the utility of maximum vertical pocket versus amniotic fluid index for predicting adverse perinatal outcomes.Methods: Systematic review of randomized clinical studies comparing these two ultrasound techniques and random-effects meta-analysis to quantify a range of perinatal outcomes.Result: Six studies with 4278 women were eligible. Use of the maximum vertical pocket reduced the rate of diagnosis of oligohydramnios (pooled relative risk 0.38; 95% confidence interval 0.27, 0.53). Use of the maximum vertical pocket was associated with significantly lower rates of non-reassuring fetal heart tracing, cesarean delivery for fetal distress, and induction of labor for oligohydramnios. There were no differences in the rates of cesarean delivery, presence of meconium, umbilical artery pH <7.1, 5-minute Apgar score <7, or admission to the neonatal intensive care unit.Conclusion: The use of maximum vertical pocket is associated with a lower rate of pregnancy intervention without any worsening of adverse pregnancy outcomes.

Oligohydramnios: should it be considered a risk factor for developmental dysplasia of the hip?

Breech, family history, first born and female sex are the main risk factors described for developmental dysplasia of the hip (DDH). Foot abnormalities and oligohydramnios have also been listed. Recent studies have discredited torticollis, multiple gestation pregnancy, mode of delivery and prematurity as risk factors. Definition of oligohydramnios in the literature is inconsistent. Our aim was to investigate the term oligohydramnios and evaluate whether it should be considered a risk factor for DDH. All live births in our institution between 2001 and 2014 were included. We identified all pregnancies classed as reduced amniotic fluid (AF) or oligohydramnios over that period. Data on DDH, breech presentation, female sex and positive family history were collected. The significance level was set to 5%. We identified 73 990 live births, 3408 pregnancies were classed as reduced AF or oligohydramnios. The incidence of DDH (Graf type IIb and higher) was 1: 1000 (75 babies, 18 bilateral). Oligohydramnios/reduced AF was found in 12 (16%) DDH babies. Breech presentation was found in 24 (32%), positive family history in 19 (25%) and female sex in 71 (94.7%). Oligohydramnios was found to be associated with a higher odds ratio (OR) for DDH [OR = 3.9, 95% confidence interval (CI): 2.1-7.3] as were breech presentation (OR = 10.6, 95% CI: 6.5-17.1) and female sex (OR = 19.1, 95% CI: 7-52.4). All examined risk factors showed statistical significance (P < 0.05). A regression analysis was performed to control for interactions and confounding factors and confirmed the findings. On the basis of our findings the diagnosis of reduced AF/oligohydramnios in consecutive antenatal sonographic scans should be regarded as an independent risk factor for DDH and be considered in any future studies regarding DDH. Level of evidence: Level IV: Case series.

How Well Do the Popular Ultrasonic Techniques Estimate Amniotic Fluid Volume and Diagnose Oligohydramnios, in Fact?

The aims of the study were to compare the different estimation methods for the diagnosis of oligohydramnios and to determine concordance between estimated amniotic fluid volume (AFV) measured by ultrasonography and actual AFV measured directly. Another purpose was to investigate the effect of oligohydramnios on neonatal outcome. This study was done at a tertiary care center. The participants were scheduled between 37 and 40 weeks for cesarean delivery. Estimated AFV was ultrasonographically assessed, and then actual AFV was directly measured during the cesarean delivery to compare the subjective method (SM), amniotic fluid index (AFI), single deepest pocket (SDP), and 2-diameter pocket. Totally, 138 patients were included in the present study. Of 35 (34%), 24 (21%), 12 (9.5%), and 10 (7.8%) were defined as oligohydramnios by the SM, AFI, SDP, and 2-diameter pocket, respectively. The number of patients with actual oligohydramnios was 35 (34%). Most authors suggest as a method use of the SDP more than the AFI, because of overmanagement through the AFI. However, this study, which was conducted using both nonprejudiced and criterion-standard methods, showed that the SM and AFI technique were more successful to estimate oligohydramnios than other methods. Also, adverse pregnancy outcome was not closely associated with isolated oligohydramnios.

