Impact of high-risk prenatal screening results for 22q11.2 deletion syndrome on obstetric and neonatal management: Secondary analysis from the SMART study

OBJECTIVE

One goal of prenatal genetic screening is to optimize perinatal care and improve infant outcomes. We sought to determine whether high-risk cfDNA screening for 22q11.2 deletion syndrome (22q11.2DS) affected prenatal or neonatal management.

METHODS

This was a secondary analysis from the SMART study. Patients with high-risk cfDNA results for 22q11.2DS were compared with the low-risk cohort for pregnancy characteristics and obstetrical management. To assess differences in neonatal care, we compared high-risk neonates without prenatal genetic confirmation with a 1:1 matched low-risk cohort.

RESULTS

Of 18,020 eligible participants enrolled between 2015 and 2019, 38 (0.21%) were high-risk and 17,982 (99.79%) were low-risk for 22q11.2DS by cfDNA screening. High-risk participants had more prenatal diagnostic testing (55.3%; 21/38 vs. 2.0%; 352/17,982, p < 0.001) and fetal echocardiography (76.9%; 10/13 vs. 19.6%; 10/51, p < 0.001). High-risk newborns without prenatal diagnostic testing had higher rates of neonatal genetic testing (46.2%; 6/13 vs. 0%; 0/51, P < 0.001), echocardiography (30.8%; 4/13 vs. 4.0%; 2/50, p = 0.013), evaluation of calcium levels (46.2%; 6/13 vs. 4.1%; 2/49, P < 0.001) and lymphocyte count (53.8%; 7/13 vs. 15.7%; 8/51, p = 0.008).

CONCLUSIONS

High-risk screening results for 22q11.2DS were associated with higher rates of prenatal and neonatal diagnostic genetic testing and other 22q11.2DS-specific evaluations. However, these interventions were not universally performed, and >50% of high-risk infants were discharged without genetic testing, representing possible missed opportunities to improve outcomes for affected individuals.

Obstetrical, perinatal, and genetic outcomes associated with nonreportable prenatal cell-free DNA screening results

BACKGROUND

The clinical implications of nonreportable cell-free DNA screening results are uncertain, but such results may indicate poor placental implantation in some cases and be associated with adverse obstetrical and perinatal outcomes.

OBJECTIVE

This study aimed to assess the outcomes of pregnancies with nonreportable cell-free DNA screening in a cohort of patients with complete genetic and obstetrical outcomes.

STUDY DESIGN

This was a prespecified secondary analysis of a multicenter prospective observational study of prenatal cell-free DNA screening for fetal aneuploidy and 22q11.2 deletion syndrome. Participants who underwent cell-free DNA screening from April 2015 through January 2019 were offered participation. Obstetrical outcomes and neonatal genetic testing results were collected from 21 primary-care and referral centers in the United States, Europe, and Australia. The primary outcome was risk for adverse obstetrical and perinatal outcomes (aneuploidy, preterm birth at <28, <34, and <37 weeks' gestation, preeclampsia, small for gestational age or birthweight <10th percentile for gestational week, and a composite outcome that included preterm birth at <37 weeks, preeclampsia, small for gestational age, and stillbirth at >20 weeks) after nonreportable cell-free DNA screening because of low fetal fraction or other causes. Multivariable analyses were performed, adjusting for variables known to be associated with obstetrical and perinatal outcomes, nonreportable results, or fetal fraction.

RESULTS

In total, 25,199 pregnant individuals were screened, and 20,194 were enrolled. Genetic confirmation was missing in 1165 (5.8%), 1085 (5.4%) were lost to follow-up, and 93 (0.5%) withdrew; the final study cohort included 17,851 (88.4%) participants who had cell-free DNA, fetal or newborn genetic confirmatory testing, and obstetrical and perinatal outcomes collected. Results were nonreportable in 602 (3.4%) participants. A sample was redrawn and testing attempted again in 427; in 112 (26.2%) participants, results were again nonreportable. Nonreportable results were associated with higher body mass index, chronic hypertension, later gestational age, lower fetal fraction, and Black race. Trisomy 13, 18, or 21 was confirmed in 1.6% with nonreportable tests vs 0.7% with reported results (P=.013). Rates of preterm birth at <28, 34, and 37 weeks, preeclampsia, and the composite outcome were higher among participants with nonreportable results, and further increased among those with a second nonreportable test, whereas the rate of small for gestational age infants was not increased. After adjustment for confounders, the adjusted odds ratios were 2.2 (95% confidence interval, 1.1-4.4) and 2.6 (95% confidence interval, 0.6-10.8) for aneuploidy, and 1.5 (95% confidence interval, 1.2-1.8) and 2.1 (95% confidence interval, 1.4-3.2) for the composite outcome after a first and second nonreportable test, respectively. Of the patients with nonreportable tests, 94.9% had a live birth, as opposed to 98.8% of those with reported test results (adjusted odds ratio for livebirth, 0.20 [95% confidence interval, 0.13-0.30]).

