Definition and management of fetal growth restriction: a survey of contemporary attitudes

Second Trimester Amniotic Fluid Angiotensinogen Levels Linked to Increased Fetal Birth Weight and Shorter Gestational Age in Term Pregnancies

BACKGROUND

Despite the considerable progress made in recent years in fetal assessment, the etiology of fetal growth disturbances is not as yet well understood. In an effort to enhance our knowledge in this area, we investigated the associations of the amniotic fluid angiotensinogen of the renin-angiotensin system with fetal growth abnormalities.

METHODS

We collected amniotic fluid samples from 70 pregnant women who underwent amniocentesis during their early second trimester. Birth weight was documented upon delivery, after which the embryos corresponding to the respective amniotic fluid samples were categorized into three groups as follows: small for gestational age (SGA), appropriate for gestational age (AGA), and large for gestational age (LGA). Amniotic fluid angiotensinogen levels were determined by using ELISA kits.

RESULTS

Mean angiotensinogen values were 3885 ng/mL (range: 1625-5375 ng/mL), 4885 ng/mL (range: 1580-8460 ng/mL), and 4670 ng/mL (range: 1995-7250 ng/mL) in the SGA, LGA, and AGA fetuses, respectively. The concentrations in the three groups were not statistically significantly different. Although there were wide discrepancies between the mean values of the subgroups, the large confidence intervals in the three groups negatively affected the statistical analysis. However, multiple regression analysis revealed a statistically significant negative correlation between the angiotensinogen levels and gestational age and a statistically significant positive correlation between the birth weight and angiotensinogen levels.

DISCUSSION

Our findings suggest that fetal growth abnormalities did not correlate with differences in the amniotic fluid levels of angiotensinogen in early second trimester pregnancies. However, increased angiotensinogen levels were found to be consistent with a smaller gestational age at birth and increased BMI of neonates.

Fetal Thymus Size at 19-22 Weeks of Gestation: A Possible Marker for the Prediction of Low Birth Weight?

INTRODUCTION

The purpose was to compare thymus size measured during second trimester screening of fetuses who were subsequently small for gestational age at birth (weight below 10th percentile, SGA group) with fetuses with normal birth weight (control group). We hypothesized that measuring the fetal thymic-thoracic ratio (TT-ratio) might help predict low birth weight.

METHODS

Using three-vessel view echocardiograms from our archives, we measured the anteroposterior thymus size and the intrathoracic mediastinal diameter to derive TT-ratios in the SGA (n = 105) and control groups (n = 533) between 19+0 and 21+6 weeks of gestation. We analyzed the association between TT-ratio and SGA adjusted to the week of gestation using logistic regression. Finally, we determined the possible TT-ratio cut-off point for discrimination between SGA and control groups by means of receiver operating characteristics (ROC) curve analysis.

RESULTS

The TT-ratio was significantly higher in the SGA group than in the control group (p < 0.001). An increase of the TT-ratio by 0.1 was associated with a 3.1-fold increase in the odds of diagnosing SGA. We determined that a possible discrimination cut-off point between SGA and healthy controls was achieved using a TT-ratio of 0.390 (area under the ROC curve 0.695).

CONCLUSION

An increased TT-ratio may represent an additional prenatal screening parameter that improves the prediction of birth weight below the 10th percentile. Prospective studies are now needed to evaluate the use of fetal thymus size as predictive parameter for adverse fetal outcome.

Is There a Correlation between Apelin and Insulin Concentrations in Early Second Trimester Amniotic Fluid with Fetal Growth Disorders?

INTRODUCTION

Fetal growth disturbances place fetuses at increased risk for perinatal morbidity and mortality. As yet, little is known about the basic pathogenetic mechanisms underlying deranged fetal growth. Apelin is an adipokine with several biological activities. Over the past decade, it has been investigated for its possible role in fetal growth restriction. Most studies have examined apelin concentrations in maternal serum and amniotic fluid in the third trimester or during neonatal life. In this study, apelin concentrations were examined for the first time in early second-trimester fetuses. Another major regulator of tissue growth and metabolism is insulin.

MATERIALS AND METHODS

This was a prospective observational cohort study. We measured apelin and insulin concentrations in the amniotic fluid of 80 pregnant women who underwent amniocentesis in the early second trimester. Amniotic fluid samples were stored in appropriate conditions until delivery. The study groups were then defined, i.e., gestations with different fetal growth patterns (SGA, AGA, and LGA). Measurements were made using ELISA kits.

RESULTS

Apelin and insulin levels were measured in all 80 samples. The analysis revealed statistically significant differences in apelin concentrations among groups (p = 0.007). Apelin concentrations in large for gestational age (LGA) fetuses were significantly lower compared to those in AGA and SGA fetuses. Insulin concentrations did not differ significantly among groups.

CONCLUSIONS

A clear trend towards decreasing apelin concentrations as birthweight progressively increased was identified. Amniotic fluid apelin concentrations in the early second trimester may be useful as a predictive factor for determining the risk of a fetus being born LGA. Future studies are expected/needed to corroborate the present findings and should ideally focus on the potential interplay of apelin with other known intrauterine metabolic factors.

Perinatal Adverse Effects in Newborns with Estimated Loss of Weight Percentile between the Third Trimester Ultrasound and Delivery. The GROWIN Study

Fetal growth restriction has been associated with an increased risk of adverse perinatal outcomes (APOs). We determined the importance of fetal growth detention (FGD) in late gestation for the occurrence of APOs in small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA) newborns. For this purpose, we analyzed a retrospective cohort study of 1067 singleton pregnancies. The newborns with higher APOs were SGA non-FGD and SGA FGD in 40.9% and 31.5% of cases, respectively, and we found an association between SGA non-FGD and any APO (OR 2.61; 95% CI: 1.35–4.99; p = 0.004). We did not find an increased APO risk in AGA FGD newborns (OR: 1.13, 95% CI: 0.80, 1.59; p = 0.483), except for cesarean delivery for non-reassuring fetal status (NRFS) with a decrease in percentile cutoff greater than 40 (RR: 2.41, 95% CI: 1.11–5.21) and 50 (RR: 2.93, 95% CI: 1.14–7.54). Conclusions: Newborns with the highest probability of APOs are SGA non-FGDs. AGA FGD newborns do not have a higher incidence of APOs than AGA non-FGDs, although with falls in percentile cutoff over 40, they have an increased risk of cesarean section due to NRFS. Further studies are warranted to detect these newborns who would benefit from close surveillance in late gestation and at delivery.

Cerebroplacental doppler ratio and perinatal outcome in late-onset foetal growth restriction

The purpose of this study was to determine whether gestational age-specific levels of the cerebroplacental ratio (CPR) as a third-trimester ultrasound marker has benefits in the prediction of perinatal morbidity and mortality on foetuses with late-onset foetal growth restriction (FGR). A retrospective study of singleton pregnancies diagnosed with late-onset FGR was performed. Of 407 pregnancies meeting our inclusion criteria, 313 had normal (Group 1) and 94 had abnormal CPR (Group 2). Both groups were similar in age, gestational age at diagnosis, body mass index and parity. There was a significant association between the presence of oligohydramnios and abnormal CPR. Mean gestational age at delivery and mean neonatal birth weight were significantly lower in Group 2. Neonatal intensive care unit admission, foetal distress, low 5-minute Apgar score <7, and low cord pH < 7.1 rates were significantly higher in Group 2. There was one neonatal death in both groups. Multivariable regression analysis demonstrated that, in the prediction of APO, there was a significant contribution from neonatal birth weight <10th percentile, CPR <5th percentile and oligohydramniosis. Our findings revealed that CPR value less than 5th centile can be used as a predictor of APO in late-onset FGR.IMPACT STATEMENTWhat is already known on this subject? Low cerebroplacetal ratio (CPR) is a marker of failure to reach the growth potential regardless of foetal weight.What do the results of this study add? The CPR can be used as an adequate predictor of adverse perinatal outcome in pregnancies with late-onset foetal growth restriction.What are the implications of these findings for clinical practice and/or further research? Routine calculation and report of CPR during basic ultrasound examination may help to identify foetuses with FR with a higher risk of adverse perinatal outcome. Future prospective studies on pregnancies with FGR with oligohydroamnios or normal amniotic fluid volume should focus on determining CPR threshold.