Novel Computerized Analytic Technique for Quantification of Amniotic Fluid Volume in Fetal MRI

OBJECTIVE. Fetal MRI is increasingly used in the evaluation of suspected congenital anomalies. Assessment of amniotic fluid volume (AFV) is crucial, but no automated quantitative technique is currently available for MRI. The purpose of this study was to develop and evaluate an analytic technique for quantifying AFV in fetal MRI. MATERIALS AND METHODS. Two MRI phantoms containing known quantities of synthetic amniotic fluid were created. A 3D steady-state free precession sequence was used for 1.5-T MRI of the phantoms and as part of a standard clinical fetal MRI protocol. Software was developed and used to retrospectively calculate AFV for the phantom and 20 clinical MRI examinations. Times to completion were recorded. AFV was also calculated by a manual hand-tracing method. To evaluate performance, paired t tests were used to compare computer-generated measurements with known phantom volumes. Intraclass correlation coefficients were calculated to assess agreement between computer-generated and manual measurements. RESULTS. There was no significant difference between computer-generated measurements of known AFV in the MRI phantoms (p > 0.11). When the software program was applied to the clinical MRI examinations, the mean time to complete AFV measurement was 110 seconds. There was excellent reliability between total AFV calculated by the two software users and by means of manual measurements (intraclass correlation coefficient, 0.995; p < 0.01). CONCLUSION. The computerized analysis evaluated in this study rapidly and accurately quantifies AFV in fetal MRI. The results are concordant with known phantom volumes and manual measurements. The technique is promising for objective MRI evaluation of AFV and has the potential to improve prenatal diagnosis and management.

Managing fetal growth restriction: surveillance tests and their interpretation

The main challenges in pregnancies affected by fetal growth restriction consist in identifying signs of disease progression and determining the appropriate timing of delivery. The risk of continuing the pregnancy must be balanced with the risk of prematurity, which depends on gestational age. To allow appropriate monitoring of the growth-restricted fetus, several surveillance tests are available. These include ultrasound Doppler velocimetry of feto-placental vessels, cardiotocography, and amniotic fluid evaluation. It is well known that the combination of tests performs better than each test alone to predict fetal deterioration. The interpretation of test results depends on the gestational age and on the nature of the growth disorder (early- vs. late-onset disease). Appropriate knowledge on the surveillance tests interpretation and the frequency at which they need to be performed is crucial in managing fetal growth restriction, in order to produce better outcome and prevent stillbirth, and at the same time to avoid unnecessary interventions.

Sonographic Estimation of Amniotic Fluid Volume Using the Amniotic Fluid Index and the Single Deepest Pocket in a Resource-Limited Setting

Objective

To determine the normal value of amniotic fluid (AF) volume among pregnant women in a Northern Nigerian population and to determine if there is a relationship between AF index (AFI) and single deepest pocket (SDP) with anthropometric variables.

Materials and Methods

A prospective cross-sectional study was conducted among singleton pregnant women at late second and third trimester attending the antenatal clinic in Abubakar Tafawa Balewa Teaching Hospital, Bauchi, from December 2016 to April 2017. The mean AFI and SDP were measured by sonography. Ethical approval was obtained from the institution and informed consent was sought for from all the participants. Descriptive statistics, i.e. mean, standard deviation, and correlation coefficient, were used for the analysis.

Results

A total of 206 women, aged between 18 and 40 years, with fetal gestational ages between 22 and 39 weeks were included in the study. The values for AFI in the study ranged from 12 to 28.7 cm, with a mean value of 19.84 ± 3.64 cm, and SDP ranged from 3.7 to 9.1 cm with a mean value of 6.04 ± 1.12 cm. This study found a weak relationship between the anthropometric variables and AFI and SDP and a strong relationship between AFI and SDP with a correlation coefficient of R = 0.901 and P = 0.014.

Conclusion

This study found the mean values for AF volume using AFI and SDP in the studied population to be 19.84 ± 3.64 cm and 6.04 ± 1.12 cm, respectively; a strong positive relationship between AFI and SDP; and a negative relationship between body mass index with AFI and SDP.

