The World Health Organization fetal growth charts: concept, findings, interpretation, and application

Prediction of adverse perinatal outcome by fetal biometry: comparison of customized and population-based standards

OBJECTIVE

To compare the predictive performance of estimated fetal weight (EFW) percentiles, according to eight growth standards, to detect fetuses at risk for adverse perinatal outcome.

METHODS

This was a retrospective cohort study of 3437 African-American women. Population-based (Hadlock, INTERGROWTH-21^st , World Health Organization (WHO), Fetal Medicine Foundation (FMF)), ethnicity-specific (Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)), customized (Gestation-Related Optimal Weight (GROW)) and African-American customized (Perinatology Research Branch (PRB)/NICHD) growth standards were used to calculate EFW percentiles from the last available scan prior to delivery. Prediction performance indices and relative risk (RR) were calculated for EFW < 10^th and > 90^th percentiles, according to each standard, for individual and composite adverse perinatal outcomes. Sensitivity at a fixed (10%) false-positive rate (FPR) and partial (FPR < 10%) and full areas under the receiver-operating-characteristics curves (AUC) were compared between the standards.

RESULTS

Ten percent (341/3437) of neonates were classified as small-for-gestational age (SGA) at birth, and of these 16.4% (56/341) had at least one adverse perinatal outcome. SGA neonates had a 1.5-fold increased risk of any adverse perinatal outcome (P < 0.05). The screen-positive rate of EFW < 10^th percentile varied from 6.8% (NICHD) to 24.4% (FMF). EFW < 10^th percentile, according to all standards, was associated with an increased risk for each of the adverse perinatal outcomes considered (P < 0.05 for all). The highest RRs associated with EFW < 10^th percentile for each adverse outcome were 5.1 (95% CI, 2.1-12.3) for perinatal mortality (WHO); 5.0 (95% CI, 3.2-7.8) for perinatal hypoglycemia (NICHD); 3.4 (95% CI, 2.4-4.7) for mechanical ventilation (NICHD); 2.9 (95% CI, 1.8-4.6) for 5-min Apgar score < 7 (GROW); 2.7 (95% CI, 2.0-3.6) for neonatal intensive care unit (NICU) admission (NICHD); and 2.5 (95% CI, 1.9-3.1) for composite adverse perinatal outcome (NICHD). Although the RR CIs overlapped among all standards for each individual outcome, the RR of composite adverse perinatal outcome in pregnancies with EFW < 10^th percentile was higher according to the NICHD (2.46; 95% CI, 1.9-3.1) than the FMF (1.47; 95% CI, 1.2-1.8) standard. The sensitivity for composite adverse perinatal outcome varied substantially between standards, ranging from 15% for NICHD to 32% for FMF, due mostly to differences in FPR; this variation subsided when the FPR was set to the same value (10%). Analysis of AUC revealed significantly better performance for the prediction of perinatal mortality by the PRB/NICHD standard (AUC = 0.70) compared with the Hadlock (AUC = 0.66) and FMF (AUC = 0.64) standards. Evaluation of partial AUC (FPR < 10%) demonstrated that the INTERGROWTH-21^st standard performed better than the Hadlock standard for the prediction of NICU admission and mechanical ventilation (P < 0.05 for both). Although fetuses with EFW > 90^th percentile were also at risk for any adverse perinatal outcome according to the INTERGROWTH-21^st (RR = 1.4; 95% CI, 1.0-1.9) and Hadlock (RR = 1.7; 95% CI, 1.1-2.6) standards, many times fewer cases (2-5-fold lower sensitivity) were detected by using EFW > 90^th percentile, rather than EFW < 10^th percentile, in screening by these standards.