Clinical monitoring of late fetal growth restriction

Late fetal growth restriction (FGR) poses its own challenges in respect of diagnosis, surveillance and delivery timing. Perinatal morbidity is relatively rare, and mortality extremely unusual, but given that late FGR is much more frequent than early FGR, the burden on neonatal services must not be underestimated. Doppler findings are more subtle than in early FGR, and growth rate rather than absolute fetal size may be important in defining the condition. Though umbilical artery Doppler changes form the basis for triggering delivery: reversed end diastolic flow at 32 weeks, absent at 34 weeks and raised PI at 36 weeks, other modalities of monitoring - for example cardiotocography and cerebral Doppler - are important in surveillance and timing follow up of the condition.

Fetal Growth Diagnosis and Management among Perinatal Medical Professionals: A Survey of Practice and Literature Review

INTRODUCTION

This paper aimed to assess the knowledge of healthcare professionals (obstetric and gynecology residents, specialists, and midwives) in the field of perinatal medicine regarding fetal growth diagnosis and management.

METHODS

A questionnaire was created consisting of a set of questions regarding demographic data, methods of growth assessment, and management. It was a handout survey. The results were analyzed with the use of descriptive statistics and χ2 analysis using the program Statistica.

RESULTS

190 medical professionals have participated in the questionnaire. 86.3% of respondents agreed that pregnancy dating should be modified based on first-trimester ultrasound. 90.9% agreed that III trimester ultrasound has a ±15% margin of error. When asked which growth charts are best fit for assessing growth in a studied population, 10.7% marked standard, 37.4% reference, 26.2% customized, and 26.2% did not know the difference between the three choices. 60.3% stated that they use a growth chart to assess growth and qualify fetuses for monitoring. 70.2% used the 10th centile as a cutoff, 20.1% 5th centile, and 9.7% 3rd centile. Only 40.9% would diagnose fetal growth restriction based on fetal weight only. 28.7% using the 10th centile cutoff, 16.1% 5th centile, and 54.0% 3rd centile. Only a quarter of the respondents were able to name the growth chart or tool that they use for assessment. The most common responses were Yudkin, Hadlock, and online calculators of Fetal Medicina Barcelona and the Fetal Medicine Foundation.

DISCUSSION

A lot of confusion is observed primarily in the aspect of cutoff values for identification, subsequent monitoring, and management of fetal growth restriction. There is a need for extensive training and education in this field and uniform national recommendations.

Society for Maternal-Fetal Medicine Consult Series #52: Diagnosis and management of fetal growth restriction: (Replaces Clinical Guideline Number 3, April 2012)

Fetal growth restriction can result from a variety of maternal, fetal, and placental conditions. It occurs in up to 10% of pregnancies and is a leading cause of infant morbidity and mortality. This complex obstetrical problem has disparate published diagnostic criteria, relatively low detection rates, and limited preventative and treatment options. The purpose of this Consult is to outline an evidence-based, standardized approach for the prenatal diagnosis and management of fetal growth restriction. The recommendations of the Society for Maternal-Fetal Medicine are as follows: (1) we recommend that fetal growth restriction be defined as an ultrasonographic estimated fetal weight or abdominal circumference below the 10th percentile for gestational age (GRADE 1B); (2) we recommend the use of population-based fetal growth references (such as Hadlock) in determining fetal weight percentiles (GRADE 1B); (3) we recommend against the use of low-molecular-weight heparin for the sole indication of prevention of recurrent fetal growth restriction (GRADE 1B); (4) we recommend against the use of sildenafil or activity restriction for in utero treatment of fetal growth restriction (GRADE 1B); (5) we recommend that a detailed obstetrical ultrasound examination (current procedural terminology code 76811) be performed with early-onset fetal growth restriction (<32 weeks of gestation) (GRADE 1B); (6) we recommend that women be offered fetal diagnostic testing, including chromosomal microarray analysis, when fetal growth restriction is detected and a fetal malformation, polyhydramnios, or both are also present regardless of gestational age (GRADE 1B); (7) we recommend that pregnant women be offered prenatal diagnostic testing with chromosomal microarray analysis when unexplained isolated fetal growth restriction is diagnosed at <32 weeks of gestation (GRADE 1C); (8) we recommend against screening for toxoplasmosis, rubella, or herpes in pregnancies with fetal growth restriction in the absence of other risk factors and recommend polymerase chain reaction for cytomegalovirus in women with unexplained fetal growth restriction who elect diagnostic testing with amniocentesis (GRADE 1C); (9) we recommend that once fetal growth restriction is diagnosed, serial umbilical artery Doppler assessment should be performed to assess for deterioration (GRADE 1C); (10) with decreased end-diastolic velocity (ie, flow ratios greater than the 95th percentile) or in pregnancies with severe fetal growth restriction (estimated fetal weight less than the third percentile), we suggest weekly umbilical artery Doppler evaluation (GRADE 2C); (11) we recommend Doppler assessment up to 2-3 times per week when umbilical artery absent end-diastolic velocity is detected (GRADE 1C); (12) in the setting of reversed end-diastolic velocity, we suggest hospitalization, administration of antenatal corticosteroids, heightened surveillance with cardiotocography at least 1-2 times per day, and consideration of delivery depending on the entire clinical picture and results of additional evaluation of fetal well-being (GRADE 2C); (13) we suggest that Doppler assessment of the ductus venosus, middle cerebral artery, or uterine artery not be used for routine clinical management of early- or late-onset fetal growth restriction (GRADE 2B); (14) we suggest weekly cardiotocography testing after viability for fetal growth restriction without absent/reversed end-diastolic velocity and that the frequency be increased when fetal growth restriction is complicated by absent/reversed end-diastolic velocity or other comorbidities or risk factors (GRADE 2C); (15) we recommend delivery at 37 weeks of gestation in pregnancies with fetal growth restriction and an umbilical artery Doppler waveform with decreased diastolic flow but without absent/reversed end-diastolic velocity or with severe fetal growth restriction with estimated fetal weight less than the third percentile (GRADE 1B); (16) we recommend delivery at 33-34 weeks of gestation for pregnancies with fetal growth restriction and absent end-diastolic velocity (GRADE 1B); (17) we recommend delivery at 30-32 weeks of gestation for pregnancies with fetal growth restriction and reversed end-diastolic velocity (GRADE 1B); (18) we suggest delivery at 38-39 weeks of gestation with fetal growth restriction when the estimated fetal weight is between the 3rd and 10th percentile and the umbilical artery Doppler is normal (GRADE 2C); (19) we suggest that for pregnancies with fetal growth restriction complicated by absent/reversed end-diastolic velocity, cesarean delivery should be considered based on the entire clinical scenario (GRADE 2C); (20) we recommend the use of antenatal corticosteroids if delivery is anticipated before 33 6/7 weeks of gestation or for pregnancies between 34 0/7 and 36 6/7 weeks of gestation in women without contraindications who are at risk of preterm delivery within 7 days and who have not received a prior course of antenatal corticosteroids (GRADE 1A); and (21) we recommend intrapartum magnesium sulfate for fetal and neonatal neuroprotection for women with pregnancies that are <32 weeks of gestation (GRADE 1A).

Fetal Growth Restriction - Diagnostic Work-up, Management and Delivery

Fetal or intrauterine growth restriction (FGR/IUGR) affects approximately 5 – 8% of all pregnancies and refers to a fetus not exploiting its genetically determined growth potential. Not only a major cause of perinatal morbidity and mortality, it also predisposes these fetuses to the development of chronic disorders in later life. Apart from the timely diagnosis and identification of the causes of FGR, the obstetric challenge primarily entails continued antenatal management with optimum timing of delivery. In order to minimise premature birth morbidity, intensive fetal monitoring aims to prolong the pregnancy and at the same time intervene, i.e. deliver, before the fetus is threatened or harmed. It is important to note that early-onset FGR (< 32 + 0 weeks of gestation [wks]) should be assessed differently than late-onset FGR (≥ 32 + 0 wks). In early-onset FGR progressive deterioration is reflected in abnormal venous Doppler parameters, while in late-onset FGR this manifests primarily in abnormal cerebral Doppler ultrasound. According to our current understanding, the “optimum” approach for monitoring and timing of delivery in early-onset FGR combines computerized CTG with the ductus venosus Doppler, while in late-onset FGR assessment of the cerebral Doppler parameters becomes more important.