Updating the amniotic fluid index nomograms according to perinatal outcome

Background: The two most commonly used nomograms for amniotic fluid index (AFI) were developed by Moore and Cayle and Magann et al. However, there are several inconsistencies between the two methods.Objective: The aim of the study was to determine whether these differences carry clinical significance.Methods: A retrospective cohort of women with singleton pregnancies evaluated for AFI during pregnancy at a tertiary medical center in 2007-2014 were divided into five groups: group A, definite oligohydramnios-AFI below the fifth percentile according to the nomograms of both Moore and Cayle and Magann et al.; group B, intermediate oligohydramnios-AFI below the fifth percentile according to only one nomogram (Moore and Cayle); group C, euhydramnios-normal AFI according to both nomograms; group D, intermediate polyhydramnios-AFI above the 95th percentile according to one nomogram (Magann et al.); group E, definite polyhydramnios-above the 95th percentile according to both nomograms. The association of group by maternal and perinatal outcomes was analyzed.Results: A total of 6987 women were included: group A, 996 (14%); group B, 1344 (19%); group C, 2561 (37%); group D, 1051 (15%); group E, 1034 (15%). Group B (intermediate oligohydramnios) was characterized by significantly lower rates of adverse perinatal outcomes than group A (definite oligohydramnios): small for gestational age neonate (12.3 versus 15.2%, p = .05), neonatal intensive care unit admission (11.1 versus 21.5%; p < .001), composite respiratory outcome (4.8 versus 9.8%; p < .001), and neonatal sepsis (6.4 versus 10.8%; p < .001). No such differences were found between groups B and C. Group D (intermediate polyhydramnios) differed from group E (definite polyhydramnios) by lower rates of 5 minutes Apgar score <7 (1.3 versus 3.2%; p = .003), neonatal intensive care unit admission (10.9 versus 14.4%; p = .02), and major congenital anomalies (1.7 versus 5.6%; p = .02). There was no difference in these parameters between groups D and C.Conclusion: This study suggests that intermediate oligohydramnios and intermediate polyhydramnios are not associated with adverse perinatal outcomes. Outcome in these pregnancies is similar to pregnancies with euhydramnios. Commonly used AFI nomograms should be updated.

Is pregnancy associated plasma protein-A (PAPP-A) a marker for adverse perinatal outcomes in preterm isolated oligohydramnios cases?

OBJECTIVE

Isolated oligohydramnios is defined as an amniotic fluid index below five centimeter with no other coexisting condition. There are still controversies about the management and pregnancy outcomes. A marker predicting these is crucial. Low pregnancy associated plasma protein-A levels were reported to be related with adverse pregnancy outcomes. We aimed to determine the role of first trimester pregnancy associated plasma protein-A for poor outcomes in preterm isolated oligohydramnios cases.

MATERIAL AND METHODS

Fifty-one patients with singleton pregnancies diagnosed as isolated oligohydramnios at 28/0-36/6 weeks of gestation and 110 gestational age matched healthy controls between January and December 2015 were included. Maternal age, gestational age at delivery, mode of delivery, indication for cesarean section, Apgar scores at first and fifth minutes, birth weight, neonatal intensive care unit admission and mortality were recorded. Pregnancy associated plasma protein-A levels were compared between groups and its role in adverse perinatal outcomes was evaluated.

RESULTS

Pregnancy associated plasma protein-A levels and pregnancy outcomes were similar in two groups (p > 0.050) except birth weight, gestational age at delivery and presence of fetal distress. Pregnancy associated plasma protein-A levels did not differ in terms of delivery mode, presence of fetal distress, first and fifth minutes Apgar scores and neonatal intensive care unit admission (p = 0.323,0.650,0.990,0.112,0.853). Also, it was not determined as a risk factor for cesarean section, presence of fetal distress, low Apgar scores and neonatal intensive care unit admission.

CONCLUSION

Pregnancy associated plasma protein-A, a well-known prognostic factor for some of high risk pregnancy conditions, may not be used as a marker in preterm isolated oligohydramnios cases.

Intrauterine Growth Restriction. Guideline of the German Society of Gynecology and Obstetrics (S2k-Level, AWMF Registry No. 015/080, October 2016)

AIMS

The aim of this official guideline published and coordinated by the German Society of Gynecology and Obstetrics (DGGG) was to provide consensus-based recommendations obtained by evaluating the relevant literature for the diagnostic treatment and management of women with fetal growth restriction.

METHODS

This S2k guideline represents the structured consensus of a representative panel of experts with a range of different professional backgrounds commissioned by the Guideline Committee of the DGGG.

RECOMMENDATIONS

Recommendations for diagnostic treatment, management, counselling, prophylaxis and screening are presented.

Isolated Oligohydramnios at Term as an Indication for Labor Induction: A Systematic Review and Meta-Analysis

OBJECTIVE

To investigate whether isolated oligohydramnios at term is associated with increased rates of perinatal morbidity and mortality and whether induction of labor in term pregnancies with isolated oligohydramnios is superior to conservative management in reducing perinatal morbidity and mortality.