CONCLUSION

Patients with nonreportable cell-free DNA results are at increased risk for a number of adverse outcomes, including aneuploidy, preeclampsia, and preterm birth. They should be offered diagnostic genetic testing, and clinicians should be aware of the increased risk of pregnancy complications.

Performance of prenatal cfDNA screening for sex chromosomes

PURPOSE

To assess the performance of cell-free DNA (cfDNA) screening to detect sex chromosome aneuploidies (SCA) in an unselected obstetrical population with genetic confirmation.

METHODS

This was a planned secondary analysis of the multicenter, prospective SMART study. Patients receiving cfDNA results for autosomal aneuploidies and who had confirmatory genetic results for the relevant sex chromosomal aneuploidies were included. Screening performance for SCAs, including monosomy X (MX) and the sex chromosome trisomies (SCTs; 47,XXX; 47,XXY; 47,XYY) was determined. Fetal sex concordance between cfDNA and genetic screening was also evaluated in euploid pregnancies.

RESULTS

17,538 cases met inclusion criteria. Performance of cfDNA for MX, SCTs and fetal sex was determined in 17,297, 10,333 and 14,486 pregnancies, respectively. Sensitivity, specificity, and PPV of cfDNA were 83.3%, 99.9%, and 22.7% for MX, and 70.4%, 99.9%, and 82.6% for the combined SCTs. The accuracy of fetal sex prediction by cfDNA was 100%.

CONCLUSION

Screening performance of cfDNA for SCAs is comparable to that reported in other studies. The PPV for the SCTs was similar to the autosomal trisomies, while the PPV for MX was substantially lower. No discordance in fetal sex was observed between cfDNA and postnatal genetic screening in euploid pregnancies. These data will assist interpretation and counseling for cfDNA results for sex chromosomes.

A retrospective cohort study of the characteristics of unsuccessful operative vaginal deliveries

INTRODUCTION

Unsuccessful operative vaginal delivery (OVD) is associated with high rates of materno-fetal morbidity. We aimed to examine institutional rates of unsuccessful OVDs (uOVD) and compare them with successful OVD (sOVD) in order to identify factors to aid patient selection and education.

METHODS

A 6-month retrospective cohort study was performed on all unsuccessful and successful OVDs in a tertiary level maternity hospital in the Republic of Ireland. Maternal demographics and obstetric factors were assessed to evaluate potential underlying risk factors for unsuccessful operative vaginal delivery versus successful vaginal delivery.

RESULTS

There were 4,191 births during the study period with an OVD rate of 14.2% (n = 595) with 28 (4.7% of OVDs) being unsuccessful. Unsuccessful OVD were predominately nulliparous (25; 89.2%) with a mean maternal age of 30.1 years (range 20-42), with more than half (n = 15, 53.5%) being induced. The most common indication for induction was prolonged rupture of membranes (PROM) (n = 7, 25%) which was significantly different from the successful OVD group. A senior obstetrician was significantly more likely to be the primary operator in uOVD when compared to sOVD. (82.1 % V 54.1% p < 0.01). The majority of unsuccessful OVD were vacuum deliveries (n = 17; 60.7%), with a significantly higher mean birthweight when compared to successful OVD (3.695 kg V 3.483 kg; p < 0.01). Following an unsuccessful OVD, women were more likely to have a postpartum haemorrhage (64.2 % V 31.5% p < 0.01) and their infant was more likely to require admission to the neonatal intensive care unit (NICU) (32.1 % V 5.8% p < 0.01) when compared with successful OVD.

CONCLUSION

Risk factors for unsuccessful OVD were higher birth weight and induction of labour. There was a higher incidence of postpartum haemorrhage and NICU admission when compared with successful OVD.

Dynamic growth changes in fetal growth restriction using serial ultrasonographic biometry and umbilical artery doppler: The multicenter PORTO study

OBJECTIVE

To describe the growth dynamics of fetuses with initial fetal growth restriction (FGR) later outgrowing the 10th centile for estimated fetal weight with respect to perinatal outcomes and maternal factors.

METHODS

A multicenter prospective study recruited 1116 patients for ultrasound surveillance between 2010 and 2012. All pregnancies were growth-restricted singleton gestations between 24 + 0 and 36 + 0 weeks. Biometry and Doppler analysis were carried out, and delivery and adverse perinatal outcomes were recorded.

RESULTS

A total of 193 (17%) fetuses outgrew their diagnosis of initial FGR (surpassed the 10th centile) on their last sonogram before delivery. These fetuses were termed "growers," to compare with the true FGR group. The mothers of "growers" were less likely to be smokers (14% vs 25%, P = 0.0001) or affected by hypertensive pregnancy complications (5.2% vs 15%, P = 0.001). Of the growers, 49 (25%) had an abnormal umbilical artery Doppler; however, in most cases (33/49, 67%), this was a single episode of raised umbilical artery pulsatility index, which subsequently normalized.