Use of birth weight- vs. ultrasound-derived fetal weight classification methods: implications for detection of abnormal umbilical artery Doppler

Objectives To compare a birth weight-derived (Brenner) and multiple ultrasound-derived [Hadlock, National Institute of Child Health and Human Development (NICHD), International Fetal and Newborn Growth Consortium (INTERGROWTH)] classification systems' frequency of assigning an antenatal estimated fetal weight (EFW) <10% and subsequent detection rate for abnormal umbilical artery Doppler (UAD). Methods We analyzed 569 consecutive non-anomalous singleton gestations identified by ultrasound with either an abdominal circumference (AC) <3% or EFW <10% at a tertiary medical center between 1/2012 and 12/2016. The biometric measurements were exported for all serial ultrasounds and the sensitivity, specificity, positive and negative predictive values, and area under the curve (AUC) were calculated for the diagnosis of any abnormal UAD, absent or reversed end-diastolic flow (AREDF), and small for gestational age (SGA) for each classification method. Results Brenner classified less patients with EFW <10% (49.7%) vs. the comparison methods (range: 84.2-85.0%; P < 0.001). The sensitivity was highest using Hadlock for detection of any abnormal UAD [96.6%; confidence interval (CI) 92.8-98.8%], AREDF (100%; CI 95.1-100%), and SGA (89.0%; CI 85.4-91.6%). However, there was minimal variation between the Hadlock, NICHD, and INTERGROWTH methods for detection of the studied outcomes. The AUCs for any abnormal UAD, AREDF, and SGA were highest for the Brenner method, but there were a substantial number of false-negative results with lower overall detection rates. Conclusions Use of a birth weight-derived method to assign a fetal weight <10% as the threshold to initiate UAD surveillance has a lower detection rate for abnormal UAD when compared to ultrasound-derived methods. Despite substantial methodological differences in the creation of the Hadlock, NICHD, and INTERGROWTH methods, there were no differences in the detection rates of abnormal UAD.

Long-term follow-up on fetuses with isolated sonographic finding of short long bones: a cohort study

PURPOSE

To evaluate the long-term outcome of fetuses with a diagnosis of isolated short long bones.

METHODS

A retrospective review was conducted of all cases diagnosed with short long bones above 20 weeks of gestation during 2010-2017 in a single tertiary center. Exclusion criteria included abnormal sonographic findings other than short long bones, suspected genetic syndromes, chromosomal abnormalities, and abnormal Doppler flow indices. Follow-up was carried out by telephone questionnaire.

RESULTS

During the study period, 54 (24.32%) women met inclusion criteria. Mean gestational age at delivery was 38.05 years (± 2.42 SD). Mean birth weight was 12-19th percentile according to the local fetal growth charts [2645 g (± 684 SD) 95% CI 2173-2980]. Median time for post-natal follow-up was 9.3 years (IQR 6.6-10.75). Growth below the 10th percentile was demonstrated in 27 (50%) children. 11 (20.37%) children were followed up by endocrinological clinics, of them 7 (12.96%) were treated with growth hormone. Three (5.6%) of the children were diagnosed with attention deficit hyperactivity disorder, an incidence that is considered lower than that of the general population (± 9%).

CONCLUSIONS

Prenatal fetal isolated short long bones diagnosed during the late second and third trimester is associated with short stature. No neurodevelopmental impact was observed in our study group.

Perinatal outcome of appropriate-weight fetuses with decelerating growth

INTRODUCTION

To assess the perinatal outcome of fetuses dropping by ≥50 estimated fetal weight (EFW) centiles between the second and third trimester.

METHODS

Singleton pregnancies progressing after 32 + 0 weeks, who had their second- and third-trimester scans at our institutions were enrolled in the study. The perinatal outcome of AGA fetuses crossing more than 50 centiles was compared to that of fetuses with FGR, small for gestational age (SGA) and nondecelerating appropriate for gestational age (AGA). The primary perinatal outcomes were perinatal death, neonatal intensive care (NICU) admission and emergency cesarean section (CS). The rates of these outcomes were compared between the four groups and regression analysis was performed to account for maternal and fetal confounders.

RESULTS

Our analysis included 4394 cases. Compared to nondecelerating SGA, fetuses crossing ≥50 centiles had higher rates of NICU admission (odds ratio [OR] 1.8, 95% confidence interval [CI] CI 1.1-3.1) and perinatal death (OR 3.8, 95%CI 1.3-11.4). Regression analysis showed that significant independent predictors for NICU admission included maternal age, gestational age at birth and FGR (area under the curve [AUC] 0.851), whereas significant predictors for perinatal death included maternal age, gestational age at birth, decelerating growth ≥50 centiles, conception through ART and third-trimester CPR centile (AUC 0.801).

CONCLUSION

AGA fetuses that cross >50 EFW centiles between the second and third trimester are at increased risk of adverse perinatal outcome and it seems advisable that they are followed up as typical FGR cases.

Fetal growth restriction: From Polyvagal theory to developmental impairments?

BACKGROUND

The Polyvagal theory argues that behavioral modulation is a fundamental neurodevelopmental process that depends on autonomic regulation.

OBJECTIVE

The present study aimed to assess sleep architecture in newborns with fetal growth restriction (FGR) using polysomnography as an indicator of Polyvagal theory.

METHODS

We studied polysomnography recordings from 68 preterm infants, 34 with FGR and 34 born with appropriate growth for gestational age (AGA), who were matched according to the corrected age for prematurity (CA). Total sleep time, arousals, the percentage of quiet sleep, active sleep, indeterminate sleep, and heart rate were compared between the groups. Linear multiple regression analyses were used to evaluate polysomnography data for the FGR and AGA groups.

RESULTS

Average heart rate was significantly lower in most FGR groups compared with AGA groups, and small to large effect sizes were observed in several sleep responses when comparing these groups. In the lineal regression model the CA explains significantly the differences in heart rate, controlled by FGR (p = .012). Additionally, there was evidence that sleeping states show similar trends, that is, increases in quiet and indeterminate sleep, as well as decreases in active sleep when CA was controlled by FGR.

CONCLUSION

FGR probably intensifies the unfavorable effect of preterm birth in the responses evaluated by polysomnography. It seems that FGR is associated with alteration in sleep regulation and with differences in heart rate modulation, which may serve as a strategy to preserve energy and such differences likely underlie neurodevelopmental impairments in affected newborns.

Customised birthweight standard for a Slovenian population

Objective To produce a customised birthweight standard for Slovenia. Methods This retrospective study used a cohort from the National Perinatal Information System of Slovenia (NPIS). Prospectively collected information from pregnancies delivered in all of Slovenia's 14 maternal hospitals between 1st January 2003 and 31st December 2012 was included. Coefficients were derived using a backward stepwise multiple regression technique. Results A total of 126,627 consecutive deliveries with complete data were included in the multivariable analysis. Maternal height, weight in early pregnancy and parity as well as the baby's sex were identified as physiological variables, with coefficients comparable to findings in other countries. The expected 280-day birthweight, free from pathological influences, of a standard size mother (height 163 cm, weight 64 kg) in her first pregnancy was 3451.3 g. Pathological influences on birthweight within this population included low and high maternal age, low and high body mass index (BMI), smoking, pre-existing and gestational diabetes and pre-existing and gestational hypertension. Conclusion The analysis confirmed the main physiological variables that affect birthweight in studies from other countries, and was able to quantify additional pathological factors of maternal age and gestational diabetes. Development of a country-specific customised birthweight standard will aid clinicians in Slovenia with the distinction between normal and abnormal small-for-gestational age (SGA) fetuses, thus avoiding unnecessary interventions and improving identification of at risk pregnancies, and long-term outcomes for infants.

Neurodevelopmental outcomes at five years after early-onset fetal growth restriction: Analyses in a Dutch subgroup participating in a European management trial

OBJECTIVE

The objective of this study is to explore developmental outcomes at five years after early-onset fetal growth restriction (FGR).

STUDY DESIGN

Retrospective data analysis of prospective follow-up of patients of three Dutch centres, who participated in a twenty centre European randomized controlled trial on timing of delivery in early-onset FGR. Developmental outcome of very preterm infants born after extreme FGR is assessed at (corrected) age of five.