CONCLUSIONS

Fetuses with EFW < 10^th percentile or EFW > 90^th percentile were at increased risk of adverse perinatal outcomes according to all or some of the eight growth standards, respectively. The RR of a composite adverse perinatal outcome in pregnancies with EFW < 10^th percentile was higher for the most-stringent (NICHD) compared with the least-stringent (FMF) standard. The results of the complementary analysis of AUC suggest slightly improved detection of adverse perinatal outcome by more recent population-based (INTERGROWTH-21^st ) and customized (PRB/NICHD) standards compared with the Hadlock and FMF standards. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.

Postnatal development of skeletal muscle in pigs with intrauterine growth restriction: morphofunctional phenotype and molecular mechanisms

Intrauterine growth restriction (IUGR) is a serious condition which impairs the achievement of the fetus' full growth potential and occurs in a natural and severe manner in pigs as a result of placental insufficiency. Reduced skeletal muscle mass in the fetus with IUGR persists into adulthood and may contribute to increased metabolic disease risk. To investigate skeletal muscle postnatal development, histomorphometrical patterns of the semitendinosus muscle, myosin heavy chain (MyHC; embryonic I, IIA, IIB and IIX isoforms) fiber composition and the relative expression of genes related to myogenesis, adipogenesis and growth during three specific periods: postnatal myogenesis (newborn to 100 days old), hypertrophy (100-150 days old), and postnatal development (newborn to 150 days old) were evaluated in female pigs with IUGR and normal birth weight (NW) female littermates. NW females presented higher body weights compared to their IUGR counterparts at all ages evaluated (P < 0.05). Moreover, growth restriction in utero affected the semitendinosus muscle weight, muscle fiber diameter, and muscle cross-sectional area, which were smaller in IUGR pigs at birth (P < 0.05). Notwithstanding the effects on muscle morphology, IUGR also affected muscle fiber composition, as the percentage of MyHC-I myofibers was higher at birth (P < 0.05), and, in 150-day-old gilts, a lower percentage of MyHC-IIX isoform (P < 0.05) and the presence of embryonic MyHC isoform were also observed. Regarding the pattern of gene expression in both the postnatal myogenesis and postnatal development periods, IUGR led to the downregulation of myogenic factors, which delayed skeletal muscle myogenesis (PAX7, MYOD, MYOG, MYF5 and DES). Altogether, growth restriction in utero affects muscle fiber number and size at birth and muscle fiber composition through the downregulation of myogenic factors, which determines the individual´s postnatal growth rate. This fact, associated with delayed myofiber development in growth-restricted animals, may affect meat quality characteristics in animal production. Hence, knowledge of the morphofunctional phenotype of the skeletal muscle throughout postnatal development in individuals with IUGR, and the mechanism that governs it, may provide a better understanding of the mechanisms that limit postnatal muscle growth, and help the establishment of potential strategies to improve muscle development and prevent the onset of later-life metabolic diseases.

Intrauterine growth patterns in rural Ethiopia compared with WHO and INTERGROWTH-21st growth standards: A community-based longitudinal study

INTRODUCTION

Children's well-being is highly influenced by their fetal growth. Adequate intrauterine growth (IUG) is a basic feature of a healthy pregnancy. The aim of our study was to assess IUG patterns in a rural and drought-affected population in the Rift Valley area of the Adami Tullu district in Oromia, Ethiopia.

METHODS

We conducted a longitudinal, community-based study of IUG patterns utilizing serial ultrasound measurements. Data were collected for 17 months, from July 2016 to November 2017. We included 675 singleton foetuses ≤ 24 weeks old, based on ultrasound-derived estimates of gestational age, and followed them until delivery. We obtained head circumference, biparietal diameter, abdominal circumference, femur length, and estimated fetal weight at 26, 30, and 36 weeks. Fetal weight was estimated using the Hadlock algorithm, and the 5th, 10th, 25th, 50th, 75th, 90th, and 95th centiles were developed from this model. We compared the biometric measurements and fetal weight data from our study to the World Health Organization (WHO) and INTERGROWTH-21st fetal growth reference standards.