CONCLUSION

There were dynamic growth changes in FGR fetuses, with 17% outgrowing their original diagnosis. Positive growth spurts more commonly occurred in healthy mothers. Once a fetus had outgrown the 10th centile, antenatal surveillance could be decreased.

A randomised open-label trial to assess outpatient induction of labour (HOMEIND) and compare efficacy of Propess vs Dilapan-S® for induction of labour at 39 weeks' gestation in normal risk nulliparous women: study protocol for a randomised controlled trial

BACKGROUND

Induction of labour (IOL) at 39 weeks has been shown to decrease maternal and neonatal adverse outcomes. Given the growing demand for 39-week IOL, it is imperative that effective methods be assessed for induction in the outpatient setting. The aim of this study is to answer the clinical question as to whether Dilapan-S® vs Propess® as a method of cervical ripening is non-inferior in the outpatient setting at 39 weeks and to ascertain whether Dilapan-S® 12 h is non-inferior to Dilapan-S® 24 h.

METHODS

This study is an open-label parallel group single-centre randomised trial. Participants are normal risk nulliparous women who have no pregnancy-related or medical contraindication to IOL. Women will be randomised to one of three induction groups-Dilapan-S® (12-h insertion or 24-h insertion) or Propess. Induction will be initiated between 39+0 and 39+4 weeks' gestation and participants will return home for either 12 or 24 h. They will be readmitted 12/24 h later in order to continue with induction of labour. Patient recruitment will take place over 30 months within a single centre. The study will recruit a maximum 109 women for each study arm. Total duration of participants' involvement in the trial will be 8 weeks to allow for postpartum follow-up.

DISCUSSION

This study will definitively answer whether Dilapan-S is non-inferior to Propess® as a method of induction of labour in the outpatient setting and whether cervical ripening with Dilapan-S over a 12-h timeframe is non-inferior to cervical ripening with Dilapan-S over a 24-h timeframe.

TRIAL REGISTRATION

EudraCT Number 2019-004697-25 Registered 14 September 2020.

Formation of robust bound states of interacting microwave photons

Systems of correlated particles appear in many fields of modern science and represent some of the most intractable computational problems in nature. The computational challenge in these systems arises when interactions become comparable to other energy scales, which makes the state of each particle depend on all other particles1. The lack of general solutions for the three-body problem and acceptable theory for strongly correlated electrons shows that our understanding of correlated systems fades when the particle number or the interaction strength increases. One of the hallmarks of interacting systems is the formation of multiparticle bound states2-9. Here we develop a high-fidelity parameterizable fSim gate and implement the periodic quantum circuit of the spin-½ XXZ model in a ring of 24 superconducting qubits. We study the propagation of these excitations and observe their bound nature for up to five photons. We devise a phase-sensitive method for constructing the few-body spectrum of the bound states and extract their pseudo-charge by introducing a synthetic flux. By introducing interactions between the ring and additional qubits, we observe an unexpected resilience of the bound states to integrability breaking. This finding goes against the idea that bound states in non-integrable systems are unstable when their energies overlap with the continuum spectrum. Our work provides experimental evidence for bound states of interacting photons and discovers their stability beyond the integrability limit.

Obstetric Rectal Buttonhole Tears: A Case Series and Literature review

INTRODUCTION

Isolated rectal buttonhole tears are a rare obstetric complication and so there is a lack of consensus for their management. This case series reviews the published literature on obstetric rectal buttonhole injuries and provides further cases from our institution.

METHODS

A literature review was carried out. All results were reviewed. Rectal buttonhole tears following vaginal delivery between 2012 and May 2022 in our institution were identified. Repair technique and post-operative management were recorded.

RESULTS

There were 14 published case reports. Seven case reports described a two-layer closure, and seven reports described a three-layer closure. Four cases were repaired in collaboration with colorectal surgeons. Twelve cases were asymptomatic after six weeks. One woman had a defunctioning stoma following a wound breakdown and one woman was readmitted with a rectal haemorrhage. We identified two women in our institution with buttonhole tears. Three-layer repairs were performed in both cases and each woman made an uneventful recovery.

CONCLUSION

Repair techniques of rectal buttonhole tears vary among institutions. Despite this variance, most women suffer no short-term morbidity following these injuries. This review adds to the current literature with examples of different repair techniques and outcomes.

Cell-free DNA screening for trisomies 21, 18, and 13 in pregnancies at low and high risk for aneuploidy with genetic confirmation

BACKGROUND

Cell-free DNA noninvasive prenatal screening for trisomies 21, 18, and 13 has been rapidly adopted into clinical practice. However, previous studies are limited by a lack of follow-up genetic testing to confirm the outcomes and accurately assess test performance, particularly in women at a low risk for aneuploidy.