RESULTS

Seventy-four very preterm FGR children underwent follow-up at the age of five. Mean gestational age at birth was 30 weeks and birth weight was 910 g, 7% had a Bayley score <85 at two years. Median five years' FSIQ was 97, 16% had a FSIQ < 85, and 35% had one or more IQ scores <85. Motor score ≤ 7 on movement ABC-II (M-ABC-II-NL) was seen in 38%. Absent or reversed end-diastolic flow, gestational age at delivery, birthweight and neonatal morbidity were related to an FSIQ < 85. Any abnormal IQ scale score was related to birthweight, male sex and severity of FGR, and abnormal motor score to male sex and bronchopulmonary dysplasia (BPD).

CONCLUSIONS

Overall, median cognitive outcome at five years was within normal range, but 35% of the children had any abnormal IQ score at age five, depending on the IQ measure, and motor impairment was seen in 38% of the children. GA at delivery, birthweight, EDF prior to delivery and neonatal morbidity were the most important risk factors for cognitive outcomes.

Metabolomics of Pregnancy Complications: Emerging Application of Maternal Hair

In recent years, the study of metabolomics has begun to receive increasing international attention, especially as it pertains to medical research. This is due in part to the potential for discovery of new biomarkers in the metabolome and to a new understanding of the "exposome", which refers to the endogenous and exogenous compounds that reflect external exposures. Consequently, metabolomics research into pregnancy-related issues has increased. Biomarkers discovered through metabolomics may shed some light on the etiology of certain pregnancy-related complications and their adverse effects on future maternal health and infant development and improve current clinical management. The discoveries and methods used in these studies will be compiled and summarized within the following paper. A further focus of this paper is the use of hair as a biological sample, which is gaining increasing attention across diverse fields due to its noninvasive sampling method and the metabolome stability. Its significance in exposome studies will be considered in this review, as well as the potential to associate exposures with adverse pregnancy outcomes. Currently, hair has been used in only two metabolomics studies relating to fetal growth restriction (FGR) and gestational diabetes mellitus (GDM).

Association between Brain-Derived Neurotrophic Factor (BDNF) Levels in 2nd Trimester Amniotic Fluid and Fetal Development

The development of the fetal nervous system mirrors general fetal development, comprising a combination of genetic resources and effects of the intrauterine environment. Our aim was to assess the 2^nd trimester amniotic fluid levels of brain-derived neurotrophic factor (BDNF) and to investigate its association with fetal growth. In accordance with our study design, samples of amniotic fluid were collected from women who had undergone amniocentesis early in the 2^nd trimester. All pregnancies were followed up until delivery and fetal growth patterns and birth weights were recorded, following which pregnancies were divided into three groups based on fetal weight: (1) AGA (appropriate for gestational age), (2) SGA (small for gestational age), and (3) LGA (large for gestational age). We focused on these three groups representing a reflection of the intrauterine growth spectrum. Our results revealed the presence of notably higher BDNF levels in the amniotic fluid of impaired growth fetuses by comparison with those of normal growth. Both SGA and macrosomic fetuses are characterized by notably higher amniotic fluid levels of BDNF (mean values of 36,300 pg/ml and 35,700 pg/ml, respectively) compared to normal-growth fetuses (mean value of 32,700 pg/ml). Though apparently small, this difference is, nevertheless, statistically significant (p value < 0.05) in SGA fetuses in the extremes of the distribution, i.e., below the 3rd centile. In conclusion, there is clear evidence that severe impairment of fetal growth induces the increased production of fetal brain growth factor as an adaptive mechanism in reaction to a hostile intrauterine environment, thereby accelerating fetal brain development and maturation.

Predictive accuracy of cerebroplacental ratio for adverse perinatal and neurodevelopmental outcomes in suspected fetal growth restriction: systematic review and meta-analysis

OBJECTIVE

The cerebroplacental ratio (CPR) has been proposed for the routine surveillance of pregnancies with suspected fetal growth restriction (FGR), but the predictive performance of this test is unclear. The aim of this study was to determine the accuracy of CPR for predicting adverse perinatal and neurodevelopmental outcomes in suspected FGR.

METHODS

PubMed, EMBASE, CINAHL and Lilacs were searched from inception to 31 July 2017 for cohort or cross-sectional studies reporting on the accuracy of CPR for predicting adverse perinatal and/or neurodevelopmental outcomes in singleton pregnancies with FGR suspected antenatally based on sonographic parameters. Summary receiver-operating characteristics (ROC) curves, pooled sensitivities and specificities, and summary likelihood ratios (LRs) were generated.

RESULTS

Twenty-two studies (including 4301 women) met the inclusion criteria. Summary ROC curves showed that the best predictive accuracy of CPR was for perinatal death and the worst was for neonatal acidosis, with areas under the summary ROC curves of 0.83 and 0.57, respectively. The predictive accuracy of CPR was moderate to high for perinatal death (pooled sensitivity and specificity of 93% and 76%, respectively, and summary positive and negative LRs of 3.9 and 0.09, respectively) and low for composite of adverse perinatal outcomes, Cesarean section for non-reassuring fetal status, 5-min Apgar score < 7, admission to the neonatal intensive care unit, neonatal acidosis and neonatal morbidity, with summary positive and negative LRs ranging from 1.1 to 2.5 and 0.3 to 0.9, respectively. An abnormal CPR result had moderate accuracy for predicting small-for-gestational age at birth (summary positive LR of 7.4). CPR had a higher predictive accuracy in pregnancies with suspected early-onset FGR. No study provided data for assessing the predictive accuracy of CPR for adverse neurodevelopmental outcome.

CONCLUSION

CPR appears to be useful in predicting perinatal death in pregnancies with suspected FGR. Nevertheless, before incorporating CPR into the routine clinical management of suspected FGR, randomized controlled trials should assess whether the use of CPR reduces perinatal death or other adverse perinatal outcomes. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Impact of Intrauterine Growth Restriction on Cognitive and Motor Development at 2 Years of Age

Intrauterine growth restriction (IUGR), which is already known to be a risk factor for pathological intrauterine development, perinatal mortality, and morbidity, is now also assumed to cause both physical and cognitive alterations in later child development. In the current study, effects of IUGR on infantile brain function were investigated during the fetal period and in a follow-up developmental assessment during early childhood. During the fetal period, visual and auditory event-related responses (VER and AER) were recorded using fetal magnetoencephalography (fMEG). VER latencies were analyzed in 73 fetuses (14 IUGR fetuses) while AER latencies were analyzed in 66 fetuses (11 IUGR fetuses). Bayley Scales of Infant Development, Second Edition (BSID-II) were used to assess the developmental status of the infants at the age of 24 months. The Mental Development Index (MDI) was available from 66 children (8 IUGR fetuses) and the Psychomotor Development Index (PDI) from 63 children (7 IUGR fetuses). Latencies to visual stimulation were more delayed in IUGR than in small for gestational age (SGA) or appropriate for gestational age (AGA) fetuses, albeit not to any significant extent (p = 0.282). The MDI in former IUGR infants was significantly lower (p = 0.044) than in former SGA and AGA infants. However, IUGR had no impact on PDI (p = 0.213). These findings support the hypothesis that IUGR may constitute a risk factor for neurodevelopmental delay. Further investigation of the possible underlying mechanisms, as well as continued long-term developmental research, is therefore necessary.

Longitudinal Trajectories of Gestational Thyroid Function: A New Approach to Better Understand Changes in Thyroid Function

CONTEXT

Most studies of thyroid function changes during pregnancy use a cross-sectional design comparing means between groups rather than similarities within groups.

OBJECTIVE

Latent class growth analysis (LCGA) is a novel approach to investigate longitudinal changes that provide dynamic understanding of the relationship between thyroid status and advancing pregnancy.

DESIGN

Prospective observational study with repeated assessments.

SETTING

General community.

PATIENTS

Eleven hundred healthy women were included at 12 weeks' gestation.

MAIN OUTCOME MEASURES

The existence of both free T4 (fT4) and TSH trajectories throughout pregnancy determined by LCGA.

RESULTS

LCGA revealed three trajectory classes. Class 1 (n = 1019; 92.4%), a low increasing TSH reference group, had a gradual increase in TSH throughout gestation (from 1.1 to 1.3 IU/L). Class 2 (n = 30; 2.8%), a high increasing TSH group, displayed the largest increase in TSH (from 1.9 to 3.3 IU/L). Class 3 (n = 51; 4.6%), a decreasing TSH group, had the largest fall in TSH (from 3.2 to 2.4 IU/L). Subclinical hypothyroidism at 12 weeks occurred in up to 60% of class 3 women and was accompanied by elevated thyroid peroxidase antibodies (TPO-Ab) titers (50%) and a parental history of thyroid dysfunction (23%). In class 2, 70% of women were nulliparous compared with 46% in class 1 and 49% in class 3.