STUDY DESIGN

We searched databases from inception to May 2015. We included studies that evaluated isolated oligohydramnios at term and perinatal outcome. Each outcome was analyzed separately, performing a comparative analysis between the study and control groups.

RESULTS

Twelve studies were included with 35,999 women: 2,414 (6.7%) with isolated oligohydramnios and 33,585 (93.29%) with normal amniotic fluid index. Patients with isolated oligohydramnios had significantly higher rates of labor induction [odds ratio (OR) 7.56, confidence interval (CI) 4.58-12.48] and Cesarean sections (OR 2.07, CI 1.77-2.41). There were higher rates of an Apgar score <7 at 1 and 5 min (OR 1.53, CI 1.03-2.26, and OR 2.01, CI 1.3-3.09, respectively) and admission to the neonatal intensive care unit (OR 1.47, CI 1.17-1.84). There were no significant differences in cord pH <7.1 and meconium-stained amniotic fluid. In the single randomized trial comparing induction of labor with expectant management, no differences were found in any significant maternal or neonatal outcomes.

CONCLUSION

Isolated oligohydramnios at term is associated with significantly higher rates of labor induction, Cesarean sections, and short-term neonatal morbidity.

A comparison between amniotic fluid index and the single deepest vertical pocket technique in predicting adverse outcome in prolonged pregnancy

OBJECTIVE

to compare perinatal outcome in induced postterm pregnancies with normal amniotic volume and in patients with prolonged pregnancy undergone induction for oligohydramnios, evaluated by two different ultrasonographic methods.

METHODS

amniotic fluid volume was measured, using Single Deepest Vertical Pocket (SDVP) and Amniotic Fluid Index (AFI), in 961 singleton uncomplicated prolonged pregnancies. In 109 of these patients, hospitalization was planned for induction of labor, during or after 42 weeks of gestation, for oligohydramnios, postterm pregnancy and other indications in 47, 51 and 11 cases, respectively. Perinatal outcome included: rate of caesarean section, fetal distress, non reassuring fetal heart tracing, presence of meconium, umbilical artery pH < 7.1, Apgar score at 5 minutes < 7, admission to neonatal intensive care unit (NICU).

RESULTS

oligohydramnios was diagnosed in 4.89% of cases, when at least one of the two methods was used. A reduced AFI and SDVP value identified 4.47% and 3.75% of cases, respectively, even if without statistical difference. No statistical differences were reported in perinatal outcomes in postterm versus prolonged pregnancies with oligohydramnios, also in relation to the two different ultrasonographic methods.

CONCLUSIONS

oligohydramnios is more frequently diagnosed using AFI than SDVP, consequently determining a higher rate of induction of labor. Moreover, perinatal outcome in prolonged induced pregnancies is not affected by oligohydramnios.

An Update on Maternal Hydration Strategies for Amniotic Fluid Improvement in Isolated Oligohydramnios and Normohydramnios: Evidence from a Systematic Review of Literature and Meta-Analysis

OBJECTIVE

Several trials aimed at evaluating the efficacy of maternal hydration (MH) in increasing amniotic-fluid-volume (AFV) in pregnancies with isolated oligohydramnios or normohydramnos have been conducted. Unfortunately, no evidences support this intervention in routine-clinical-practice. The aim of this systematic-literature-review and meta-analysis was to collect all data regarding proposed strategies and their efficacy in relation to each clinical condition for which MH-therapy was performed with the aim of increasing amniotic-fluid (AF) and improving perinatal outcomes.

MATERIALS AND METHODS

A systematic literature search was conducted in electronic-database MEDLINE, EMBASE, ScienceDirect and the Cochrane-Library in the time interval between 1991 and 2014. Following the identification of eligible trials, we estimated the methodological quality of each study (using QADAS-2) and clustered patients according to the following outcome measures: route of administration (oral versus intravenous versus combined), total daily dose of fluids administered (<2000 versus >2000), duration of hydration therapy: (1 day, >1 day but <1 week, >1 week), type of fluid administered (isotonic versus hypotonic versus combination).

RESULTS

In isolated-oligohydramnios (IO), maternal oral hydration is more effective than intravenous hydration and hypotonic solutions superior to isotonic solutions. The improvement in AFV appears to be time-dependent rather than daily-dose dependent. Regarding normohydramnios pregnancies, all strategies seem equivalent though the administration of hypotonic-fluid appears to have a slightly greater effect than isotonic-fluid. Regarding perinatal outcomes, data is fragmentary and heterogeneous and does not allow us to define the real clinical utility of MH.