OBJECTIVE

To measure and compare the performance of cell-free DNA screening for trisomies 21, 18, and 13 between women at a low and high risk for aneuploidy in a large, prospective cohort with genetic confirmation of results STUDY DESIGN: This was a multicenter prospective observational study at 21 centers in 6 countries. Women who had single-nucleotide-polymorphism-based cell-free DNA screening for trisomies 21, 18, and 13 were enrolled. Genetic confirmation was obtained from prenatal or newborn DNA samples. The test performance and test failure (no-call) rates were assessed for the cohort, and women with low and high previous risks for aneuploidy were compared. An updated cell-free DNA algorithm blinded to the pregnancy outcome was also assessed.

RESULTS

A total of 20,194 women were enrolled at a median gestational age of 12.6 weeks (interquartile range, 11.6-13.9). The genetic outcomes were confirmed in 17,851 cases (88.4%): 13,043 (73.1%) low-risk and 4808 (26.9%) high-risk cases for aneuploidy. Overall, 133 trisomies were diagnosed (100 trisomy 21; 18 trisomy 18; 15 trisomy 13). The cell-free DNA screen positive rate was lower in the low-risk vs the high-risk group (0.27% vs 2.2%; P<.0001). The sensitivity and specificity were similar between the groups. The positive predictive value for the low- and high-risk groups was 85.7% vs 97.5%; P=.058 for trisomy 21; 50.0% vs 81.3%; P=.283 for trisomy 18; and 62.5% vs 83.3; P=.58 for trisomy 13, respectively. Overall, 602 (3.4%) patients had no-call result after the first draw and 287 (1.61%) after including cases with a second draw. The trisomy rate was higher in the 287 cases with no-call results than patients with a result on a first draw (2.8% vs 0.7%; P=.001). The updated algorithm showed similar sensitivity and specificity to the study algorithm with a lower no-call rate.

CONCLUSION

In women at a low risk for aneuploidy, single-nucleotide-polymorphism-based cell-free DNA has high sensitivity and specificity, positive predictive value of 85.7% for trisomy 21 and 74.3% for the 3 common trisomies. Patients who receive a no-call result are at an increased risk of aneuploidy and require additional investigation.

Cell-free DNA screening for prenatal detection of 22q11.2 deletion syndrome

BACKGROUND

Historically, prenatal screening has focused primarily on the detection of fetal aneuploidies. Cell-free DNA now enables noninvasive screening for subchromosomal copy number variants, including 22q11.2 deletion syndrome (or DiGeorge syndrome), which is the most common microdeletion and a leading cause of congenital heart defects and neurodevelopmental delay. Although smaller studies have demonstrated the feasibility of screening for 22q11.2 deletion syndrome, large cohort studies with confirmatory postnatal testing to assess test performance have not been reported.

OBJECTIVE

This study aimed to assess the performance of single-nucleotide polymorphism-based, prenatal cell-free DNA screening for detection of 22q11.2 deletion syndrome.

STUDY DESIGN

Patients who underwent single-nucleotide polymorphism-based prenatal cell-free DNA screening for 22q11.2 deletion syndrome were prospectively enrolled at 21 centers in 6 countries. Prenatal or newborn DNA samples were requested in all cases for genetic confirmation using chromosomal microarrays. The primary outcome was sensitivity, specificity, positive predictive value, and negative predictive value of cell-free DNA screening for the detection of all deletions, including the classical deletion and nested deletions that are ≥500 kb, in the 22q11.2 low-copy repeat A-D region. Secondary outcomes included the prevalence of 22q11.2 deletion syndrome and performance of an updated cell-free DNA algorithm that was evaluated with blinding to the pregnancy outcome.

RESULTS

Of the 20,887 women enrolled, a genetic outcome was available for 18,289 (87.6%). A total of 12 22q11.2 deletion syndrome cases were confirmed in the cohort, including 5 (41.7%) nested deletions, yielding a prevalence of 1 in 1524. In the total cohort, cell-free DNA screening identified 17,976 (98.3%) cases as low risk for 22q11.2 deletion syndrome and 38 (0.2%) cases as high risk; 275 (1.5%) cases were nonreportable. Overall, 9 of 12 cases of 22q11.2 were detected, yielding a sensitivity of 75.0% (95% confidence interval, 42.8-94.5); specificity of 99.84% (95% confidence interval, 99.77-99.89); positive predictive value of 23.7% (95% confidence interval, 11.44-40.24), and negative predictive value of 99.98% (95% confidence interval, 99.95-100). None of the cases with a nonreportable result was diagnosed with 22q11.2 deletion syndrome. The updated algorithm detected 10 of 12 cases (83.3%; 95% confidence interval, 51.6-97.9) with a lower false positive rate (0.05% vs 0.16%; P<.001) and a positive predictive value of 52.6% (10/19; 95% confidence interval, 28.9-75.6).