RESULTS

Distribution of the biometric measurements and estimated fetal weights in our study were similar to those for the WHO and INTERGROWTH-21st references. Most measurements were between -2 and +2 of the reference z-scores. Based on the smoothed percentiles, the 5th, 50th, and 95th percentiles of our study had similar distribution patterns to the WHO chart, and the 50th percentile had a similar pattern to the INTERGROWTH-21st chart.

CONCLUSIONS

Our study determined fetal growth patterns in a drought-affected rural community of Ethiopia using common ultrasound biometric measurements. We found similar IUG patterns to those indicated in the WHO and INTERGROWTH-21st fetal growth reference standards.

Attenuation of sympathoadrenal function during delivery in the fetus of a diabetic mother

Objective: We compared the association between cord arterial catecholamine levels and fetal oxygenation in newborns of mothers with diabetes mellitus to those of nondiabetic pregnancies.Methods: Cord blood obtained at delivery in 25 term appropriate-for-gestational age newborns of women with diabetes and 27 nondiabetic controls were assayed for norepinephrine, epinephrine, insulin, glucose, and blood gases.Results: There was no statistical difference in parity, birth weight, gestational age, delivery mode, use of epidural analgesia, or frequency of low 1-min Apgar scores between the groups. The pO₂ and frequency of cord arterial pH < 7.20 were also similar. Diabetic pregnancies had somewhat higher fetal glucose and substantially higher insulin levels than controls. Regression analysis using cord arterial pH to reflect oxygenation revealed significant inverse relationships between cord artery pH and ln norepinephrine (Prob > F = .001) and ln epinephrine (Prob > F = .019) in controls. In newborns of women with diabetes, however, neither relationship was significant.Conclusion: The expected surge in catecholamines associated with diminished oxygenation was attenuated in fetuses of diabetic mothers. This suggests the possibility that fetal exposure to hyperglycemia or other metabolic derangements in pregnant diabetics might compromise the fetal ability to adapt to changes in oxygenation, and might thereby contribute to the risk of fetal death.

Risk of intellectual disability in children born appropriate-for-gestational-age at term or post-term: impact of birth weight for gestational age and gestational age

Children born small for gestational age have a higher risk of intellectual disability. We investigated associations of birth weight for gestational age percentile and gestational age with risk of intellectual disability in appropriate-for-gestational-age (AGA) children. We included 828,948 non-malformed term or post-term AGA singleton children (including 429,379 full siblings) born between 1998 and 2009 based on data from the Swedish Medical Birth Register. Diagnosis of intellectual disability after 3 years of age was identified through the Patient Register. Using Cox regression models, we calculated hazard ratios (HRs) with 95% confidence intervals (CIs) of intellectual disability among children with different birth weight percentiles and gestational age in the whole population and in a subpopulation of full siblings. A total of 1688 children were diagnosed with intellectual disability during follow-up. HRs (95% CIs) of intellectual disability for the low birth weight percentile groups (10th–24th and 25th–39th percentiles, respectively) versus the reference group (40th–59th percentiles) were 1.43 (1.22–1.67) and 1.28 (1.10–1.50) in population analysis and 1.52 (1.00–2.31) and 1.44 (1.00–2.09) in sibling comparison analysis. The increased risk for low birth weight percentiles in population analysis was stable irrespective of gestational age. A weak U-shaped association between gestational age and intellectual disability was observed in population analysis, although not in sibling comparison analysis. These findings suggest that among AGA children born at term or post-term, lower birth weight percentiles within the normal range are associated with increased risk of intellectual disability, regardless of gestational age.

Stratified analysis of the correlation between gestational weight gain and birth weight for gestational age: a retrospective single-center cohort study in Japan

BACKGROUND

Japan has an exceptionally high proportion of low-weight births and underweight women. It has been suggested that an appropriate increase in gestational weight gain (GWG) for underweight women will help to prevent low birth weight. The current strategy aims to raise the desired value of GWG equally for all pregnant women within the underweight category. However, it remains elusive whether or not the relationship between GWG and birth weight for gestational age (BW/GA) are uniformly equivalent for all the women.

