The impact of preimplantation genetic testing on prenatal diagnostic procedures

OBJECTIVE

In recent years, cell-free DNA screening has significantly reduced the number of invasive prenatal diagnostic testing in pregnancy. Preimplantation genetic testing for aneuploidies (PGT-A) is a commonly performed screening test in in vitro fertilization (IVF) pregnancies. Therefore, we aimed to determine the impact of PGT-A on subsequent utilization of prenatal diagnostic testing in IVF pregnancies.

METHODS

Retrospective cohort of singleton and twin IVF pregnancies at a single center from January 2014 to December 2017. The rate of invasive diagnostic genetic testing (chorionic villus sampling (CVS) and/or amniocentesis) was compared between patients with pregnancies achieved after transfer of a euploid embryo by PGT-A (n = 71) and those with pregnancies achieved after transfer of an untested embryo (n = 38). Wilcoxon rank sum and Fisher's exact tests were used for statistical analysis.

RESULTS

There was no statistically significant difference in the number of prenatal diagnostic procedures (25.4% PGT-A euploid embryo versus 31.6% untested embryo, p = .51 and p = .32 for one-sided and two-sided analyses, respectively) between the two groups. Maternal age, nuchal translucency measurements and the rate of abnormal sonographic findings were similar between the two groups. Patients without PGT-A pregnancies had a higher BMI (mean 29.6, p = .01) and were ethnically different (p = .013) compared to those with PGT-A.

CONCLUSION

The implementation of PGT-A in IVF patients did not reduce the number of invasive diagnostic tests performed at our institution.

Oxidative stress - Related spontaneous preterm delivery challenges in causality determination, prevention and novel strategies in reduction of the sequelae

Spontaneous preterm birth (PTB) is one of the major complications of pregnancy and the main cause of neonatal mortality and morbidity. Despite the efforts devoted to the understanding of this obstetrical syndrome and improved medical care, there has been a tendency for the PTB rate to increase in the last decades globally. The costs of the screening for spontaneous PTB, its management, and treatment of the sequelae represent a major burden to the health service economy of high-income countries. In this scenario, it has been widely acknowledged that oxidative stress (OS) plays an important role in the pathogenicity of human disease in wide range of areas of medicine. There is an emerging evidence that an imbalance between pro-and-antioxidants may be associated with spontaneous PTB. However, there are still many controversies on the mechanisms by which OS are involved in the pathogenesis of prematurity. Moreover, the crucial question whether the OS is the cause or consequence of the disease is yet to be answered. The purpose of this article is to briefly summarize the current knowledge and controversies on oxidative stress-related spontaneous PTB and to give a critical approach on future perspectives on this topic as a classical example of translational medicine. Placenta-mediated pregnancy adverse outcome associated with OS leading to iatrogenic PTB (e.g. pre-eclampsia, intrauterine growth restriction, gestational diabetes) will not be discussed.

Equine fetal genotyping via aspiration of yolk-sac fluid at 22-28 days of gestation

Fetal genotyping has important applications in the horse, but currently necessitates embryo recovery and biopsy. We investigated whether fetal genotyping could be performed on yolk-sac fluid recovered from pregnant mares via transvaginal aspiration. Fluid was collected before Day 30 to provide results before establishment of the endometrial cups (Day 37). Genotyping and assessment of maternal DNA contamination was performed by analyzing histograms of PCR results for 19 loci. In Exp. 1, mares underwent yolk-sac aspiration on Days 22-28 of gestation. Fluid (0.56-1.02 mL) was recovered from five of seven mares. Four of the five mares maintained pregnancy. One pregnancy was electively terminated at Day 75; the other three mares delivered healthy foals. Extraction of DNA from the fluid sample followed by direct PCR allowed the highest rate of determination of fetal alleles. Fetal genotype was correctly determined in three samples, and for 14/19 alleles in one sample. In Exp. 2, we evaluated whether recovery of more fluid (up to 1.6 mL), and fractionation of the sample, would minimize maternal DNA contamination. One of four mares maintained pregnancy. Evaluation at informative loci showed no difference in maternal contamination among fractions. We determined that mares can maintain pregnancy after aspiration of yolk-sac fluid, and that fetal genotype can be accurately determined from the sample obtained. Further work is needed on factors affecting maintenance of pregnancy after the procedure. The ability to access the yolk sac in early pregnancy opens the door to novel potential clinical and research applications.

Comparison of obstetrical outcomes in patients undergoing cerclage with or without amniocentesis

OBJECTIVE

We sought to compare the obstetrical outcomes in patients who underwent midtrimester cerclage placement with or without prior amniocentesis in a single center cohort.