CONCLUSION

Noninvasive cell-free DNA prenatal screening for 22q11.2 deletion syndrome can detect most affected cases, including smaller nested deletions, with a low false positive rate.

Euploid First-Trimester Cystic Hygroma: A More Benign Entity than Previously Thought?

OBJECTIVE

Studies summarizing the outcome of first-trimester septated cystic hygroma are generally based on small studies or from multiple centers with limited ascertainment. We reviewed the natural history of a large cohort of such cases from a single tertiary referral center, with the aim being to establish contemporary outcome data, particularly in the setting of normal karyotype.

METHODS

A retrospective cohort study from 2007 to 2017 was conducted at a single tertiary referral prenatal diagnosis center. Data were analyzed from a prospectively collated fetal anomaly database. Search terms were "increased nuchal translucency (NT)," "cystic hygroma," and "septated cystic hygroma." All cases were confirmed to have NT >3 mm with septations. Cases of simple increased NT without septations were excluded.

RESULTS

During the study period, over 110,000 pregnancies were delivered at our center, resulting in 410 cases of septated cystic hygroma diagnosed prior to 14 weeks' gestation. Pregnancy outcome was obtained in 99% (405/410) of cases, with detailed pathology outcome available in 92% (378/410). A total of 87% (351/405) underwent invasive prenatal testing, and postnatal chromosome status was established in further 27 cases. A total of 61% (230/378) had abnormal chromosomal status. Of the 39% (148/378) with normal chromosomal status, only 13% (19/148) had a significant structural fetal abnormality, which included 7 cardiac and 12 noncardiac abnormalities. Overall, the perinatal loss was 62% (253/405). The total survival rate in the setting of euploid cystic hygroma without structural abnormality was 84% (108/129).

CONCLUSIONS

Counseling regarding outcomes in the setting of first-trimester septated cystic hygroma initially focuses on the strong likelihood of an abnormal karyotype, which occurs in 61% of cases. However, once fetal chromosomal abnormality is excluded, our results demonstrate only a 13% incidence of major structural fetal abnormality, which appears significantly less than previously reported. Normal fetuses have a 77% survival rate. These data represent the largest single-center study of first-trimester cystic hygroma with complete outcome data and therefore will be useful for contemporary patient counseling. Such counseling can be more positive than previously expected, once chromosomal abnormality is first excluded.

Immunological assessment of SARS-CoV-2 infection in pregnancy from diagnosis to delivery: A multicentre prospective study

BACKGROUND

Background Population-based data on SARS-CoV-2 infection in pregnancy and assessment of passive immunity to the neonate, is lacking. We profiled the maternal and fetal response using a combination of viral RNA from naso-pharyngeal swabs and serological assessment of antibodies against SARS-CoV-2.

METHODS

This multicentre prospective observational study was conducted between March 24th and August 31st 2020. Two independent cohorts were established, a symptomatic SARS-CoV-2 cohort and a cohort of asymptomatic pregnant women attending two of the largest maternity hospitals in Europe. Symptomatic women were invited to provide a serum sample to assess antibody responses. Asymptomatic pregnant women provided a nasopharyngeal swab and serum sample. RT-PCR for viral RNA was performed using the Cobas SARS-CoV-2 6800 platform (Roche). Umbilical cord bloods were obtained at delivery. Maternal and fetal serological response was measured using both the Elecsys® Anti-SARS-CoV-2 immunoassay (Roche), Abbott SARS-CoV-2 IgG Assay and the IgM Architect assay. Informed written consent was obtained from all participants.

RESULTS

Ten of twenty three symptomatic women had SARS-CoV-2 RNA detected on nasopharyngeal swabs. Five (5/23, 21.7%) demonstrated serological evidence of anti-SARS-CoV-2 IgG antibodies and seven (30.4%, 7/23) were positive for IgM antibodies. In the asymptomatic cohort, the prevalence of SARS-CoV-2 infection in RNA was 0.16% (1/608). IgG SARS-CoV-2 antibodies were detected in 1·67% (10/598, 95% CI 0·8%-3·1%) and IgM in 3·51% (21/598, 95% CI 2·3-5·5%). Nine women had repeat testing post the baseline test. Four (4/9, 44%) remained IgM positive and one remained IgG positive. 3 IgG anti-SARS-CoV-2 antibodies were detectable in cord bloods from babies born to five seropositive women who delivered during the study. The mean gestation at serological test was 34 weeks. The mean time between maternal serologic positivity and detection in umbilical cord samples was 28 days.

CONCLUSION

Using two independent serological assays, we present a comprehensive illustration of the antibody response to SARS-CoV-2 in pregnancy, and show a low prevalence of asymptomatic SARS-CoV2. Transplacental migration of anti-SARS-CoV-2 antibodies was identified in cord blood of women who demonstrated antenatal anti-SARS-CoV-2 antibodies, raising the possibility of passive immunity.