METHODS

We performed a retrospective cohort analysis of women who delivered their newborns at Tokyo Medical and Dental University Hospital from 2013 to 2017. First, in order to examine the direct effect of an increase or decrease in GWG on BW/GA, we analyzed the correlation between inter-pregnancy differences in GWG and BW/GA using a sub-cohort of women who experienced two deliveries during the study period (n = 75). Second, we dichotomized the main cohort (n = 1114) according to BW/GA to verify our hypothesis that the correlation between GWG and BW/GA differs depending on the size of the newborn.

RESULTS

The inter-pregnancy difference in BW/GA was not correlated with that of GWG. However, the correlation between BW/GA of siblings was high (r = 0.63, p = 1.9 × 10^- 9). The correlation between GWG and BW/GA in women who delivered larger-sized newborns was higher (r = 0.17, p = 4.1 × 10^- 5) than that in women who delivered smaller-sized newborns (r = 0.099, p = 1.9 × 10^- 2). This disparity did not change after adjustment for pre-pregnancy BMI. The mean birth weight in the dichotomized groups corresponded to percentile 52.0 and 13.4 of the international newborn size assessed by INTERGROWTH-21st standards.

CONCLUSIONS

In our study, GWG was positively correlated with BW/GA for heavier neonates whose birth weights were similar to the average neonatal weight according to world standards. However, caution might be required for low-birth-weight neonates because increased GWG does not always result in increased birth weight.

Comparison of the INTERGROWTH-21st standard and a new reference for head circumference at birth among newborns in Southern China

BACKGROUND

Previous studies proposed that there were racial or ethnic disparities in fetal growth, challenging the use of international standards in specific populations. This study was to evaluate the validity of applying the INTERGROWTH-21st standard to a Chinese population for identifying abnormal head circumference (HC), in comparison with a newly generated local reference.

METHODS

There were 24,257 singletons delivered by low-risk mothers in four perinatal health-care centers in Southern China. New HC reference was constructed and comparison in distribution of HC categories was performed between the INTERGROWTH-21st standard and new reference after applying these two tools in study population. Logistic regression was used to examine the association between abnormal HC and adverse neonatal outcomes.

RESULTS

There were 4.40% of the newborns identified with microcephaly (HC > 2 standard deviation below the mean) using the INTERGROWTH-21st standard, comparing to the proportion of 2.83% using new reference. The newborns identified with microcephaly only by the INTERGROWTH-21st standard were not at a higher risk of adverse neonatal outcome, compared with those identified as non-microcephaly by both tools (OR 0.73, 95% CI 0.47-1.13).

CONCLUSION

The new HC reference may be more appropriate for newborn assessment in Chinese populations than the INTERGROWTH-21st standard.

New reference values for biometrical measurements and sonographic estimated fetal weight in twin gestations and comparison to previous normograms

Objective To construct new reference values for biometrical measurements and sonographic estimated fetal weight (sEFW) in twin gestations and compare them to previously published normograms. Methods A retrospective analysis of sEFW evaluations of twin gestations was performed between 2011 and 2016 in a single university-affiliated medical center. sEFW was calculated using the Hadlock 1985 formula. To avoid selection bias, one evaluation per pregnancy was randomly selected. Following mathematical transformation to obtain normality of values, normograms were constructed using a best-fit regression model for estimation of mean and standard deviation at each gestational age (GA). Normograms were validated by applying all observations to ensure equal distribution at parallel percentiles. Our normograms were then compared to previously published sEFW normograms for twin gestations. Results A total of 864 sEFW evaluations were performed on 195 twin pregnancies at 22-39 gestational weeks. Of them, 390 entered the primary analysis. The rest were left for validation. Seventy percent of the cohort were dichorionic-diamniotic twins (136/195), 16% (32/195) were monochorionic-diamniotic twins and three (1.5%) were monochorionic-monoamniotic twins. Twenty-four fetuses lacked data on chorionicity. The rest were monochorionic twins or were of unknown chorionicity. Values corresponding to the 2.5th, 10th, 50th, 90th and 97.5th percentiles for sEFW are presented for every GA. Validation by applying all 864 evaluations on constructed normograms was achieved. Comparison to previously published twins' sEFW normograms demonstrated wide variation between curves. Conclusion New reference values for biometrical measurements and sEFW in twin gestations are presented for clinical and research use. Comparison to other curves demonstrates the wide variability and need for further investigation on twin's normal growth.