METHODS

A retrospective medical record review in a single academic institution was undertaken of all patients who underwent either an exam or ultrasound indicated cerclage. This group was then divided into two groups: amniocentesis or no amniocentesis groups. Detailed maternal data was abstracted from the prenatal and hospital records. Amniocentesis fluid specimens were sent for Gram stain, aerobic and anaerobic bacterial culture, including mycoplasma and ureaplasma, as well as for glucose. Comparisons were performed utilizing Parametric 2-sample t-test for continuous variables and Fisher's exact test was utilized to compare categorical variables.

RESULTS

A total of 160 patients who underwent a cerclage were utilized for comparison. Sixty-five patients who had an amniocentesis performed prior to the cerclage were compared with 95 patients who underwent a cerclage without an amniocentesis. None of the amniocentesis results were positive for infection in those that received a cerclage. Patients that had an amniocentesis before cerclage were found to have an earlier gestational age at time of the procedure (20.30 ± 2.29 weeks versus 21.32 ± 1.81 weeks, p < .001), a shorter cervical length on presentation (0.93 ± 0.61 cm versus 1.45 ± 0.66 cm, p < .001), delivered at an earlier gestational age (GA 32.2 [30.3 to 34.2] versus 36.3 [35.2 to 37.3] weeks, p < .001) with shorter time from cerclage placement until delivery (13.9 [0.0 to 24.0] versus 16.3 [0.3 to 23.2] weeks, p = .010). The rates of chorioamnionitis and PPROM were significantly higher in the amniocentesis group (17 versus 2%, p = .0008 and 26 versus 13%, p = .03 respectively). Five patients who underwent an amniocentesis did not receive a cerclage, with one having a positive Gram stain and culture.

CONCLUSION

Amniocentesis use prior to cerclage placement in this single institution cohort was utilized in patients who presented earlier in gestation with shorter cervical length and more cervical dilation. The severity of presentation was the determining factor in the decision to perform an amniocentesis prior to cerclage placement, and, because of this difference in severity, outcomes for the amniocentesis group were predictably worse than those who did not undergo amniocentesis.

Sex specific relationships between infants' mental rotation ability and amiotic sex hormones

Sex differences in mental rotation, robust in adults, have recently been reported for infants' looking times although the pattern of results is not completely conclusive. In this context, organizational effects of gonadal steroids affecting the neural circuitry underlying spatial cognition could be (partly) responsible for the early sex difference. In the present study testosterone and estradiol levels measured in amniotic fluid via ultra performance liquid chromatography and tandem mass spectrometry were used to examine the role of prenatal sex hormones on infants' looking times during mental rotation. N = 208 six-month-old infants participated in an expectation of violation task with 3D cube figures. Mental rotation was defined as the difference in looking times for familiar versus mirrored cube figures whereas vigilance was defined as the sum of both looking times. Sex differences were absent for mental rotation as well as for vigilance. Most importantly, however, for boys mental rotation but not vigilance was correlated with prenatal testosterone but not with estradiol. For girls mental rotation but not vigilance was correlated with prenatal estradiol but not with testosterone although it has to be noted that the testosterone values for girls suffered from a floor effect. Only 5% of the within-sex variance was due to prenatal sex hormones indicating small effects. These findings extend our knowledge concerning organizational effects of prenatal sex hormones on the brain circuitry underlying spatial cognition.

Prenatal testosterone exposure is associated with delay of gratification and attention problems/overactive behavior in 3-year-old boys

Sex differences in self-control become apparent during preschool years. Girls are better able to delay their gratification and show less attention problems and overactive behavior than boys. In this context, organizational effects of gonadal steroids affecting the neural circuitry underlying self-control could be responsible for these early sex differences. In the present study testosterone levels measured in amniotic fluid (via ultra performance liquid chromatography and tandem mass spectrometry) were used to examine the role of organizational sex hormones on self-control. One hundred and twenty-two 40-month-old children participated in a delay of gratification task (DoG task) and their parents reported on their attention problems and overactive behavior. Girls waited significantly longer for their preferred reward than boys, and significantly more girls than boys waited the maximum period of time, providing evidence for sex differences in delay of gratification. Boys that were rated as suffering from more attention problems and overactive behavior waited significantly shorter in the DoG task. Amniotic testosterone measures were reliable in boys only. Most importantly, boys who waited shorter in the DoG task and boys who were reported to suffer from more attention problems and overactive behavior had higher prenatal testosterone levels. These findings extend our knowledge concerning organizational effects of testosterone on the brain circuitry underlying self-control in boys, and are of relevance for understanding how sex differences in behavioral disorders are connected with a lack of self-control.