CONCLUSIONS

Available data suggests that MH may be a safe, well-tolerated and useful strategy to improve AFV especially in cases of IO. In view of the numerous obstetric situations in which a reduced AFV may pose a threat, particularly to the fetus, the possibility of increasing AFV with a simple and inexpensive practice like MH-therapy may have potential clinical applications. Considering the various strategies of maternal hydration implemented in the treatment of IO, better results were observed when treatment was based on a combination of intravenous (for a period of 1 day) and oral (for a period of at least 14 days) hypotonic fluids (≥2000ml).

Timing of induction of labor

Determining the optimal timing for induction of labor is critical in minimizing the risks to maternal and fetal health. While data are available to guide us in some clinical situations, such as hypertension and diabetes, many gaps in knowledge still exist in others, including cholestasis of pregnancy, fetal anomalies, and placental abruption. This review of the currently available literature assesses the risks and benefits of preterm and early term induction in a wide variety of maternal and fetal conditions.

Effects of Passive Hydrotherapy WATSU (WaterShiatsu) in the Third Trimester of Pregnancy: Results of a Controlled Pilot Study

Background. WATSU (WaterShiatsu) is a complementary therapeutic treatment method comprising passive stretches and massage techniques administered in 35°C warm water. Pregnant women claim safe methods to reduce pain, stress, and fatigue. Therefore, we conducted a pilot study evaluating the effects of WATSU on pregnancy-related complaints in third trimester pregnant women. Methods. Nine healthy pregnant women at gestational week ≥34 were included in an intervention group (receiving WATSU) and compared to eight women in a passive control group (receiving no treatment). WATSU was performed on days 1 and 4 of the study, accompanied by ultrasound examinations. Outcomes include physiological and psychometric as well as qualitative data. Participants in the control group completed questionnaires only. Results. WATSU was found to significantly lower participants' levels of stress and pain and to improve their mental health-related quality of life and mood. In comparison to the passive control group, participants in the intervention group reported reduction in perceived stress from day 1 to day 8 (P = 0.036, Cohen's f = 0.57). Qualitative data indicate that WATSU was appreciated as enjoyable and deeply relaxing. No negative side effects were reported. Conclusion. Our findings support the notion that WATSU yields therapeutic benefits for pregnant women and warrant further research. This study has been registered at ClinicalTrials.gov: NCT01708018.

Borderline amniotic fluid index and perinatal outcomes in the uncomplicated term pregnancy

OBJECTIVE

To determine perinatal outcomes in uncomplicated term pregnancies with a borderline amniotic fluid index (AFI).

METHODS

A retrospective review was conducted of uncomplicated singleton pregnancies at term (>37 weeks). Borderline and normal AFI were defined as 5.1 ≤ AFI ≤ 8.0 cm and 8.1 ≤ AFI ≤ 24 cm, respectively. Adverse perinatal outcomes, cesarean delivery for non-reassuring fetal heart rate testing, meconium-stained amniotic fluid, a 5-min Apgar score of <7, admission to the neonatal intensive care unit (NICU), and whether the neonate was small for gestational age were compared between the borderline and normal AFI groups.

RESULTS

Borderline AFI was not significantly associated with cesarean delivery for non-reassuring fetal heart rate testing (p = 0.513), meconium-stained amniotic fluid (p = 0.641), admission to the NICU (p = 0.368), or a 5-min Apgar score of <7 (p = 1.00). However, the number of neonates who were small for gestational age (p = 0.021) and rates of induction of labor (p < 0.001) were significantly higher in the borderline group. Multiple logistic regression analysis showed that borderline AFI was not associated with cesarean delivery for non-reassuring fetal heart rate testing (odds ratio [OR] = 0.72, 95% confidence interval [CI] 0.27-1.91, p = 0.52).

CONCLUSION

In uncomplicated term pregnancies, a borderline AFI does not increase the risk of adverse perinatal outcomes.

[Accuracy of ultrasound estimated fetal weight performed by residents at delivery day]

Ultrasound fetal weight estimation (EFW) has become a routine practice in obstetrics with a major impact on obstetrical management.

OBJECTIVES

To evaluate the accuracy of sonographic fetal weight estimations performed by residents in obstetrics at the delivery day and to search parameters influencing this exam.