Fetal growth standards for Somali population

BACKGROUND

Accurate assessment of fetal size is essential in providing optimal prenatal care. National Institute of Child Health and Human Development (NICHD) study from 2015 demonstrated that estimated fetal weight (EFW) differed significantly by race/ethnicity after 20 weeks. There is a large Somali population residing in Minnesota, many of whom are cared for at our maternal fetal medicine practice at the University of Minnesota. Anecdotally, we noticed an increased proportion of small-for-gestational age diagnoses within this population. We sought to use our ultrasound data to create a reference standard specific for this population and compare to currently applied references.

PURPOSE

We aimed to model fetal growth standards within a healthy Somali population between 16 and 40 weeks gestation, and address possible differences in the growth patterns compared with standards for non-Hispanic White, non-Hispanic Black, Hispanic, and Asian singleton fetuses published by the NICHD in the Fetal Growth Study.

MATERIALS AND METHODS

This is a retrospective cohort study using ultrasound data from 527 low risk pregnancies of Somali ethnicity at single tertiary care center between 2011 and 2017. A total of 1107 scans were identified for these pregnancies and maternal and obstetrical data were reviewed. Women 18-40 years of age with low-risk pregnancies and established dating consistent with first trimester ultrasound scan were included. Exclusion criteria were any maternal, fetal or obstetrical conditions known to affect fetal growth.

RESULTS

Estimated fetal weight among Somali pregnancies differed significantly at some time points from the NICHD four ethnic groups, but generally the EFW graph curves crossed over at most time points between the study groups. At week 18, EFW was significantly larger than all other four ethnic groups (all p<.001), it was also significantly larger from the Hispanic, Black, and Asian ethnic groups at some time points between 18 and 27 weeks gestation (p < .05). Additionally, EFW among Somali pregnancies was significantly smaller than the Black and Asian ethnicity at 32 and 35-36 weeks and smaller than the White ethnicity at 30 and 38-39 weeks (p < .05). Abdominal circumference (AC) for the Somali population was significantly smaller than the other ethnic groups, especially than the White ethnicity at various time points across 16-40 weeks (p < .05). Femur and humerus length were significantly longer when compared to all other ethnic groups at most time points from 16 to 40 weeks of gestation (p < .05). Biparietal diameter (BPD) was significantly smaller than all other ethnic groups specifically at time of fetal survey (18 weeks) and at time of fetal growth assessment (32 weeks) (p < .05).

CONCLUSIONS

Significant differences in fetal growth standards were found between the Somali ethnicity and other ethnic groups (White, Black, Asian, and Hispanic) at various time points from 16 to 40 weeks of gestation. Racial/ethnic-specific standards improve the precision for evaluating fetal growth and may decrease the proportion of fetuses of Somali ethnicity labeled as small-for-gestational age.

Effects of a formula with a probiotic Bifidobacterium lactis Supplement on the gut microbiota of low birth weight infants

PURPOSE

Low birth weight (LBW) infants have a less diverse gut microbiota, enriched in potential pathogens, which places them at high risk of systemic inflammation diseases. This study aimed to identify the differences in gut bacterial community structure between LBW infants who received probiotics and LBW infants who did not receive probiotics.