Single or double needle insertion in twin's amniocentesis: Does the technique influence the risk of complications?

OBJECTIVE

To compare complication rates following amniocentesis in twin gestations, according to sampling technique and number of needle insertions.

STUDY DESIGN

A retrospective cohort study of all women with twin gestations who underwent amniocentesis and delivered in a single university affiliated medical center during 2002-2016. Amniocentesis was performed either through one uterine entry with passage through the inter-twin membrane or through two different entries to the two amniotic sacs. Pregnancy outcome of women that underwent single needle insertion amniocentesis, was compared to this of double needle insertion. Primary outcome was neonatal complications within 4 weeks after amniocentesis (late abortion, chorioamnionitis, preterm premature rupture of membranes, or hospitalization due to related symptoms). Secondary outcomes were gestational week at delivery and labor characteristics.

RESULTS

The study group comprised 212 women. Of them, 73 (34.4%) underwent a single uterine insertion and 139 (65.6%) two separate needle insertions. Baseline characteristics did not differ between the groups. The amniocentesis complication rate was 13.7% in the single insertion group and 16.5% in the double insertion group (p = 0.587). Multivariate analysis found that a single insertion method had no statistically significant influence on complication rate, after making adjustments for potential confounders (OR = 1.085, 95% CI 0.4-2.9; p = 0.871). Other labor characteristics were similar between the groups.

CONCLUSION

Needle insertion technique in twin gestation amniocentesis was not associated with procedure related complications.

Obstetrical Outcomes of Amniocentesis or Chorionic Villus Sampling in Dichorionic Twin Pregnancies

BACKGROUND

Under certain situations, women with twin pregnancies may be counseled to undergo invasive prenatal diagnostic testing. Chorionic villus sampling and amniocentesis are the two generally performed invasive prenatal diagnostic tests. Studies comparing procedure-related fetal loss between first-trimester chorionic villus sampling and second-trimester amniocentesis in twin pregnancies are limited. This study aimed to evaluate the procedure-related fetal loss and the obstetrical outcomes of these two procedures, chorionic villus sampling and amniocentesis in twin pregnancies.

METHODS

The data from dichorionic-diamniotic twin pregnancies on which first-trimester chorionic villus sampling (n = 54) or second-trimester amniocentesis (n = 170) was performed between December 2006 and January 2017 in a single center were retrospectively analyzed. The procedure-related fetal loss was classified as loss of one or all fetuses within 4 weeks of procedure, and overall fetal loss was classified as loss of one or all fetuses during the gestation. The groups were compared with respect to the procedure-related and obstetrical outcomes.

RESULTS

The difference in proportion of procedure-related fetal loss rate (1.9% for chorionic villus sampling vs. 1.8% for amniocentesis; P = 1.000) and the overall fetal loss rate (7.4% for chorionic villus sampling vs. 4.7% for amniocentesis; P = 0.489) between the two groups was not significant. The mean gestational ages at delivery were not statistically significant.

CONCLUSION

Both the overall fetal loss rate and the procedure-related fetal loss rate of chorionic villus sampling and amniocentesis in dichorionic twin pregnancies had no statistical significance. Both procedures can be safely used individually.

Value of increased nuchal translucency in the era of noninvasive prenatal testing with cell-free DNA

OBJECTIVE

To assess the value of increased nuchal translucency (NT) at first-trimester screening (FTS) despite the superiority of noninvasive prenatal testing with cell-free DNA (cfDNA) for the detection of fetal aneuploidies.

METHODS

Retrospective analysis of all FTS data from 2005 to 2015 in our department. Only cases with increased NT and euploid karyotype were considered eligible for inclusion. Abnormal findings, diagnostic work-up, and perinatal outcomes were assessed.

RESULTS

Of 18 084 FTS results, 460 (2.5%) showed increased fetal NT, of which 242 (52.6%) underwent invasive karyotyping and 179 (74.0%) had an aneuploidy. Of the remaining 63 cases, 61 (96.8%) showed an additional sonographic finding at FTS and25 (78.1%) had a major anomaly at the second trimester organ scan. The outcome was termination of pregnancy in 28 (44.4%) cases, fetal demise in 5 (7.9%), delivery of an infant with malformation in 21 (33.3%), and delivery of a healthy infant in 7 (11.1%) cases.