Correlation of maternal body mass index with umbilical artery Doppler in pregnancies complicated by fetal growth restriction and associated outcomes

OBJECTIVE

To evaluate the correlation between umbilical artery (UA) Doppler and its feasibility across categories of maternal body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) in the presence of fetal growth restriction (FGR).

METHODS

A total of 1074 singleton pregnancies with suspected FGR on ultrasound examination between 24⁺⁰ and 36⁺⁰ weeks of pregnancy were reviewed. Evaluation of the UA Doppler was performed at 1- to 2-weekly intervals. Abnormal UA Doppler findings and delivery outcomes were compared between the different maternal BMI categories.

RESULTS

Increased UA pulsatility index (PI >95th centile) was reported in 81% of obese class II patients (BMI 35-39.9) compared with a 46% incidence in the remaining categories, normal (BMI <24.9), overweight (BMI 25-29.9), and obese class I (BMI 30-34.9) (P = 0.001). In absent or reversed end diastolic flow (AEDF/REDF) we found an increasing incidence across the BMI categories (4%-25%) (P < 0.001). Higher maternal BMI was associated with lower birthweights and higher cesarean section rates. Increasing maternal BMI did not affect successful assessment of UA Doppler.

CONCLUSION

There is a positive correlation between increasing maternal BMI and abnormal UA Doppler findings in FGR. Maternal BMI may be considered as an additional risk factor when evaluating UA Doppler for placental insufficiency.

Embolus Analog Trajectory Paths Under Physiological Flowrates Through Patient-Specific Aortic Arch Models

Atrial fibrillation (AF) is the most common irregular heartbeat among the world's population and is a major contributor to cardiogenic embolisms and acute ischemic stroke (AIS). However, the role AF flow plays in the trajectory paths of cardiogenic emboli has not been experimentally investigated. A physiological simulation system was designed to analyze the trajectory patterns of bovine embolus analogs (EAs) (n = 720) through four patient-specific models, under three flow conditions: steady flow, normal pulsatile flow, and AF pulsatile flow. It was seen that EA trajectory paths were proportional to the percentage flowrate split of 25–31% along the branching vessels. Overall, AF flow conditions increased trajectories through the left- (LCCA) and right (RCCA)-common carotid artery by 25% with respect to normal pulsatile flow. There was no statistical difference in the distribution of clot trajectories when the clot was released from the right, left, or anterior positions. Significantly, more EAs traveled through the brachiocephalic trunk (BCT) than through the LCCA or the left subclavian. Yet of the EAs that traveled through the common carotid arteries, there was a greater affiliation toward the LCCA compared to the RCCA (p < 0.05).

Early onset preeclampsia is associated with an elevated mean platelet volume (MPV) and a greater rise in MPV from time of booking compared with pregnant controls: results of the CAPE study

OBJECTIVE

To characterise Mean platelet volume (MPV) in patients with early onset preeclampsia (EOPE) and unaffected controls from time of first antenatal visit until the postpartum.

MATERIALS AND METHODS

Retrospective secondary analysis of an observational study in an Irish tertiary referral centre with 9000 deliveries annually. The MPV of 27 women with EOPE was compared to 19 unaffected controls. The inclusion criteria for the disease state was the development of EOPE defined by the National Institute for Health and Care Excellence (NICE) guideline, as new onset hypertension presenting after 20 weeks and prior to 34 weeks with significant proteinuria. Between October 2013 and July 2015 we recruited 27 women with EOPE and 19 pregnant controls. Statistical analysis was performed using paired T-test of Mann-Whitney test where appropriate and a P-value <0.05 was deemed significant.

RESULTS

At time of diagnosis and late in the third trimester MPV was significantly increased to 9.0 (±0.3) fL in cases of EOPE in comparison to 8.5 (±0.6) fL in normotensive controls (P<0.05). There was no significant difference during the first trimester or postpartum when comparing the MPV in EOPE to controls.

CONCLUSION

Despite an increased MPV at time of diagnosis of EOPE this study did not demonstrate a potential use for increased MPV as a first trimester screening tool.

Elevated plasma TFPI activity causes attenuated TF-dependent thrombin generation in early onset preeclampsia