METHODS

Forty-one infants were allocated to the non-probiotic group (N group) and 56 infants to the probiotic group (P group), according to whether the formula they received contained a probiotic Bifidobacterium lactis. Gut bacterial composition was identified with sequencing of the 16S rRNA gene in fecal samples collected at 14 days after birth.

RESULTS

There was no significant difference between the alpha diversity of the two groups, while the beta diversity was significantly different (p < 0.05). Our results showed that Bifidobacterium and Lactobacillus (both p < 0.05) were enriched in the P group, while Veillonella, Dolosigranulum and Clostridium sensu stricto 1 (all p < 0.05) were enriched in the N group. Predicted metagenome function analysis revealed enhancement of fatty acids, peroxisome, starch, alanine, tyrosine and peroxisome pathways in the P group, and enhancement of plant pathogen, Salmonella and Helicobacter pylori infection pathways in the N group.

CONCLUSIONS

Probiotic supplement in formula may affect the composition, stability and function of LBW infants' gut microbiota. LBW infants who receive probiotic intervention may benefit from gut microbiota that contains more beneficial bacteria.

Serum podocalyxin at 11-13 weeks of gestation in the prediction of small for gestational age neonates

OBJECTIVE

To investigate a potential new marker for the prediction of small for gestational age (SGA) infants.

STUDY DESIGN

Nested case-control study involving 280 uncomplicated pregnancies and 70 cases of SGA without pre-eclampsia. Serum podocalyxin was measured at 11-13 weeks of gestation and results were expressed in multiples of the median (MoM). The performance of screening by a combination of maternal history and podocalyxin levels was assessed with ROC curves.

RESULTS

SGA was predicted by maternal age, height, South Asian ethnicity, and previous delivery without pre-eclampsia. Median podocalyxin levels were higher in affected than uncomplicated pregnancies (1.303 versus 0.994 MoM, p < 0.001). At a 10% false-positive rate, maternal history identified 40.0% of the cases (AUC = 0.74, 95%CI 0.671-0.809). The addition of podocalyxin increased the detection to 54.3% (AUC = 0.78, 95%CI 0.771-0.842, p = 0.027 for the difference in ROC curves).

CONCLUSION

First-trimester podocalyxin may be useful in screening for SGA infants.

Comparison of fetal size standards obtained with conventional methods and individualized assessment: the effect of adjusting for differences in growth potential

Objective: Detection of fetal growth restriction depends on the biometric standard definitions of normal variability. We examined the impact of correcting for differences in fetal growth potential on the variability of third-trimester size standards.Methods: Size standards, corrected differences in growth potential using Individualized Growth Assessment [IGA], were obtained in 119 pregnancies with normal neonatal growth outcomes. Using the same cohort, a second set of size standards, without these corrections, were determined with mixed modeling [IGA Cross-sectional]. An independent set of size standards, obtained by quantile regression in a population-based sample of 1387 pregnant women [World Health Organization (WHO)], was also evaluated. The anatomical parameters studied included BPD, HC, AC, FDL, THC, HDL, ArmC and EWT whenever possible. The variability measures compared were percent deviation reference range [IGA] or twice the coefficient of variation [IGA Cross-sectional, WHO] at weekly time points between 28 and 38 weeks, menstrual age.Results: All six IGA variabilities were significantly smaller [range: 19-60%] when IGA and IGA-cross-sectional size standards were compared. Similar IGA-WHO comparisons showed that the IGA variabilities for 5 of 6 anatomical parameters were significantly smaller [range: 26-32%; exception: FDL (5.8%)]. Comparisons of cross-sectional size standards gave variable results depending on the anatomical parameter studied.Conclusions: Third-trimester variability measures, based on IGA, were consistently lower than those obtained with conventional cross-sectional methods in normal pregnancies. These results were found when the identical sample was used in both IGA and cross-sectional analyses. Decreased variability can improve the sensitivity of IGA for detecting restricted growth and may be partly responsible for its ability to identify different types of growth abnormalities earlier in pregnancy.