CONCLUSIONS

LCGA revealed distinct trajectories of longitudinal changes in fT4 and TSH levels during pregnancy in 7.4% of women. These trajectories were correlated with parity and TPO-Ab status and followed patterns that might reflect differences in pregnancy-specific immune tolerance between nulliparous and multiparous women.

Examining the link between placental pathology, growth restriction, and stillbirth

Stillbirth, often defined as death of a fetus ≥20 weeks of gestation, is emotionally devastating for families and caregivers. It is often associated with fetal growth restriction (FGR). Indeed, FGR or small-for-gestational age fetus (SGA) is a major risk factor for stillbirth. In rare cases, this is due to genetic abnormalities or infections. However, in most cases, it is linked to placental insufficiency. This may be due to abnormal placental development or placental damage, thereby resulting in decreased blood flow, oxygen, and nutrients to the fetus. Several placental histological abnormalities are associated with stillbirth, FGR, or both. Most involve vascular abnormalities but some are inflammatory lesions. This paper reviews evidence regarding the relationships between placental function and pathology, FGR, and stillbirth. Issues with clinical relevance, knowledge gaps, and areas for further research are highlighted.

Building consensus and standards in fetal growth restriction studies

Fetal growth restriction is a pathologic condition in which the fetus fails to reach its biologically based growth potential. There is inconsistency in terminology, definition, monitoring, and management, both in clinical practice and in the existing literature. This hampers interpretation and comparison of cohorts and studies. Standardization is essential. With the lack of a golden standard, or the opportunity to come to empirical evidence, consensus procedures can help to establish standardization. Consensus procedures provide no new information but formulate an agreement (as second best in the absence of robust evidence) for clinical and/or research practice on the basis of existing data. Consensus agreements need to be updated when new evidence becomes available and can change over time. In this chapter, we address the different issues that lack uniformity in FGR studies and management. Furthermore, we discuss several consensus methods and recent consensus procedures regarding fetal growth restriction.

Fetal growth velocity and body proportion in the assessment of growth

Fetal growth restriction implies failure of a fetus to meet its growth potential and is associated with increased perinatal mortality and morbidity. Therefore, antenatal detection of fetal growth restriction is of major importance in an attempt to deliver improved clinical outcomes. The most commonly used approach towards screening for fetal growth restriction is by means of sonographic fetal weight estimation, to detect fetuses small for gestational age, defined by an estimated fetal weight <10th percentile for gestational age. However, the predictive accuracy of this approach is limited both by suboptimal detection rate (as it may overlook non-small-for-gestational-age growth-restricted fetuses) and by a high false-positive rate (as most small-for-gestational-age fetuses are not growth restricted). Here, we review 2 strategies that may improve the diagnostic accuracy of sonographic fetal biometry for fetal growth restriction. The first strategy involves serial ultrasound evaluations of fetal biometry. The information obtained through these serial assessments can be interpreted using several different approaches including fetal growth velocity, conditional percentiles, projection-based methods, and individualized growth assessment that can be viewed as mathematical techniques to quantify any decrease in estimated fetal weight percentile, a phenomenon that many care providers assess and monitor routinely in a qualitative manner. This strategy appears promising in high-risk pregnancies where it seems to improve the detection of growth-restricted fetuses at increased risk of adverse perinatal outcomes and, at the same time, decrease the risk of falsely diagnosing healthy constitutionally small-for-gestational-age fetuses as growth restricted. Further studies are needed to determine the utility of this strategy in low-risk pregnancies as well as to optimize its performance by determining the optimal timing and interval between exams. The second strategy refers to the use of fetal body proportions to classify fetuses as either symmetric or asymmetric using 1 of several ratios; these include the head circumference to abdominal circumference ratio, transverse cerebellar diameter to abdominal circumference ratio, and femur length to abdominal circumference ratio. Although these ratios are associated with small for gestational age at birth and with adverse perinatal outcomes, their predictive accuracy is too low for clinical practice. Furthermore, these associations become questionable when other, potentially more specific measures such as umbilical artery Doppler are being used. Furthermore, these ratios are of limited use in determining the etiology underlying fetal smallness. It is possible that the use of the 2 gestational-age-independent ratios (transverse cerebellar diameter to abdominal circumference and femur length to abdominal circumference) may have a role in the detection of mild-moderate fetal growth restriction in pregnancies without adequate dating. In addition, despite their limited predictive accuracy, these ratios may become abnormal early in the course of fetal growth restriction and may therefore identify pregnancies that may benefit from closer monitoring of fetal growth.

Antenatal glucocorticoids, magnesium sulfate, and mode of birth in preterm fetal small for gestational age

A diagnosis of fetal growth restriction and subsequent preterm birth is associated with increased risks of adverse perinatal and neurodevelopmental outcomes and potentially long-lasting effects to adulthood. Most such cases are associated with placental insufficiency and the fetal response to chronic intrauterine hypoxemia and nutrient deprivation leads to substantial physiological and metabolic adaptations. The management of such pregnancies, especially with respect to perinatal interventions and birth mode, remains an unresolved dilemma. The benefits from standard interventions for threatened preterm birth may not be necessarily translated to pregnancies with small-for-gestational-age fetuses. Clinical trials or retrospective studies on outcomes following administration of antenatal glucocorticoids and magnesium sulfate for neuroprotection when preterm birth is imminent either have yielded conflicting results for small-for-gestational-age fetuses, or did not include this subgroup of patients. Experimental models highlight potential harmful effects of administration of antenatal glucocorticoids and magnesium sulfate in the pregnancies with fetal small for gestational age although clinical data do not substantiate these concerns. In addition, heterogeneity in definitions of fetal small for gestational age, variations in the inclusion criteria, and the glucocorticoid regime contribute to inconsistent results. In this review, we discuss the physiologic adaptions of the small-for-gestational-age fetus to its abnormal in utero environment in relation to antenatal glucocorticoids; the impact of antenatal glucocorticoids and intrapartum magnesium sulfate in pregnancies with fetal small for gestational age; the current literature on birth mode for pregnancies with fetal small for gestational age; and the knowledge gaps in the existing literature.

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.

A Novel Use of Three-dimensional High-frequency Ultrasonography for Early Pregnancy Characterization in the Mouse

High-frequency ultrasonography (HFUS) is a common method to non-invasively monitor the real-time development of the human fetus in utero. The mouse is routinely used as an in vivo model to study embryo implantation and pregnancy progression. Unfortunately, such murine studies require pregnancy interruption to enable follow-up phenotypic analysis. To address this issue, we used three-dimensional (3-D) reconstruction of HFUS imaging data for early detection and characterization of murine embryo implantation sites and their individual developmental progression in utero. Combining HFUS imaging with 3-D reconstruction and modeling, we were able to accurately quantify embryo implantation site number as well as monitor developmental progression in pregnant C57BL6J/129S mice from 5.5 days post coitus (d.p.c.) through to 9.5 d.p.c. with the use of a transducer. Measurements included: number, location, and volume of implantation sites as well as inter-implantation site spacing; embryo viability was assessed by cardiac activity monitoring. In the immediate post-implantation period (5.5 to 8.5 d.p.c.), 3-D reconstruction of the gravid uterus in both mesh and solid overlay format enabled visual representation of the developing pregnancies within each uterine horn. As genetically engineered mice continue to be used to characterize female reproductive phenotypes derived from uterine dysfunction, this method offers a new approach to detect, quantify, and characterize early implantation events in vivo. This novel use of 3-D HFUS imaging demonstrates the ability to successfully detect, visualize, and characterize embryo-implantation sites during early murine pregnancy in a non-invasive manner. The technology offers a significant improvement over current methods, which rely on the interruption of pregnancies for gross tissue and histopathologic characterization. Here we use a video and text format to describe how to successfully perform ultrasounds of early murine pregnancy to generate reliable and reproducible data with reconstruction of the uterine form in mesh and solid 3-D images.

Advanced maternal age and adverse pregnancy outcomes: A systematic review and meta-analysis

BACKGROUND

Advanced maternal age (AMA; ≥35 years) is an increasing trend and is reported to be associated with various pregnancy complications.