CONCLUSION

All cases with increased NT would have been detected by cfDNA or by a major sonographic anomaly not later than the second trimester. Routine use of cfDNA, a basic sonogram, and an organ scan could reduce unnecessary work-up and anxiety.

Complication rates after chorionic villus sampling and midtrimester amniocentesis: A 7-year national registry study

PURPOSE

To assess the complication rates following chorionic villus sampling (CVS) and midtrimester amniocentesis in Taiwan.

METHODS

This is a national registry-based cohort study from Taiwan. We included all women with singleton pregnancies who received either CVS (n = 1409) or midtrimester amniocentesis (n = 250,566) during 2006-2012. We assessed preterm premature rupture of membranes (PPROM), intrauterine fetal demise (IUFD), infection and spontaneous abortion (SA) that occurred within fourteen days after the procedures. We also assessed the risks of preterm delivery and miscarriage before 24 gestational weeks after amniocentesis. These complications were collected from the Genetic Disease Database of the Ministry of Health and Welfare, Taiwan National Birth Certificate Registry, and the Taiwan National Health Insurance Database. Pearson χ² tests were used to compare the distributions between groups.

RESULTS

For patients who underwent midtrimester amniocentesis, the rates of PPROM, IUFD, infection and SA within fourteen days were 0.24%, 0.11%, 0.05%, and 0.05%, respectively. Women with a normal fetal karyotype had a preterm birth rate (<37 gestational weeks) of 9.38%. The miscarriage rate (<24 gestational weeks) was 0.68%, which was 0.22% higher than those who did not receive the invasive procedures (p < 0.0001). After CVS, the IUFD rate was 1.68%, and the SA rate within fourteen days was 0.77%.

CONCLUSION

The use of our large cohort demonstrated that the procedure-related complication rates were comparable to recent review or meta-analysis. This dataset might facilitate counselling in women who consider invasive genetic diagnostic procedures.

The combination of maternal blood and amniotic fluid biomarkers improves the predictive accuracy of histologic chorioamnionitis

INTRODUCTION

This study was performed to determine whether the combination of maternal blood and amniotic fluid biomarkers can improve the predictive accuracy of histologic chorioamnionitis (HC).

METHODS

This retrospective study included 80 singleton pregnant women who were suspected to have intrauterine infection and underwent measurement of two maternal blood biomarkers [maternal white blood cell count (mWBC) and maternal C-reactive protein level (mCRP)] and three amniotic fluid biomarkers [amniotic white blood cell count (aCell), amniotic glucose level (aGlucose), and amniotic lactate dehydrogenase level (aLDH)]. We divided the patients into two groups based on the presence or absence of HC and assessed the predictors of HC using logistic regression models: Model 1, combination of mWBC and mCRP; Model 2, combination of Model 1 and aGlucose; and Model 3, combination of Model 2, aCell, and aLDH.

RESULTS

The multivariable analysis showed that aCell was the only significant predictor of HC [odds ratio, 1.24; 95% confidence interval (CI), 1.06-1.68] independent of mWBC, mCRP, aGlucose, and aLDH. The c-statistics were higher in Model 3 (0.803; 95% CI, 0.701-0.905) than Model 1 (0.634; 95% CI, 0.511-0.758) and Model 2 (0.785; 95% CI, 0.684-0.887).

DISCUSSION

We found that the combination of maternal blood and amniotic fluid biomarkers can improve the predictive accuracy of HC. Therefore, our data provide relevant information to support counseling with regard to improving the predictive accuracy of HC in patients with suspected intrauterine infection.

Does Chorionic Villus Sampling Increase the Risk of Preeclampsia or Gestational Hypertension?

BACKGROUND

Chorionic villus sampling (CVS) and amniocentesis are two methods for prenatal diagnosis. The goal of this study was to compare amniocentesis and CVS-related complications in a large sample of Iranian women.

METHODS

Medical records of 1624 women who underwent amniocentesis or CVS due to medical indications between 2008 and 2016 were reviewed. Data regarding age, gravidity, parity, gestational age, type of procedure, neonatal weight (and percentile), trisomia, abortion, intrauterine growth restriction (IUGR), severe IUGR, preeclampsia, and gestational hypertension were recorded.

RESULTS

Finally, 1215 cases were evaluated. Mean maternal age, gravidity, and gestational age were significantly different between two groups. Preeclampsia, gestational hypertension, IUGR, severe IUGR, and intrauterine fetal death were not significantly different between two groups. Trisomy 18 and 21 were common in cases underwent amniocentesis.

CONCLUSIONS

Women who underwent CVS are not at higher risk for developing hypertensive disorders than women underwent amniocentesis.