A case for not adjusting birthweight customized standards for ethnicity: observations from a unique Australian cohort

BACKGROUND

Low birthweight is more common in infants of indigenous (Aboriginal and/or Torres Strait Islander) than of White Australian mothers. Controversy exists on whether fetal growth is normally different in different populations.

OBJECTIVE

We sought to determine the relationships of birthweight, birthweight percentiles, and smoking with perinatal outcomes in indigenous vs nonindigenous infants to determine whether the White infant growth charts could be applied to indigenous infants.

STUDY DESIGN

Data were analyzed for indigenous status, maternal age and smoking, and perinatal outcomes in 45,754 singleton liveborn infants of at least 20 weeks gestation or 400 g birthweight delivered in New South Wales, Australia, between June 2010 and July 2015.

RESULTS

Indigenous infants (n=6372; 14%) had a mean birthweight 67 g lower than nonindigenous infants (P<.0001; with adjustment for infant sex and maternal body mass index). Indigenous mean birthweight percentile was 4.2 units lower (P<.0001). Adjustment for maternal age, smoking, body mass index, and infant sex reduced the difference in birthweight/percentiles to nonsignificance (12 g; P=.07).

CONCLUSION

Disparities exist between indigenous and non-indigenous Australian infants for birthweight, birthweight percentile, and adverse outcome rates. Adjustment for smoking and maternal age removed any significant difference in birthweights and birthweight percentiles for indigenous infants. Our data indicate that birthweight percentiles should not be adjusted for indigenous ethnicity because this normalizes disadvantage; because White and indigenous Australians have diverged for approximately 50,000 years, it is likely that the same conclusions apply to other ethnic groups. The disparities in birthweight percentiles that are associated with smoking will likely perpetuate indigenous disadvantage into the future because low birthweight is linked to the development of chronic noncommunicable disease and poorer educational attainment; similar problems may affect other indigenous populations.

Mechanisms of death in structurally normal stillbirths

Objectives To investigate mechanisms of in utero death in normally formed fetuses by measuring amniotic fluid (AF) biomarkers for hypoxia (erythropoietin [EPO]), myocardial damage (cardiac troponin I [cTnI]) and brain injury (glial fibrillary acidic protein [GFAP]), correlated with risk factors for fetal death and placental histopathology. Methods This retrospective, observational cohort study included intrauterine deaths with transabdominal amniocentesis prior to induction of labor. Women with a normal pregnancy and an indicated amniocentesis at term were randomly selected as controls. AF was assayed for EPO, cTnI and GFAP using commercial immunoassays. Placental histopathology was reviewed, and CD15-immunohistochemistry was used. Analyte concentrations >90th centile for controls were considered "raised". Raised AF EPO, AF cTnI and AF GFAP concentrations were considered evidence of hypoxia, myocardial and brain injury, respectively. Results There were 60 cases and 60 controls. Hypoxia was present in 88% (53/60), myocardial damage in 70% (42/60) and brain injury in 45% (27/60) of fetal deaths. Hypoxic fetuses had evidence of myocardial injury, brain injury or both in 77% (41/53), 49% (26/53) and 13% (7/53) of cases, respectively. Histopathological evidence for placental dysfunction was found in 74% (43/58) of these cases. Conclusion Hypoxia, secondary to placental dysfunction, was found to be the mechanism of death in the majority of fetal deaths among structurally normal fetuses. Ninety-one percent of hypoxic fetal deaths sustained brain, myocardial or both brain and myocardial injuries in utero. Hypoxic myocardial injury was an attributable mechanism of death in 70% of the cases. Non-hypoxic cases may be caused by cardiac arrhythmia secondary to a cardiac conduction defect.

Cystatin C as a novel predictor of preterm labor in severe preeclampsia

Background

The most common cause of acute kidney injury (AKI) in pregnancy is preeclampsia. Serum cystatin C (CysC) is a potential biomarker of early kidney damage as its levels are not disturbed by volume status changes in pregnancy, and serum CysC levels could serve as a replacement for conventionally used creatinine. In this study, we investigated the serum levels of CysC in severe preeclampsia cases and the associations between CysC levels and poor obstetric outcomes.