OBJECTIVE

To determine the risk of stillbirth and other adverse pregnancy outcomes in women of AMA.

SEARCH STRATEGY

Embase, Medline (Ovid), Cochrane Database of Systematic Reviews, ClinicalTrials.gov, LILACS and conference proceedings were searched from ≥2000.

SELECTION CRITERIA

Cohort and case-control studies reporting data on one or more co-primary outcomes (stillbirth or fetal growth restriction (FGR)) and/or secondary outcomes in mothers ≥35 years and <35 years.

DATA COLLECTION AND ANALYSIS

The effect of age on pregnancy outcome was investigated by random effects meta-analysis and meta-regression. Stillbirth rates were correlated to rates of maternal diabetes, obesity, hypertension and use of assisted reproductive therapies (ART).

MAIN RESULTS

Out of 1940 identified titles; 63 cohort studies and 12 case-control studies were included in the meta-analysis. AMA increased the risk of stillbirth (OR 1.75, 95%CI 1.62 to 1.89) with a population attributable risk of 4.7%. Similar trends were seen for risks of FGR, neonatal death, NICU unit admission restriction and GDM. The relationship between AMA and stillbirth was not related to maternal morbidity or ART.

CONCLUSIONS

Stillbirth risk increases with increasing maternal age. This is not wholly explained by maternal co-morbidities and use of ART. We propose that placental dysfunction may mediate adverse pregnancy outcome in AMA. Further prospective studies are needed to directly test this hypothesis.

Multidisciplinary consensus on screening for, diagnosis and management of fetal growth restriction in the Netherlands

BACKGROUND

Screening for, diagnosis and management of intrauterine growth restriction (IUGR) is often performed in multidisciplinary collaboration. However, variation in screening methods, diagnosis and management of IUGR may lead to confusion. In the Netherlands two monodisciplinary guidelines on IUGR do not fully align. To facilitate effective collaboration between different professionals in perinatal care, we undertook a Delphi study with uniform recommendations as our primary result, focusing on issues that are not aligned or for which specifications are lacking in the current guidelines.

METHODS

We conducted a Delphi study in three rounds. A purposively sampled selection of 56 panellists participated: 27 representing midwife-led care and 29 obstetrician-led care. Consensus was defined as agreement between the professional groups on the same answer and among at least 70% of the panellists within groups.

RESULTS

Per round 51 or 52 (91% - 93%) panellists responded. This has led to consensus on 27 issues, leading to four consensus based recommendations on screening for IUGR in midwife-led care and eight consensus based recommendations on diagnosis and eight on management in obstetrician-led care. The multidisciplinary project group decided on four additional recommendations as no consensus was reached by the panel. No recommendations could be made about induction of labour versus expectant monitoring, nor about the choice for a primary caesarean section.

CONCLUSIONS

We reached consensus on recommendations for care for IUGR within a multidisciplinary panel. These will be implemented in a study on the effectiveness and cost-effectiveness of routine third trimester ultrasound for monitoring fetal growth. Research is needed to evaluate the effects of implementation of these recommendations on perinatal outcomes.

TRIAL REGISTRATION

NTR4367 .

Assessment of M2/ANXA5 haplotype as a risk factor in couples with placenta-mediated pregnancy complications

PURPOSE

The aim of this study was to confirm the associated M2/ANXA5 carrier risk in women with placenta-mediated pregnancy complications (PMPC) and to test their male partners for such association. Further analysis evaluated the influence of maternal vs. paternal M2 alleles on miscarriage.

METHODS

Two hundred eighty-eight couples with preeclampsia (PE), intrauterine growth restriction (IUGR), or premature birth (PB) were recruited (n = 96 of each phenotype). The prevalence of the M2 haplotype was compared to two control cohorts. They included a group of women with a history of normal pregnancy without gestational pathology (Munich controls, n = 94) and a random population sample (PopGen controls, n = 533).

RESULTS

Significant association of M2 haplotype and pregnancy complications was confirmed for women and for couples, where prevalence was elevated from 15.4 to 23.8% (p < 0.001). Post hoc analyses demonstrated an association for IUGR and PB individually. A strong link between previous miscarriages and M2 carrier status was identified which may explain the predisposition to placental pregnancy complication. M2/ANXA5 appears to be a risk factor for adverse pregnancy outcomes related, but not limited to miscarriages, with similar prevalence in women and their male partners.

CONCLUSION

These findings support the proposed physiological function of ANXA5 as an embryonic anticoagulant that appears deficient in contiguous specter of thrombophilia-related pregnancy complications culminating more frequently in miscarriage in a maternal M2 carrier background.

Defining fetal growth restriction: abdominal circumference as an alternative criterion

PURPOSE

The purpose of this study is to determine if using abdominal circumference percentile (AC) to define fetal growth restriction (FGR) improves ultrasound at ≥36 weeks as a screening test for small for gestational age (SGA).

MATERIALS AND METHODS

All non-anomalous singletons undergoing ultrasound at a single center at ≥36 weeks during 12/2008-5/2014 were included. FGR was defined as (estimated fetal weight) estimated fetal weight (EFW) and/or abdominal circumference (AC) < 10 for gestational age (GA). The primary outcome was SGA (birthweight ≤10th percentile for GA). Data were stratified by maternal race/ethnicity and BMI. Sensitivity, specificity, false-positive rate (FPR), positive- and negative-predictive values (positive-predictive value (PPV), negative-predictive value (NPV)), and areas under the receiver-operating characteristic (ROC) curve (AUC were calculated.

RESULTS

There were 1594 ultrasounds. Median (IQR) ultrasound GA was 37.3 (36.6-38.0), days to delivery 10.6 (5.0-18.4), and delivery GA 39.29 (38.6-39.9). EFW <10 had the following characteristics: sensitivity 50.6%, FPR 2.0%, PPV 83.8%, and AUC 0.743. Using AC <10, these were 64.0, 2.9, 81.3, and 0.806, respectively. Using AC or EFW <10, these were 67.5, 3.3, 80.3, and 0.821, respectively; this criterion has the largest AUC (p < .008). This finding persisted when stratified by maternal race/ethnicity and BMI.

CONCLUSIONS

AC <10 is more sensitive and has a similar PPV compared with EFW <10 for SGA. Using AC <10 or EFW <10 has the best balance of sensitivity and specificity as a screening test and has a low FPR. AC may be a reasonable alternative criterion to EFW for FGR diagnosis.

Detection and assessment of brain injury in the growth-restricted fetus and neonate

Fetal growth restriction (FGR) is a common complication of pregnancy and, in severe cases, is associated with elevated rates of perinatal mortality, neonatal morbidity, and poor neurodevelopmental outcomes. The leading cause of FGR is placental insufficiency, with the placenta failing to adequately meet the increasing oxygen and nutritional needs of the growing fetus with advancing gestation. The resultant chronic fetal hypoxia induces a decrease in fetal growth, and a redistribution of blood flow preferentially to the brain. However, this adaptation does not ensure normal brain development. Early detection of brain injury in FGR, allowing for the prediction of short- and long-term neurodevelopmental consequences, remains a significant challenge. Furthermore, in FGR infants the detection and diagnosis of neuropathology is complicated by preterm birth, the etiological heterogeneity of FGR, timing of onset of growth restriction, its severity, and coexisting complications. In this review, we examine existing and emerging diagnostic tools from human and preclinical studies for the detection and assessment of brain injury in FGR fetuses and neonates. Increased detection rates, and early detection of brain injury associated with FGR, will offer opportunities for developing and assessing interventions to improve long-term outcomes.

Variation in the definition of intrauterine growth restriction in routine antenatal care: a physician survey among gynecologists in Northwest Germany

OBJECTIVE

To assess how intrauterine growth restriction (IUGR) is defined by gynecologists in routine practice.

MATERIALS AND METHODS

We surveyed primary care gynecologists in Bremen and Lower Saxony, Northwest Germany, between January and July 2014. Descriptive statistics were used to analyze the data; consensus was considered as 90% agreement among the respondents. Multiple logistic regression models were performed for the associations between respondents' background characteristics and choice of the small for gestational age (SGA) cutoff values.

RESULTS

Overall, 185 primary care gynecologists participated in the survey. Consensus was only observed in two items: (1) an accurate determination of gestational age (91%) and (2) repeated measurement of the abdominal circumference (91%). Umbilical artery Doppler (76%) and repeated ultrasonography (76%) were the most frequently used methods to confirm suspected IUGR diagnoses, but different responses prevailed. Notably, only 46% of the respondents opted for the 10th percentile of estimated fetal weight as a cutoff for SGA classification, which is the internationally recommended value.

