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.

Detection and Quantification of Neurotrophin-3 (NT-3) and Nerve Growth Factor (NGF) Levels in Early Second Trimester Amniotic Fluid: Investigation into a Possible Correlation with Abnormal Fetal Growth Velocity Patterns

BACKGROUND

Abnormal fetal growth is associated with adverse perinatal and long-term outcomes. The pathophysiological mechanisms underlying these conditions are still to be clarified. Nerve growth factor (NGF) and neurotrophin-3 (NT-3) are two neurotrophins that are mainly involved in the neuroprotection process, namely promotion of growth and differentiation, maintenance, and survival of neurons. During pregnancy, they have been correlated with placental development and fetal growth. In this study, we aimed to determine the early 2nd trimester amniotic fluid levels of NGF and NT-3 and to investigate their association with fetal growth.

METHODS

This is a prospective observational study. A total of 51 amniotic fluid samples were collected from women undergoing amniocentesis early in the second trimester and were stored at -80 °C. Pregnancies were followed up until delivery and birth weight was recorded. Based on birth weight, the amniotic fluid samples were divided into three groups: appropriate for gestational age (AGA), small for gestational age (SGA), and large for gestational age (LGA). NGF and NT-3 levels were determined by using Elisa kits.

RESULTS

NGF concentrations were similar between the studied groups; median values were 10.15 pg/mL, 10.15 pg/mL, and 9.14 pg/mL in SGA, LGA, and AGA fetuses, respectively. Regarding NT-3, a trend was observed towards increased NT-3 levels as fetal growth velocity decreased; median concentrations were 11.87 pg/mL, 15.9 pg/mL, and 23.5 pg/mL in SGA, AGA, and LGA fetuses, respectively, although the differences among the three groups were not statistically significant.

CONCLUSIONS

Our findings suggest that fetal growth disturbances do not induce increased or decreased production of NGF and NT-3 in early second trimester amniotic fluid. The trend observed towards increased NT-3 levels as fetal growth velocity decreased shows that there may be a compensatory mechanism in place that operates in conjunction with the brain-sparing effect. Further associations between these two neurotrophins and fetal growth disturbances are discussed.

Evaluation of ultrasound measurements of abdominal fat for the prediction of gestational diabetes in the first and second trimesters of pregnancy

OBJECTIVE

To evaluate whether ultrasound abdominal fat measurements in the first and second trimesters can predict adverse gestational outcomes, particularly gestational diabetes mellitus (GDM), and identify early patients at higher risk for complications.

METHODS

A prospective cohort study of 126 pregnant women at 11-14 and 20-24 weeks of gestation with normal fasting glucose levels during early pregnancy. From 126 participants with complete data, 13.5% were diagnosed with GDM, based on the cutoffs established for the peripherical blood glucose. Subcutaneous, visceral, and maximum preperitoneal abdominal fat were measured using ultrasound techniques. GDM status was determined by oral glucose tolerance test (OGTT) with 75 g glucose overload, and the following values were considered abnormal: fasting glucose ≥92 mg/dl and/or 1 h after overload ≥180 mg/dl and/or 2 h after overload ≥153 mg/dl. The receiver operator characteristic (ROC) curve was used to determine the optimal threshold to predict GDM.

RESULTS

Maximum preperitoneal fat measurement was predictive of GDM, and subcutaneous and visceral abdominal fat measurements did not show significant differences in the prediction of GDM. According to the ROC curve, a threshold of 45.25 mm of preperitoneal fat was identified as the optimal cutoff point, with 87% sensitivity and 41% specificity to predict GDM. The raw and adjusted odds ratios for age and pre-pregnancy body mass index were 0.730 (95% confidence interval [CI], 0.561-0.900) and 0.777 (95% CI, 0.623-0.931), respectively.

CONCLUSION

The use of a 45.25 mm threshold for maximum preperitoneal fat, measured by ultrasound to predict the risk of GDM, appears to be a feasible, inexpensive, and practical alternative to incorporate into clinical practice during the first trimester of pregnancy.

Neutrophil count is a useful marker to predict the severity of preeclampsia

BACKGROUND

At present, pre-eclampsia is a growing concern and still a diagnostic challenge for obstetricians.

AIMS

This study aimed to evaluate whether the relationship of second trimester of pregnancy neutrophil count differed among pregnancies with mild preeclampsia, severe preeclampsia, and healthy status and explore whether or not neutrophil count in the second trimester of pregnancy would be useful as new predictors of subsequent preeclampsia.

PATIENTS AND METHODS

This study involved 933 pregnancies from 1 January 2018 to 30 January 2021, comprising 396 healthy pregnancies, 222 pregnancies with mild preeclampsia, and 315 pregnancies with severe preeclampsia. The relationship between preeclampsia and neutrophil count was analyzed by multiple logistic regression. In addition, maternal placental tissues of three groups were immunohistochemically stained for myeloperoxidase (MPO).

RESULTS

Neutrophil count was significantly higher in pregnancies with preeclampsia (including pregnancies with mild and severe preeclampsia) than that in healthy pregnancies. The neutrophil count level was prominently higher in patients with severe preeclampsia compared with those with mild preeclampsia (p < .001). The neutrophil count level was significantly positively associated with preeclampsia after adjusting for gestational week at time of blood sampling, BMI, and age (β:1.23; 95%CI:1.09-1.36; p < .0001). In addition, MPO expressions of placental tissues in preeclamptic groups were significantly increased than these in healthy pregnant controls (p < .05).