METHODS

A prospective study performed in 299 patients at 37 weeks of gestation or more, during their delivery day. Ultrasound fetal weight estimations were performed by residents and compared to birth weights (BW). The estimated fetal weight (EFW) was calculated using the formula of Hadlock: Log10 EPF=1,335+0.0316 BIP+0,0457 PA+0,1623 LF-0,0034 PA LF.

RESULTS

Mean absolute difference between EFW and BW was 200g [100-450]. Mean absolute percentage error was 5.71 % [2.7-11.37]. The proportion of the EFW within 10 % of BW was 69.6 %. There was a good correlation between EFW and BW (R=0.79). Obesity and fetal macrosomia had negatively influenced ultrasound performance. For the diagnosis of macrosomia, ultrasound has a sensibility of 38 % and a specificity of 99.59 %.

CONCLUSION

Ultrasound fetal weight estimations performed by residents in the delivery room were as accurate as those performed by experimented sonographers. Thus, the predictive performance remains limited with a low sensitivity in the diagnosis of macrosomia.

Association and prediction of amniotic fluid measurements for adverse pregnancy outcome: systematic review and meta-analysis

BACKGROUND

Measurements of amniotic fluid volume are used for pregnancy surveillance despite a lack of evidence for their predictive ability.

OBJECTIVE

To evaluate the association and predictive value of ultrasound measurements of amniotic fluid volume for adverse pregnancy outcome.

SEARCH STRATEGY

Electronic databases (inception to October 2011), reference lists, hand searching of journals, contact with experts.

SELECTION CRITERIA

Studies comparing measurements of amniotic fluid volume with adverse outcome, excluding pre-labour ruptured membranes or congenital/structural anomalies.

DATA COLLECTION

Data on study characteristics, design, quality. Random effects meta-analysis to estimate summary odds ratios (prognostic association) and summary sensitivity, specificity and likelihood ratios (predictive ability).

MAIN RESULTS

Forty-three studies (244,493 fetuses) were included demonstrating a strong association between oligohydramnios (varying definitions) and birthweight <10th centile (summary odds ratio [OR] 6.31, 95% confidence interval [95% CI] 4.15-9.58; high-risk population [author definition] n = 6 studies, 28,510 fetuses), and mortality (neonatal death any population summary OR 8.72, 95% CI 2.43-31.26; n = 6 studies, 55,735 fetuses; and perinatal mortality high-risk population summary OR 11.54, 95% CI 4.05-32.9; n = 2 studies, 27;891 fetuses). There was a strong association between polyhydramnios (maximum pool depth >8 cm or amniotic fluid index ≥25 cm) and birthweight >90th centile (OR 11.41, 95% CI 7.09-18.36; n = 1 study, 3960 fetuses). Despite strong associations, predictive accuracy for perinatal outcome was poor.

AUTHOR'S CONCLUSION

Current evidence suggests that oligohydramnios is strongly associated with being small for gestational age and mortality, and polyhydramnios with birthweight >90th centile. Despite strong associations with poor outcome, they do not accurately predict outcome risk for individuals.

Amniotic fluid as a vital sign for fetal wellbeing

Introduction: Amniotic fluid, once thought to merely provide protection and room for necessary movement and growth for the fetus, is now understood to be a highly complex and dynamic system that is studied as a data point to interpret fetal wellbeing. Methods: Assessment of amniotic fluid volume is now routine when performing a sonographic evaluation of fetal status and is an important consideration in the assessment and management of perinatal morbidity and mortality.1,2 In this review, we will cover the dynamics that affect amniotic fluid volume, review methods for measurement and quantification of volume, review definitions for normative data as related to neonatal outcomes, and provide evidence based guidance on the workup and management options for oligoydramnios and polyhydramnios in singleton and twin pregnancies. Conclusions: When abnormalities of fluid exist, appropriate workup to uncover the underlying etiology should be initiated as adverse fetal outcomes are sometimes associated with these variations from normalcy.

[Management of post-term pregnancies: the role for AFI, biophysical score and doppler]

OBJECTIVE

To evaluate the role of ultrasound and doppler assessment in the management of prolonged pregnancies and to state its modalities.

METHOD

Medline, PubMed, embase and the Cochrane library were searched using terms prolonged pregnancy, post date pregnancy amniotic fluid, ultrasound assessment, doppler, biophysical profile.