Early onset preeclampsia (EOP) is a pregnancy-specific proinflammatory disorder that is characterised by competing thrombotic and bleeding risks. It was the aim of this study to characterise thrombin generation, a major determinant of thrombotic and bleeding risk, in order to better understand the haemostatic balance in patients with EOP. Patients with EOP were recruited at the Rotunda Hospital, Dublin. Twenty-six cases of EOP were recruited over a 21-month period, out of 15,299 deliveries at the Rotunda. Blood samples were collected into sodium citrate plus corn trypsin inhibitor anticoagulated vacutainers, platelet-poor plasma was prepared, and calibrated automated thrombography was used to assess thrombin generation. Results were compared to age and sex-matched non-pregnant controls (n=13) and age-and gestation-matched pregnant controls (n=20). The rate and extent of thrombin generation triggered by low-dose tissue factor (TF) was significantly reduced in patients with EOP compared to pregnant controls, most significantly in cases of severe EOP. EOP patients displayed a trend towards an increased response to endogenous activated protein C and thrombomodulin relative to pregnant controls. Plasma tissue factor pathway inhibitor (TFPI) activity was increased in EOP patients. Inhibition of TFPI abolished the attenuation of thrombin generation stimulated by low-dose TF. In conclusion, patients with EOP are characterised by an attenuated coagulation response characterised by reduced thrombin generation stimulated by low-dose TF and elevated plasma TFPI activity. These changes in coagulation may modulate thrombotic risk and bleeding risk in patients with EOP.

Left ventricular rotational mechanics in infants with hypoxic ischemic encephalopathy and preterm infants at 36 weeks postmenstrual age: A comparison with healthy term controls

BACKGROUND AND AIMS

There is a paucity of data on left ventricle (LV) rotational physiology in neonates. We aimed to assess rotational mechanics in infants with hypoxic ischemic encephalopathy (HIE) and premature infants (<32 weeks) at 36 weeks postmenstrual age (PMA) (preterm group) and compare them with healthy term controls (term controls). We also compared the parameters in preterm infants with and without chronic lung disease (CLD).

METHODS

Echocardiography was performed within 48 hours of birth or at 36 weeks PMA. LV basal and apical rotation, twist (and torsion=twist/LV length), twist rate (LVTR), and untwist rate (LVUTR) were measured. One-way ANOVA was used to compare values.

RESULTS

There was no difference in gestation (40.0 [39.1-40.3] vs 39.9 [39.0-40.9], P>.05) or birthweight (3.7 [3.4-4.1] vs 3.5 [3.2-3.9], P>.05) between the HIE group (n=16) and term controls (n=30). The preterm group (n=35) had a gestation and weight of 36.0 [34.6-36.3] weeks and 2.3 [2.0-2.4] kg. The HIE group had lower twist, torsion, LVTR, and LVUTR than the other two groups. The preterm group had a more negative (clockwise) basal rotation while the term group had a more positive (counterclockwise) apical rotation. Preterm infants with CLD had higher apical rotation, twist, and torsion when compared to infants without CLD.

CONCLUSION

Infants with HIE have reduced rotational mechanics. Preterm infants at 36 weeks PMA have comparable measurements of twist to term infants. This is achieved by predominant basal rather than apical rotation. Infants with CLD have increased apical rotation.

Postnatal MRI Brain in Infants Treated for Twin-Twin Transfusion Syndrome

Untreated twin-twin transfusion syndrome (TTTS) is associated with significant mortality and neurological impairment. Fetoscopic laser surgery (FLS) is the treatment of choice. We sought to assess intracranial abnormalities in TTTS twins following treatment. In this prospective, blinded study MRI scans were performed on 3 groups; (1) monochorionic diamniotic (MCDA) twins with TTTS who had undergone FLS (n = 10), (2) MCDA twins without TTTS (n = 8) and (3) dichorionic twins (n = 8). Scans were scored as either normal or abnormal. The primary outcome was a composite of abnormal MRI brain or intrauterine fetal demise. The primary outcome occurred in 6/10 (60%) of the TTTS group versus 3/8 (37.5%) in the MCDA group. The primary outcome was significantly different across all study groups [p = 0.029; X2 = 7.112]. We found that twins treated for TTTS are more likely to have abnormalities on MRI brain at term than other twin groups. This group merits term-corrected MRI as part of their postnatal assessment.

Effect of magnesium sulfate administration for neuroprotection on latency in women with preterm premature rupture of membranes

OBJECTIVE

This study aims to evaluate whether magnesium sulfate administration for neuroprotection prolongs latency in women with preterm premature rupture of membranes (PPROM) between 24 and 31(6/7) weeks' gestation.

STUDY DESIGN

This is a secondary analysis of a randomized controlled trial of magnesium sulfate for prevention of cerebral palsy. Gravid women with a singleton pregnancy between 24 and 31(6/7) weeks' gestation with PPROM without evidence of labor were randomized to receive magnesium sulfate, administered intravenously as a 6-g bolus followed by a constant infusion of 2 g per hour up to 12 hours, or placebo. Maternal outcomes for this analysis were delivery in less than 48 hours and in less than 7 days from randomization. Neonatal outcomes included a composite of respiratory distress syndrome, interventricular hemorrhage grades 3 or 4, periventricular leukomalacia, sepsis, necrotizing enterocolitis, retinopathy of prematurity, or death.