Traditional Prenatal Diagnosis: Past to Present

In the nearly 60 years since prenatal diagnosis for genetic disease was first offered, the field of prenatal diagnosis has progressed far past rudimentary uterine puncture to provide fetal material to assess gender and interpret risk. Concurrent with the improvements in invasive fetal sampling came technological advances in cytogenetics and molecular biology that widened both the scope of genetic disorders that could be diagnosed and also the resolution at which the human genome could be interrogated. Nowadays, routine blood work available to all pregnant women can determine the risk for common chromosome abnormalities; chorionic villus sampling (CVS) and amniocentesis can be used to diagnose nearly all conditions with a known genetic cause; and the genome and/or exome of a fetus with multiple anomalies can be sequenced in an attempt to determine the underlying etiology. This chapter will discuss some of the major advances in prenatal sampling and prenatal diagnostic laboratory techniques that have occurred over the past six decades.

Detection of fetal trisomy 9 mosaicism by noninvasive prenatal testing through maternal plasma DNA sequencing

OBJECTIVE

Noninvasive prenatal testing (NIPT) is widely used as a powerful screening tool to detect common aneuploidies. However, its application for detection of rare chromosomal abnormalities remains inconclusive.

CASE REPORT

A 38-year-old woman (gravida 2, para 0) requested NIPT as a primary screening test for fetal aneuploidies at 13 weeks and 1 day of gestation. An unexpected Trisomy 9 (T9) abnormality was highly suspected. Amniocentesis was arranged for further diagnosis at 18 weeks of gestation. Final karyotyping reported 47,XX,+9 [18]/46,XX [12], indicating 60% T9 mosaicism.

CONCLUSION

This case shows strong evidence that NIPT can be a powerful screening tool to detect rare fetal trisomies at very early gestation.

Cytogenetic analysis in fetuses with late onset abnormal sonographic findings

OBJECTIVE

To determine the rate of chromosomal cytogenetic abnormalities in fetuses with late onset abnormal sonographic findings.

DESIGN

Retrospective cohort of women who underwent amniocentesis at or beyond 23 weeks of gestation, for fetal karyotype and chromosomal microarray analysis, indicated due to late onset abnormal sonographic findings.

RESULTS

All 103 fetuses had a normal karyotype. Ninety-five women also had chromosomal microarray analysis (CMA) performed. The detection rate of abnormal CMA (5/95, 5.3%) was similar to that of women who underwent amniocentesis due to abnormal early onset ultrasound findings detected at routine prenatal screening tests during the first or early second trimester (7.3%, P=0.46) and significantly higher than that for women who underwent amniocentesis and CMA upon request, without a medical indication for CMA (0.99%, P<0.0001).

CONCLUSIONS

Late onset sonographic findings are an indication for amniocentesis, and if performed, CMA should be applied to evaluate fetuses with late onset abnormal sonographic findings.

A Non-Lethal Osteogenesis Imperfecta Type II Mutation

BACKGROUND

We discuss the ethical decision points in a case report that describes a novel COL1A1 mutation associated to Osteogenesis Imperfecta type II, but with a non-lethal outcome.

CASE

A 33-year-old female underwent a 21-week ultrasound that revealed short bowed femurs and humeri with old fractures and bowed tibias and fibulas. Amniotic fluid testing revealed a novel COL1A1 mutation (c.1840G>A; p.Gly614Arg). OI Type II diagnosis was made. A previously reported mutation of the same gene but different locus (c.1840G>C; p.Gly614Arg) led to a lethal form of OI type II. The newborn was delivered via a cesarean delivery and intravenous bisphosphonates (Zaledronic acid) was administered every 3 months. Currently the infant is 22 months old, is growing, with mild bilateral conductive hearing loss.

CONCLUSION

The unexpected clinical outcome should serve as a reminder that phenotypic variability can occur with genetic mutations. Our case shows that the diagnosis of the type of OI should be based not only on clinical findings and genetic investigations but also on the clinical course over time.

Higher male prevalence of chromosomal mosaicism detected by amniocentesis

OBJECTIVE

To present the calculated frequencies, male to female sex-ratio, and modes of ascertainments in different levels of chromosomal mosaicism (CM) detected at amniocentesis.

MATERIALS AND METHODS

This's a 10-years retrospective study between January 2008 and December 2017 and there were 13,752 cases of amniocentesis performed in MacKay Memorial Hospital, Taipei, Taiwan. Eight hundred and thirty four cases of CM were collected in this study. We reviewed their types of chromosomal abnormalities of mosaicism, the modes of ascertainment (including: advanced maternal age, abnormal ultrasound findings, abnormal maternal serum screening result, and other reasons), maternal age, gestational age at amniocentesis, fetal gender, and perinatal findings. After amniocentesis, in situ culture was performed and the results of karyotype with CM were divided in to three levels.