Methods

Our cohort included severe preeclampsia patients with a normal serum creatinine level. Creatinine was measured to calculate estimated glomerular filtration rate (eGFR) based on the Cockcroft and Gault, Modification of Diet in Renal Disease Study (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations, while CysC was measured to calculated eGFR based on a CysC-based equation. We then evaluated the correlations between serum CysC level, eGFR, and obstetric outcomes.

Results

Twenty-six patients were evaluated of which 38.5% delivered preterm and 30.8% had low-birth weight babies. Unlike creatinine-based eGFR and CysC-based eGFR, serum CysC demonstrate significant negative correlation with gestational age. Receiver operating characteristic curve analysis indicated that serum CysC is a potential biomarker of preterm delivery with a cut-off serum level of 1.48 mg/L with 80% sensitivity and 75% specificity.

Conclusion

GFR estimation using CysC is likely to be inaccurate in pregnancy. However, we found a significant correlation between preterm delivery and serum CysC level. Our results suggest that serum CysC level has the potential to predict preterm delivery in severe preeclampsia patients.

Does prenatal identification of fetal macrosomia change management and outcome?

PURPOSE

To assess whether there is an association between predicted fetal macrosomia and adverse outcomes in macrosomic newborns (> 4000 g), based on a sonographic evaluation up to 2 weeks prior to delivery.

METHODS

A retrospective cohort study of 3098 mothers of macrosomic babies who were delivered at our institution (2000-2015). We compared the management and outcomes of women with predicted fetal macrosomia with that of women with unknown fetal macrosomia. The primary outcomes were cesarean section (CS) rate and postpartum hemorrhage. Secondary outcomes were composite maternal and neonatal outcomes and birth injuries.

RESULTS

In 601 (19.4%) women fetal macrosomia was predicted, and in 2497 (80.6%) women, fetal macrosomia was unknown. CS rate was more than 3.5 times higher in the group of predicted macrosomia (47.2% vs. 12.7%, P < 0.001) than those with unpredicted macrosomia; not only due to non-progressive labor, but for non-reassuring heart rate as well. However, predicted fetal macrosomia reduced the risk of postpartum hemorrhage (aOR 0.5, 95% CI 0.2-1.0), maternal (aOR 0.3, 95% CI 0.2-0.5) and neonatal composite adverse outcomes (aOR 0.7 95% CI 0.6-0.9). It was also associated with increased risk for induction of labor, episiotomy, 3rd- or 4th-degree tears and a longer maternal hospitalization. Birth injuries and shoulder dystocia were not different between the groups.

CONCLUSIONS

Antepartum CS was found to be associated with predicted fetal macrosomia. Moreover, a planned CS due to macrosomia was associated with reduced risk for postpartum hemorrhage, maternal and neonatal outcome, even for babies with a mean birth weight < 4500 g.

Mapping the landscape of global programmes to evaluate health interventions in pregnancy: the need for harmonised approaches, standards and tools

Pregnant women and their babies are among the populations most vulnerable to untoward health outcomes. Yet current standards for evaluating health interventions cannot be met during pregnancy because of lack of adequate evidence. The situation is even more concerning in low-income and middle-income countries, where the need for effective interventions is the greatest. Meeting the Sustainable Development Goals for health will require strengthened attention to maternal and child health. In this paper we examine ongoing initiatives aimed at improving the assessment of maternal interventions. We review current methodologies to monitor outcomes of maternal interventions and identify where harmonisation is needed. Based on this analysis we identify settings where different minimal data sets should be considered taking into consideration the clinical realities. Stronger coordination mechanisms and a roadmap to support harmonised monitoring of maternal interventions across programmes and partners, working on improving pregnancy and early childhood health events, will greatly enhance ability to generate evidence-based policies.