RESULTS

A total of 1,259 women were included. The rate of delivery < 48 hours was not different in the magnesium sulfate and the placebo groups (22.2 and 20.7%, p = 0.51). Delivery < 7 days was similar between groups (55.4 and 51.4%, p = 0.16). Median latency was also similar between groups (median [interquartile range], 6.0 days [range, 2.4-13.8 days] and 6.6 days [range, 2.4-15.1 days], p = 0.29). Composite neonatal outcomes did not differ between groups.

CONCLUSION

Magnesium sulfate administration given for neuroprotection in women with a singleton gestation with PPROM and without labor before 32 weeks does not impact latency.

The association of cord serum cytokines with neurodevelopmental outcomes

OBJECTIVE

To test whether elevated umbilical cord serum inflammatory cytokine levels predicted subsequent cerebral palsy (CP) or neurodevelopmental delay (NDD).

STUDY DESIGN

Nested case-control analysis within a clinical trial of antenatal magnesium sulfate (MgSO4) before anticipated preterm birth (PTB) for prevention of CP, with evaluation of surviving children at the age of 2. NDD was defined as a Bayley psychomotor developmental index (PDI) and/or mental developmental index (MDI) < 70. Controls, defined as surviving children without CP and with Bayley PDI and MDI ≥ 85, were matched by race and gestational age. Cord serum was analyzed for interleukin-8 (IL-8) interleukin-1 beta (IL-1β), and tumor necrosis factor-α (TNF-α) levels. Elevated cytokine levels were defined as ≥ 75th percentile in placebo-exposed controls. Analyses compared case/control cytokine levels, adjusting for MgSO4 exposure, gestational age, race/ethnicity, and sociodemographic differences.

RESULTS

Logistic regression analysis with 339 cases and 276 controls showed that elevated IL-8 and IL-1β were more common in cord blood serum from infants with subsequent low MDI as compared with controls. After adjusting for additional confounders, the significant differences were no longer evident. Cytokine levels (IL-8, IL-1β, and TNF-α) were not elevated with CP or low PDI.

CONCLUSION

Cord serum IL-8, IL-1β, and TNF-α levels in preterm infants are not associated with subsequent CP or NDD.

Length of latency with preterm premature rupture of membranes before 32 weeks' gestation

OBJECTIVE

The objective of the article is to describe latency for patients with preterm premature membrane rupture (PPROM) between 24(0/7) and 31(6/7) weeks' gestation.

STUDY DESIGN

Secondary analysis of data collected prospectively in a multicenter clinical trial of magnesium sulfate for cerebral palsy prevention. Women with PPROM and fewer than six contractions per hour at enrollment who were candidates for expectant management (n = 1,377) were included in this analysis. Length of latency was calculated in days by subtracting the time of delivery from the time of membrane rupture.

RESULTS

At each week of gestation, median latency between 24 and 28 weeks was similar at approximately 9 days, but it was significantly shorter with PPROM at 29, 30, and 31 weeks (p < 0.001). In addition, the percentage of patients remaining undelivered at 7 days and 14 days was similar for PPROM between 24 and 28 weeks, but it decreased significantly after that. For each gestational age, the proportion of patients remaining pregnant declined in a fashion similar to an exponential pattern.

CONCLUSION

Median latency after PPROM is similar from 24 to 28 weeks' gestation, but it shortens with PPROM at and after 29 weeks.

Umbilical and fetal middle cerebral artery Doppler reference ranges in a twin population followed longitudinally from 24 to 38 weeks' gestation

OBJECTIVE

To construct monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin reference ranges for umbilical artery (UA) pulsatility index (PI), UA resistance index (RI), fetal middle cerebral artery (MCA) PI and peak systolic velocity (PSV) and cerebroplacental ratio (CPR) from 24 weeks' to 38 weeks' gestation and compare these with published normal values for singleton pregnancies.

METHODS

This prospective multicenter cohort study included 1028 unselected twin pairs recruited over a 2-year period. Participants with dichorionic twins underwent fortnightly ultrasound surveillance from 24 weeks' gestation, with monochorionic twins being followed every 2 weeks from 16 weeks until delivery. A total of 7536 fetal Doppler examinations in 618 twin pregnancies were included in the analysis, with reference ranges for MCDA and DCDA pregnancies constructed for each of the Doppler indices using multilevel modeling.

RESULTS

UA-PI and UA-RI appear to be higher in twins than in singletons, and MCA-PI and MCA-PSV appear to be lower. The CPR also appears to be lower in twins than in singletons. Similar MCA indices were observed in MCDA and DCDA twins.

CONCLUSION

We have established longitudinal reference ranges for UA-PI and UA-RI, MCA-PI and MCA-PSV and CPR in twin pregnancies, which appear to differ from those in singleton pregnancies. The derived twin-specific reference ranges may be more appropriate in the surveillance of these high-risk pregnancies. Applying the singleton CPR cut-off of ≤ 1.0 may lead to a large number of false-positive diagnoses of cerebral redistribution in twin fetuses.