RESULTS

Single deepest vertical pool measurement is the method of choice of the assessment of amniotic fluid. Indeed, when this method was used, significantly fewer case of oligohydramnios were diagnosed and fewer women had inductions of labor. However, this method is not superior to the amniotic fluid index in the prevention of poor perinatal outcomes. There is a significant difference in the incidence of fetal distress, meconium stained fluid and caesarean section for fetal distress when the amniotic fluid is reduced as compared with normal amniotic fluid. However, sensibility and predictive positive value of oligohydramnios to predict poor perinatal outcomes is moderate. Similary, in most studies, diagnosis of an abnormal uterine, umbilical, aortic or cerebral blood flow doppler was associated with a weak prediction of a poor perinatal outcome. Therefore, we do not recommend its use in management of prolonged pregnancy. There were significantly more diagnosis of oligoamnios and more abnormal antenatal monitoring results in the modified biophysical profile group as compared with the group managed with only single deepest pool but no differences in cord blood gases, neonatal outcome, or in outcomes related to labour and delivery were noted between the two groups. Therefore, biophysical profile including AFI offers no advantage in detecting adverse outcomes and may cause more interventions.

CONCLUSION

Close monitoring of fetal condition including assessment of amniotic fluid by single deepest pool twice a week from 41 weeks of gestation is recommended in the management of prolonged pregnancy. Induction of labor could be considered when oligohydramnios is diagnosed by single deepest pool less than 2 cm.

Management of oligohydramnios in pregnancy

The finding of oligohydramnios in pregnancy is problematic. The various mechanisms that control amniotic fluid, the inability to precisely measure and quantify the amount, and the relevance of a "decreased" amount of fluid make the management of this finding unclear. Given the limited amount of data, the single deepest vertical pocket may be a better method than the amniotic fluid index to define oligohydramnios. A large prospective study is needed to develop the most optimal management recommendations, especially for idiopathic oligohydramnios at or near term.

Does diurnal rhythm have an impact on fetal biophysical profile?

OBJECTIVES

To investigate whether parameters in fetal biophysical profile (BPP) testing exhibit a diurnal rhythm and to discuss the probable factors associated with these variables.

METHODS

Thirty healthy primigravid patients carrying pregnancies between 35 and 40 completed weeks were enrolled for the study. Fetal BPP testing was performed for each patient both in the early morning (08:00-10:00 am) and in the late evening (08:00-10:00 pm), and the scoring parameters were compared between morning and evening tests.

RESULTS

BPP scores in the evening were significantly higher than that in the morning (p < 0.05). Deepest vertical amniotic pocket measurements and fetal breathing absence in the morning mostly contributed to this variation (p < 0.001). Fetal movement counts were also significantly lower in the morning tests (p < 0.001).

CONCLUSIONS

The parameters of BPP exhibit circadian variations in healthy fetuses, which may be associated with many factors such as fetomaternal hormones. It is essential for the clinician to be aware of these changes when interpreting the results, as interventions based on false-positive results may have deleterious effects on both the mother and her fetus.

Antepartum fetal testing: a critical appraisal

PURPOSE OF REVIEW

Recognition of the fetus at risk for death or damage in utero, quantifying the risk, balancing fetal risk against the risk of neonatal complications from immaturity and determining optimal time and mode of intervention, is a cornerstone of modern perinatal medicine. Antepartum fetal testing is essential in making these crucial decisions. The art and science of fetal assessment is fluid. In this treatise, the evolution of testing is reviewed, test accuracy results examined and suggestions for future applications are considered.

RECENT FINDINGS

Composite testing of a range of fetal biophysical variables is an excellent predictor of fetal acidemia and risk of death or damage. Confusion regarding the optimal means of measuring one of these variables, amniotic fluid volume, has been addressed in the literature and contemporary studies from several independent sources indicate that the amniotic fluid index method should be abandoned in favor of the maximal vertical pocket method. It is becoming increasingly more evident that a spectrum of fetal testing modalities based on interrogation of different aspects of fetal adaptive responses to adversity is preferable in fetal testing. Further it is evident that in some fetal diseases, such as intrauterine growth restriction, fetal condition may change acutely and accordingly best outcome is achieved by much more frequent testing. The question of whether intervention for fetal compromise can prevent subsequent neurological sequelae remains open.

SUMMARY

There has been remarkable advancement in identifying the fetus at risk. The concept of multispectral combined fetal testing including acute biophysical variables, amniotic fluid volume and arterial and venous Doppler flow velocity waveforms is established.