RESULTS

In our sample of 13,752 amniocentesis, 834 cases with all levels of CM were collected in this study. Of them, there were 562 cases (4.09%) with level I mosaicism, 207 cases (1.51%) of level II mosaicism, and 65 cases (0.47%) of level III mosaicism (Table 1). In the group of advanced of maternal age (AMA), their calculated frequencies, 4.18% in level I, 1.46% in level II and 0.41% in level III, were very similar to those in total cases (p value = 0.206) without statistical significance. In the group of abnormal ultrasound findings, the calculated frequency was much higher in level III (0.87%), however, there was no statistical significance because of the small numbers of level III. In our cases of amniocentesis, the case numbers of male case (50.20%) is very similar to female (49.80%), and the male to female ratio was 1.01. But, we found more cases of male with CM (444 cases) than female (390 cases). The sex-ratio in different levels' calculated frequencies of CM showed similar in level I, and male prevalence was found in level II and III with statistical significance (p value = 0.022). The male prevalence also revealed in both numerical and structural abnormalities in level II and level III, but no difference in the cases of level I.

CONCLUSION

In conclusion, our observation showed a novel finding of higher male prevalence of CM in level II and III, and both in numerical and structural abnormalities. It's consistent with the theory of better survival in male embryo after partial self-correction of initial chromosomal aberrations, male-specific selection against chromosomal abnormalities.

Risk of Fetal Loss in Pregnancies Undergoing Midtrimester Amniocentesis after Inconclusive Chorionic Villus Sampling

OBJECTIVE

To estimate the procedure-related risk of miscarriage in pregnancies undergoing amniocentesis (AC) following inconclusive results for a chorionic villus sampling (CVS).

METHODS

This was a multicentric retrospective cohort study of patients in which both CVS at 11-13 weeks' gestation and AC at 16-22 weeks were performed between January 1st, 2008, and July 31st, 2017. The primary outcome measure was pregnancy loss prior to 24 weeks gestation; the secondary one was intrauterine demise after 24 weeks.

RESULTS

A total of 287 patients underwent transabdominal CVS and AC. Nine patients were lost at follow-up; therefore, the analysis was conducted on a population of 278 patients (275 singletons and 3 dichorionic twin pregnancies). AC was performed because of placental mosaicism (93.6%), failure of direct/semidirect preparation of trophoblastic cells (3.2%), or targeted genetic testing after the diagnosis of an anomaly in the second trimester (3.2%). In continuing pregnancies, there were no fetal losses prior to 24 weeks' gestation. Two intrauterine demises (including 1 fetus with multiple anomalies and growth restriction) in the third trimester were recorded.

CONCLUSION

Patients undergoing midtrimester AC because of an inconclusive result of CVS can be reasonably reassured that in general the risk of miscarriage and fetal loss following the procedure is very small.

Cervical and Amniotic Fluid Matrix Metalloproteinase-8 and Interleukin-6 Concentrations in Preterm Pregnancies with or without Preterm Premature Rupture of Membranes

INTRODUCTION

Intra-amniotic inflammation is defined by elevated inflammatory biomarkers in the amniotic fluid (AF), either due to microbial invasion of the amniotic cavity (MIAC) or sterile inflammation. Amniocentesis being an invasive procedure, we wanted to investigate whether elevated matrix metalloproteinase-8 (MMP-8) or interleukin-6 (IL-6) concentrations could be detected from cervical fluid samples.

MATERIALS AND METHODS

This prospective study included 67 women with singleton nondiabetic pregnancies with or without preterm premature rupture of membranes (PPROM) between 22+0 and 37+0 weeks of gestation. Simultaneous AF and cervical samples were obtained.

RESULTS

In women without PPROM, cervical MMP-8 concentrations correlated with AF MMP-8 concentrations (rS = 0.466, p = 0.002), but cervical IL-6 did not correlate with AF IL-6 (rS = 0.277, p = 0.076). In PPROM cases no correlations were found. Women with MIAC had higher concentrations of AF MMP-8 and AF IL-6 compared to women without MIAC regardless of membrane status. However, only women without PPROM had higher concentrations of cervical MMP-8 in proven MIAC.

CONCLUSION

In women without PPROM, cervical MMP-8 concentration reflects the magnitude of AF MMP-8, thus potentially guiding the selection of patients benefitting from amniocentesis.