CONCLUSIONS

The results of this survey indicate considerable practice variation regarding detection and management of IUGR pregnancies. There is a need for better agreement in terminology and definition of core aspects of IUGR in antenatal care.

Consensus definition of fetal growth restriction: a Delphi procedure

OBJECTIVE

To determine, by expert consensus, a definition for early and late fetal growth restriction (FGR) through a Delphi procedure.

METHOD

A Delphi survey was conducted among an international panel of experts on FGR. Panel members were provided with 18 literature-based parameters for defining FGR and were asked to rate the importance of these parameters for the diagnosis of both early and late FGR on a 5-point Likert scale. Parameters were described as solitary parameters (parameters that are sufficient to diagnose FGR, even if all other parameters are normal) and contributory parameters (parameters that require other abnormal parameter(s) to be present for the diagnosis of FGR). Consensus was sought to determine the cut-off values for accepted parameters.

RESULTS

A total of 106 experts were approached, of whom 56 agreed to participate and entered the first round, and 45 (80%) completed all four rounds. For early FGR (< 32 weeks), three solitary parameters (abdominal circumference (AC) < 3(rd) centile, estimated fetal weight (EFW) < 3(rd) centile and absent end-diastolic flow in the umbilical artery (UA)) and four contributory parameters (AC or EFW < 10(th) centile combined with a pulsatility index (PI) > 95(th) centile in either the UA or uterine artery) were agreed upon. For late FGR (≥ 32 weeks), two solitary parameters (AC or EFW < 3(rd) centile) and four contributory parameters (EFW or AC < 10(th) centile, AC or EFW crossing centiles by > two quartiles on growth charts and cerebroplacental ratio < 5(th) centile or UA-PI > 95(th) centile) were defined.

CONCLUSION

Consensus-based definitions for early and late FGR, as well as cut-off values for parameters involved, were agreed upon by a panel of experts. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Early functional and morphological brain disturbances in late-onset intrauterine growth restriction

AIMS

To determine whether the brain disturbances develop in late-onset intrauterine growth restriction (IUGR) before blood flow redistribution towards the fetal brain (detected by Doppler measurements in the middle cerebral artery and umbilical artery). Further, to evaluate predictive values of Doppler arterial indices and umbilical cord blood gases and pH for early functional and/or morphological brain disturbances in late-onset IUGR.

STUDY DESIGN

This cohort study included 60 singleton term pregnancies with placental insufficiency caused late-onset IUGR (IUGR occurring after 34 gestational weeks). Umbilical artery resistance index (URI), middle cerebral artery resistance index (CRI), and cerebroumbilical (C/U) ratio (CRI/URI) were monitored once weekly. Umbilical blood cord samples (arterial and venous) were collected for the analysis of pO2, pCO2 and pH. Morphological neurological outcome was evaluated by cranial ultrasound (cUS), whereas functional neurological outcome by Amiel-Tison Neurological Assessment at Term (ATNAT).

RESULTS

50 fetuses had C/U ratio>1, and 10 had C/U ratio≤1; among these 10 fetuses, 9 had abnormal neonatal cUS findings and all 10 had non-optimal ATNAT. However, the total number of abnormal neurological findings was much higher. 32 neonates had abnormal cUS (53.37%), and 42 (70.00%) had non-optimal ATNAT. Furthermore, Doppler indices had higher predictive validity for early brain disturbances than umbilical cord blood gases and pH. C/U ratio had the highest predictive validity with threshold for adverse neurological outcome at value 1.13 (ROC analysis), i.e., 1.18 (party machine learning algorithm).

CONCLUSION

Adverse neurological outcome at average values of C/U ratios>1 confirmed that early functional and/or structural brain disturbances in late-onset IUGR develop even before activation of fetal cardiovascular compensatory mechanisms, i.e., before Doppler signs of blood flow redistribution between the fetal brain and the placenta.

DNA Methylation and Expression Patterns of Selected Genes in First-Trimester Placental Tissue from Pregnancies with Small-for-Gestational-Age Infants at Birth

Variations in DNA methylation levels in the placenta are thought to influence gene expression and are associated with complications of pregnancy, like fetal growth restriction (FGR). The most important cause for FGR is placental dysfunction. Here, we examined whether changes in DNA methylation, followed by gene expression changes, are mechanistically involved in the etiology of FGR. In this retrospective case-control study, we examined the association between small-for-gestational-age (SGA) children and both DNA methylation and gene expression levels of the genes WNT2, IGF2/H19, SERPINA3, HERVWE1, and PPARG in first-trimester placental tissue. We also examined the repetitive element LINE-1. These candidate genes have been reported in the literature to be associated with SGA. We used first-trimester placental tissue from chorionic villus biopsies. A total of 35 SGA children (with a birth weight below the 10th percentile) were matched to 70 controls based on their gestational age. DNA methylation levels were analyzed by pyrosequencing and mRNA levels were analyzed by real-time PCR. None of the average DNA methylation levels, measured for each gene, showed a significant difference between SGA placental tissue compared to control tissue. However, hypermethylation of WNT2 was detected on two CpG positions in SGA. This was not associated with changes in gene expression. Apart from two CpG positions of the WNT2 gene, in early placenta samples, no evident changes in DNA methylation or expression were found. This indicates that the already reported changes in term placenta are not present in the early placenta, and therefore must arise after the first trimester.

Third-Trimester Fetal Biometry and Neonatal Outcomes in Term and Preterm Deliveries

OBJECTIVES

To determine whether specific biometric thresholds for head circumference, abdominal circumference, femur length, and estimated fetal weight can identify neonates at risk for adverse outcomes.

METHODS

We conducted a retrospective analysis of women with sonographic biometry after 26 weeks' gestational age (GA) followed by delivery of term and preterm neonates from 2007 through 2011. The head circumference, abdominal circumference, femur length, and estimated fetal weight were obtained. Sonographic data were merged with birth certificate and neonatal data. Biometry and estimated fetal weight were divided into percentile thresholds: 10th and above (reference), below 10th, below 5th, and below 3rd. Neonatal outcomes included neonatal intensive care unit admission, 5-minute Apgar score less than 7, and a composite of any morbidity/mortality (hypoxic-ischemic encephalopathy, periventricular leukomalacia, necrotizing enterocolitis, sepsis, renal failure, or death). Logistic regression yielded odds ratios and 95% confidence intervals for biometry and outcome, then adjusted for GA at delivery.

RESULTS

A total of 2237 patients delivered at term, and 455 delivered before term. Neonatal intensive care unit admission was not associated with any biometric threshold in the term and preterm groups. Five-minute Apgar score less than 7 was associated with head circumference below 10th, abdominal circumference below 3rd, and estimated fetal weight below 5th percentiles in the term group and head circumference below 10th, abdominal circumference below 10th, and femur length below 10th percentiles in the preterm group (P < .05). Composite morbidity/mortality was associated with abdominal circumference below 5th, femur length below 10th, and femur length below 3rd percentiles in the term group and head circumference below 5th, abdominal circumference below 10th, and femur length below 5th percentiles in the preterm group (P< .05). Adjustment for GA did not affect outcomes for term deliveries but did affect nearly all outcomes for preterm deliveries.

CONCLUSIONS

Irrespective of GA, no one biometric threshold can accurately predict adverse neonatal outcomes.

Effect of late-onset fetal growth restriction on organization of behavioral state in infants

BACKGROUND

The aim of this study was to analyze whether late-onset fetal growth restriction (FGR) alters regulatory capability in infants, and whether this can be detected using both the neonatal behavior assessment scale (NBAS) and brainstem auditory-evoked potentials (BAEP).

METHODS

The diagnosis of FGR was made on Doppler examination in the third trimester of pregnancy. NBAS and BAEP measurement were performed at 1 month of corrected postnatal age.

RESULTS

The group with late-onset FGR was integrated with 17 infants and the control group consisted of 14 subjects. The NBAS range of state score, which reflects organization of behavioral state, was low in infants with late-onset FGR. No differences were found in BAEP between groups. No association between NBAS and BAEP was detected.