CONCLUSIONS

Increased neutrophil count in the second trimester of pregnancy was significantly positively associated with preeclampsia. Hence, neutrophil count plays a role in predicting the severity of preeclampsia. At the same time, it may be an independent predictor of subsequent preeclampsia.Abbreviations: BMI: body mass index; MPO: myeloperoxidase.

Second trimester cervical length measurements with transvaginal ultrasound: A prospective observational agreement and reliability study

INTRODUCTION

Universal screening for preterm delivery by adding transvaginal ultrasound measurement of cervical length to routine second trimester ultrasound has been proposed. The aim is to estimate inter- and intraobserver agreement and reliability of second trimester transvaginal ultrasound measurements of cervical length performed by specially trained midwife sonographers.

MATERIAL AND METHODS

This is a prospective reliability and agreement study performed in seven Swedish ultrasound centers. In total, 18 midwife sonographers specially trained to perform ultrasound measurements of cervical length and 286 women in the second trimester were included. In each center, two midwife sonographers measured cervical length a few minutes apart in the same woman, the number of women examined per examiner pair varying between 24 and 30 (LIVE study). Sixteen midwife sonographers measured cervical length twice ≥2 months apart on 93 video clips (CLIPS study). The main outcome measures were mean difference, limits of agreement, intraclass correlation coefficient, intra-individual standard deviation, repeatability, Cohen's kappa and Fleiss kappa.

RESULTS

The limits of agreement and intraclass correlation coefficient of the best examiner pair in the LIVE study were -4.06 to 4.72 mm and 0.91, and those of the poorest were -11.11 to 11.39 mm and 0.31. In the CLIPS study, median (range) intra-individual standard deviation was 2.14 mm (1.40-3.46), repeatability 5.93 mm (3.88-9.58), intraclass correlation coefficient 0.84 (0.66-0.94). Median (range) interobserver agreement for cervical length ≤25 mm in the CLIPS study was 94.6% (84.9%-98.9%) and Cohen's kappa 0.56 (0.12-0.92), median (range) intraobserver agreement was 95.2% (87.1%-98.9%) and Cohen's kappa 0.68 (0.27-0.93).

CONCLUSIONS

Agreement and reliability of cervical length measurements differed substantially between examiner pairs and examiners. If cervical length measurements are used to guide management there is potential for both over- and under-treatment. Uniform training and rigorous supervision and quality control are advised.

Effect of abnormal GpG methylation in the second trimester of pregnancy on adverse health risk of offspring

Effect of abnormal GpG methylation in amniotic fluid cells during the second trimester of pregnancy on adverse health risk of offspring was investigated. In total, 237 sets of amniotic fluid cells were collected from patients who received prenatal diagnosis in the Third Affiliated Hospital of Guangzhou Medical University (Guangzhou, China) from April 2010 to October 2011. Among them, 156 sets were from singleton and 81 sets were from twins. H19 gene was amplified by PCR, and the product was purified and pyrosequencing was used to detect the DNA methylation level of GapG. Follow-up records of the birth outcomes of pregnant women's offspring were collected. Positive rate of DNA amplification in 200 cases of amniotic fluid cells was 84.4% (200/237). Average age of singleton pregnancies was higher than that of twins (P<0.05), and no significant differences were found in gestational age and PCR amplification rate (P>0.05). There was no difference in the methylation level of GapG between singleton and twins (P>0.05), but the abnormal methylation rate of GapG1 in twin fetuses was significantly higher than that of singleton (20.3 vs. 3.6%, χ²=8.364, P=0.004). Offspring sex, singleton or twins, mode of delivery, time of pregnancy, and low birth weight showed no significant effect on GapG methylation level of H19 in the second trimester of pregnancy. No offspring deformities were found regardless of the increased or decreased degree of methylation (P>0.05). The number of fetuses born may cause abnormal GapG1 methylation, but no effect of GapG methylation on the adverse health risk of offspring was found.

Comparative Evaluation of Arabin Pessary and Cervical Cerclage for the Prevention of Preterm Labor in Asymptomatic Women with High Risk Factors

Objective: Preterm labor is one of the most significant obstetric problems associated with high rate of actual and long-term perinatal complications. Despite the creation of scoring systems, uterine activity monitoring, cervical ultrasound and several biochemical markers, the prediction and prevention of preterm labor is still a matter of concern. The aim of this study was to examine cervical findings for the prediction and the comparative use of Arabin pessary or cerclage for the prevention of preterm birth in asymptomatic women with high risk factors for preterm labor. Material and methods: The study group was composed of singleton pregnancies (spontaneously conceived) with high risk factors for preterm labor. Cervical length, dilatation of the internal cervical os and funneling, were estimated with transvaginal ultrasound during the first and the second trimesters of pregnancy. Results: Cervical funneling, during the second trimester of pregnancy, was the most significant factor for the prediction of preterm labor. The use of Arabin cervical pessary was found to be more effective than cerclage in the prolongation of pregnancy. Conclusion: In women at risk for preterm labor, the detection of cervical funneling in the second trimester of pregnancy may help to predict preterm labor and to apply the appropriate treatment for its prevention. Although the use of cervical pessary was found to be more effective than cerclage, more studies are needed to classify the effectiveness of different methods for such prevention.