Risk of congenital toxoplasmosis in women with low or indeterminate anti-Toxoplasma IgG avidity index in the first trimester of pregnancy: an observational retrospective study

OBJECTIVES

Congenital toxoplasmosis (CT) affects one to ten fetuses per 10 000 live newborns in western countries. Without knowing pre-conception serostatus, it is hard to date the infection when anti-Toxoplasma IgG and IgM antibodies are positive at first screening. Although a high IgG avidity index (AI) in the first trimester excludes CT, the same cannot be said of intermediate and low AI. The aim of this study was to estimate the risk of CT when intermediate or low AI is detected in the first trimester of pregnancy.

METHODS

Our observational retrospective study enrolled women with positive anti-Toxoplasma IgG and IgM, and low/intermediate AI in the first trimester of gestation seen at two reference centres in northern Italy between 2006 and 2015. All women received spiramycin. When requested by women, a sample of fluid obtained through amniocentesis was tested with a commercial real-time PCR. CT was defined by positive PCR result confirmed on aborted materials or by newborn follow up.

RESULTS

Overall, 778 first-trimester pregnant women were included; AI was low in 532/778 (68%) and intermediate in 246/778 (32%). Amniocenteses were performed in 528/778 (67.9%), with no fetal loss. In all, 19/778 (2.4%) miscarriages and 15/778 (1.9%) pregnancy terminations were recorded; 9/778 (1.6%) were lost to follow up. In two women, PCR on amniotic fluid was positive, but CT was confirmed in only 1/747 cases (0.13%, 95% CI 0.02%-0.75%).

CONCLUSION

In our study, the risk of CT was much lower than anticipated. These data must be considered when counselling these women.

Correlation of Maternal Stress Because of Positive Aneuploidy Screening Serum Analytes and Uterine Arteries' Doppler Ultrasound Index: A Prospective Cohort Study

Background

Antenatal anxiety or maternal stress is a prevalent chronic mental disorder in pregnant women. We have assessed the effect of maternal stress from positive aneuploidy screening results on the changes in uterine artery blood flow.

Materials and Methods

We performed a prospective cohort (one sample) pilot study at a hospital in Tehran, Iran. A total of 60 pregnant women who were candidates for amniocentesis due to abnormal sequential screening test results entered the study. We conducted 2 standard psychological tests, the Spielberger’s State-Trait Anxiety Inventory and the Beck Anxiety Inventory, to determine anxiety levels in the participants before amniocentesis and two weeks after amniocentesis. The uterine artery resistance index was also measured before and two weeks after amniocentesis. The level of maternal stress was compared with the uterine artery resistance index.

Results

Patients had a mean State Trait Anxiety Inventory score before amniocentesis of greater than 40, which meant that the mothers experienced high anxiety. There were no correlations between both inventories’ anxiety scores and uterine artery blood flow before amniocentesis. However, two weeks after amniocentesis, we observed significant negative correlations between the State Anxiety (P=0.0041) and Trait Anxiety (P=0.010) Inventory scores and the uterine artery resistance indexes. Also, there was an association between the decreased right uterine artery resistance index and State Anxiety scores (P=0.036). There were significant correlations between State and Trait Anxiety scores and second trimester analytes of β-human chorionic gonadotropin (β-hCG, P<0.001), α-fetoprotein (P<0.001), and unconjugated estriol (P=0.048).

Conclusion

Maternal anxiety because of positive aneuploidy screening serum analytes and amniocentesis can af- fect perinatal outcomes via mood-based alterations in blood flow of the uterine arteries and the screening markers β-hCG,unconjugated estriol, and α-fetoprotein.

Molecular genetic analysis reveals atypical confined placental mosaicism with a small supernumerary marker chromosome derived from chromosome 18: A clinical report of discordant results from three prenatal tests

We present a case with discordant results in three prenatal screening methods, with additional genetic analyses. Non-invasive prenatal testing (NIPT) was performed on a 41-year-old Japanese woman at 10 weeks of gestation, and the result was positive for trisomy 18 with high accuracy. Amniocentesis was performed at 16 weeks of gestation. However, the result showed 47,XX,+mar[16]/47,XX,+18[2]. Fetal examination by ultrasound revealed no malformations. After termination of the pregnancy, we performed additional genetic analyses, and confirmed the presence of confined placental mosaicism (CPM). Furthermore, a small supernumerary marker chromosome (sSMC) was detected in fetal cells, which was derived de novo from the centromere of chromosome 18. Single nucleotide polymorphism array analysis revealed that fetal chromosome 18 was inherited with maternal uniparental disomy, with a relatively large copy-neutral loss of heterozygosity, including its centromere. Our genetic analyses strongly indicated the cause of result discrepancy in prenatal testing as incomplete trisomy 18 rescue leading to atypical CPM with a sSMC. These findings also offer insight into the mechanisms by which chromosomal aberrations form during human oogenesis and embryogenesis.