CONCLUSION

Late-onset FGR has a deleterious effect on NBAS range of state, but possibly does not alter BAEP response. It is proposed that regulatory capabilities in the neonatal period play a primary role in subtle cognitive difficulties in infants with late-onset FGR in the long term.

Maternal Nutrient Restriction Alters Ca2+ Handling Properties and Contractile Function of Isolated Left Ventricle Bundles in Male But Not Female Juvenile Rats

Intrauterine growth restriction (IUGR), defined as a birth weight below the 10th centile, may be caused by maternal undernutrition, with evidence that IUGR offspring have an increased risk of cardiovascular disease (CVD) in adulthood. Calcium ions (Ca²⁺) are an integral messenger for several steps associated with excitation-contraction coupling (ECC); the cascade of events from the initiation of an action potential at the surface membrane, to contraction of the cardiomyocyte. Any changes in Ca²⁺ storage and release from the sarcoplasmic reticulum (SR), or sensitivity of the contractile apparatus to Ca²⁺ may underlie the mechanism linking IUGR to an increased risk of CVD. This study aimed to explore the effects of maternal nutrient restriction on cardiac function, including Ca²⁺ handling by the SR and force development by the contractile apparatus. Juvenile Long Evans hooded rats born to Control (C) and nutrient restricted (NR) dams were anaesthetized for collection of the heart at 10–12 weeks of age. Left ventricular bundles from male NR offspring displayed increased maximum Ca²⁺-activated force, and decreased protein content of troponin I (cTnI) compared to C males. Furthermore, male NR offspring showed a reduction in rate of rise of the caffeine-induced Ca²⁺ force response and a decrease in the protein content of ryanodine receptor (RYR2). These physiological and biochemical findings observed in males were not evident in female offspring. These findings illustrate a sex-specific effect of maternal NR on cardiac development, and also highlight a possible mechanism for the development of hypertension and hypertrophy in male NR offspring.

[Pilot study on stress and resilience in families with premature newborns]

INTRODUCTION

Prematurity is associated with severe clinical conditions, long hospital stays, and uncertainty about patient outcomes. These circumstances lead to a stressful situation that may affect family functioning. The aim of this study was to study risk and protection factors affecting family functioning in preterm as compared to healthy term infants.

POPULATION AND METHODS

Preterm infants with and without pathological conditions (n=40) were recruited at 24 months post-conception age, together with a control group of healthy term newborn infants (n=31). Parents or usual caregivers responded to the Inventory of Family Protection Factors and Parental Stress scales. The results were compared using the Student t test, unidirectional analysis of variance and the Tukey test.

RESULTS

Parents of the control group attained higher scores than those of the preterm group for all the items studied; however, parents of preterm infants with pathological conditions perceived significantly less family resilience and more stress related to the upbringing of their child.

CONCLUSIONS

Prematurity itself is a risk factor for family dysfunction because it causes an elevated degree of parental stress and difficulties in the development of protection factors such as resilience.

Maternal thyrotropin is independently related to small for gestational age neonates at term

OBJECTIVE

Small for gestational age (SGA) newborns constitute still a major cause of perinatal morbidity and mortality. Overt thyroid disease is a known cause of preterm birth and low birthweight but in its untreated condition it is rare today. In this study, we investigated the possible relation between maternal thyroid function assessed in euthyroid women at each trimester and the incidence of term born SGA neonates.

DESIGN

A prospective cohort study was performed.

PATIENTS

Thyroid function was assessed at 12, 24 and 36 weeks gestation in 1051 healthy Caucasian women who delivered at ≥ 37 weeks gestation.

MEASUREMENTS

One-way anova was used to compare mean TSH and FT4 levels between women with SGA neonates and controls. Multiple logistic regression analysis was performed to adjust for known risk factors of SGA.

RESULTS

Seventy (6·7%) SGA neonates were identified and they were significantly more often born to women with a TSH ≥ 97·5th at first and third trimester. Multiple logistic regression analysis showed that smoking (OR: 4·4, 95% CI: 2·49-7·64), pre-eclampsia (OR: 2·8, 95% CI: 1·19-6·78) and TSH ≥ 97·5th percentile (OR 3·3, 95% CI 1·39-7·53) were significantly related to SGA. Maternal FT4 levels and TPO-Ab status were not associated with SGA offspring.

CONCLUSIONS

Our data show that TSH levels in the upper range of the reference interval at different trimesters (3·0-3·29 mIU/l) are independently related to an increased risk of delivering SGA neonates at term.

Intrauterine growth restriction and hypospadias: is there a connection?

Hypospadias is one of the most common congenital malformations of the genitourinary tract in males. It is an incomplete fusion of urethral folds early in fetal development and may be associated with other malformations of the genital tract. The etiology is poorly understood and may be hormonal, genetic, or environmental, but most often is idiopathic or multifactorial. Among many possible risk factors identified, of particular importance is low birth weight, which is defined in various ways in the literature. No mechanism has been identified for the association of low birth weight and hypospadias, but some authors propose placental insufficiency as a common inciting factor. Currently, there is no standardized approach for evaluating children with hypospadias in the setting of intrauterine growth restriction. We reviewed the available published literature on the association of hypospadias and growth restriction to determine whether it should be considered a separate entity within the category of disorders of sexual differentiation.

Gestational age and fetal growth assessment among obstetricians

OBJECTIVE

We aimed to characterize gestational age assessment and fetal growth evaluation among obstetricians.

METHODS

Observational, cross-sectional study. We applied a questionnaire to obstetrics specialists and residents, during a national congress on obstetrics.

RESULTS

Almost all 179 respondents correct gestational age in the first trimester by ultrasound, but 63% only if there is a difference of 2-9 days. Ultrasound at 11-13 weeks was considered more accurate than at 8-10 weeks by 81%, with a higher proportion of specialists choosing correctly the last answer (p = 0.05). One-third of the respondents did not correctly point the error associated with the ultrasound estimation of fetal weight (EFW). Of the 88% who use a growth table, only 32% were able to identify it by publication/author. Ninety-eight percent identify fetal growth restriction risk (FGR) with centiles (10th in 76%) and 73% of doctors diagnose FGR without other pathological findings (10th in 49%). 44% finds that a low EFW centile maintenance (4th to 3rd) is more worrisome than the crossing of two quartiles (75th to 24th).

CONCLUSIONS

The role of ultrasound in gestational age assessment and use of EFW use for FGR classification was disparate among participants. EFW and respective centiles may be over relied upon.

Defining the residual risk of adverse perinatal outcome in growth-restricted fetuses with normal umbilical artery blood flow

OBJECTIVE

We sought to determine the cause of adverse perinatal outcome in fetal growth restriction (FGR) where umbilical artery (UA) Doppler was normal, as identified from the Prospective Observational Trial to Optimize Pediatric Health (PORTO). We compared cases of adverse outcome where UA Doppler was normal and abnormal.

STUDY DESIGN

The PORTO study was a national multicenter study of >1100 ultrasound-dated singleton pregnancies with an estimated fetal weight <10th centile. Each pregnancy underwent intensive ultrasound, including multivessel Doppler. UA Doppler was considered abnormal when the pulsatility index was >95th centile or end-diastolic flow was absent/reversed. Adverse perinatal outcome was defined as a composite of intraventricular hemorrhage, periventricular leukomalacia, hypoxic ischemic encephalopathy, necrotizing enterocolitis, bronchopulmonary dysplasia, sepsis, or death.

RESULTS

In all, 57 (5.0%) of the 1116 fetuses had an adverse perinatal outcome. Nine (1.3%) of 698 fetuses with normal UA Doppler had an adverse outcome, compared with 48 (11.5%) of 418 with abnormal UA Doppler (P < .0001). There were 2 perinatal deaths in the normal group and 6 in the abnormal group (P = .01). The perinatal deaths in the normal group were 1 case of pulmonary hypoplasia after prolonged preterm rupture of the membranes from 12 weeks' gestation and a case of placental abruption. Gestation at delivery was 33 ± 3 vs 31 ± 4 weeks (P = .05) and mean birthweight was 1830 ± 737 vs 1146 ± 508 g (P = .001) in the respective groups. Neonatal sepsis was the commonest adverse outcome in both groups: 0.1% and 0.4%, respectively (P = .01).

CONCLUSION

Adverse perinatal outcome is uncommon in FGR with normal UA Doppler. The cases we identified were associated with heterogenous pathologies. FGR with normal UA blood flow is a largely benign condition.