Performance of non-invasive prenatal testing for trisomies 21 and 18 in twin pregnancies

Background

Cell-free fetal DNA in maternal plasma represents a source of fetal genetic material that can be sampled noninvasively. There are ample studies confirming the accuracy of NIPT in singleton pregnancies, but there is still relatively little studies demonstrate the feasibility and clinical application of a NIPT for fetal aneuploidy screening in twin pregnancies.

Results

In this study, we have finished 432 twin pregnancies screening by NIPT. There were 4 double chorionic dichorionic diamniotic (DCDA) cases of true positive NIPT results, including 1of T18 and 3 of T21, and 1 monochorionic diamniotic (MCDA) cases of true positive NIPT results, including 1of T21. The combined false-positive frequency for trisomies 21, 18 was 0%. Furthermore, there were 2 cases of false positive NIPT results, including 1 of T7 and 1 of sex chromosome aneuploidy. There was no false negative case, which gave a combined sensitivity and specificity of 100 and 99.53% respectively.

Conclusion

Our study demonstrated NIPT performed well in the detection of trisomy 21 in twin pregnancy. It is feasible and clinical applicable of NIPT for fetal aneuploidy screening in twin pregnancies. But, it needs a large number of clinical samples to demonstrate the applicability of other chromosomal abnormalities besides trisomies 21 and 18 in both singleton pregnancies and twin pregnancies.

Prenatal diagnosis and molecular cytogenetic characterization of low-level mosaicism for tetrasomy 18p at amniocentesis in a pregnancy with a favorable outcome

OBJECTIVE

We present prenatal diagnosis of low-level mosaicism for tetrasomy 18p at amniocentesis in a pregnancy with a favorable outcome.

CASE REPORT

A 40-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a de novo supernumerary isochromosome 18p in eight of 39 colonies of cultured amniocytes. The karyotype was 47,XX,+i(18)(p10)[8]/46,XX[31]. Array comparative genomic hybridization (aCGH) analysis using uncultured amniocytes revealed arr 18p11.32p11.21 [hg 19] (148,963-14,081,887) × 2-3. Repeat amniocentesis was performed at 20 weeks of gestation. Interphase fluorescence in situ hybridization (FISH) analysis showed four 18p11.22-specific probe (RP11-918F20) signals in 11.7% (12/103 cells) of uncultured amniocytes. aCGH analysis on uncultured amniocytes did not detect genomic imbalance in chromosome 18. The parental karyotypes were normal. Polymorphic DNA marker analysis excluded uniparental disomy 18. Cytogenetic analysis of cultured amniocytes at repeat amniocentesis revealed a karyotype of 47,XX,+i(18)(p10)[2]/46,XX[12]. Prenatal ultrasound was unremarkable. The pregnancy was carried to 38 weeks of gestation, and a 2742-g phenotypically normal female baby was delivered with a cord blood karyotype of 46,XX. When examined at 8 months of age, the infant was normal in growth and psychomotor development. Interphase FISH analysis on 21 uncultured urinary cells revealed normal signals in all cells and no mosaic tetrasomy 18p.

CONCLUSION

Low-level mosaic tetrasomy 18p at amniocentesis without ultrasound abnormalities can be associated with a favorable outcome.

Prenatally Diagnosed Rare Trisomy 16 Mosaicism in Human Amniotic Fluid Cells in the Second Trimester: A Case Report

Although trisomy 16 is commonly detected in spontaneous abortions and accounts for over 30% of cases of autosomal trisomy detected after spontaneous abortion, trisomy 16 mosaicism is rarely detected by amniocentesis in the second trimester. Here, we report a case of level III trisomy 16 mosaicism (47,XX,+16[8]/46,XX[31]) diagnosed by cytogenetic analysis of independently cultured amniotic fluid cells. The female baby was delivered at full term with low birth weight and intrauterine growth retardation, and interestingly, her karyotype was normal (46,XX). Given the difficulty in predicting the outcomes of fetuses with this mosaicism, it is recommended to inform the possibility of mosaicisms including this trisomy 16 mosaicism during prenatal genetic diagnosis and genetic counseling for parents.