Multisite assessment of the impact of a prenatal testing educational App on patient knowledge and preparedness for prenatal testing decision making.

In this study, we wanted to assess the impact of the use of a patient educational app on patient knowledge about noninvasive prenatal testing (NIPT) and preparedness for prenatal screening decision-making. A randomized control study was carried out at three international sites between January 2019 and October 2020. Study participants completed a pre-consultation survey and post-consultation survey to assess knowledge, satisfaction, and preparedness for prenatal screening consultation. Providers completed a post-consultation survey. In the control arm, the pre-consultation survey was completed prior to consultation with their prenatal care provider. In the intervention arm, the pre-consultation survey was completed after using the app but prior to consultation with their prenatal care provider. Mean knowledge scores in the 203 participants using the app were significantly higher pre-consultation (p < 0.001) and post-consultation (p < 0.005) than those not using the app. Higher pre-consultation knowledge scores in the intervention group were observed at all sites. Most (86%) app users stated they were "Satisfied" or "Very Satisfied" with it as a tool. Providers rated the intervention group as more prepared than controls (p = 0.027); provider assessment of knowledge was not significantly different (p = 0.073). This study shows that clinical implementation of a patient educational app in a real-world setting was feasible, acceptable to pregnant people, and positively impacted patient knowledge.

Noninvasive Detection of Fetal Aneuploidy Using Next Generation Sequencing.

Cell-free DNA (cfDNA)-based noninvasive prenatal testing (NIPT) utilizing next generation sequencing (NGS) is a highly sensitive and specific approach designed to screen for fetal aneuploidy. NIPT was first introduced in 2011 and has been rapidly adopted in a clinical setting because of the improved performance afforded compared with traditional prenatal serum screening options. We describe a PCR-free, paired-end sequencing-based NIPT, the VeriSeq NIPT Solution. This NIPT screens for fetal aneuploidy of chromosomes 21, 18, 13, X, and Y. Using the validated approach detailed here, users can achieve high sensitivities and specificities for trisomies 21, 18, and 13 as well as sex chromosome aneuploidies with low failure rates. The automated workflow can be completed in 1 day, with only 2 h of hands-on time from a single technician.

Fetal aneuploidy screening with cell-free DNA in late gestation.

OBJECTIVE: The aim of this study was to evaluate clinical use of NIPT at gestational ages of 23 weeks and above. METHODS: A cohort of 5579 clinical patients with singleton gestations of 23 weeks or greater submitting a blood sample for NIPT in an 18-month period were selected for this study. Clinical outcomes were requested for samples with NIPT results indicating fetal aneuploidy and compared with NIPT findings to confirm concordance or discordance. RESULTS: A review of clinical indications revealed that a significantly (p < 0.0001) larger proportion of late-gestation samples indicated abnormal ultrasound findings with or without other indications, 6.2% and 42.1%, compared with early-gestation samples, 1.8% and 6.0%, respectively. Of 5372 reported late-gestation samples, 151 (2.8%) were reported as aneuploidy detected or suspected. In late-gestation samples, the overall observed positive predictive value (PPV) for NIPT was 64.7%, with an observed PPV of 100% in the subset of cases with multiple clinical indications including abnormal ultrasound findings. CONCLUSIONS: NIPT is a highly accurate prenatal screening option for women after 23 weeks of gestation. Women who presented for NIPT in the latter stages of pregnancy more frequently specified clinical indications of abnormal ultrasound findings than women who entered screening earlier in pregnancy.

Incidence of X and Y Chromosomal Aneuploidy in a Large Child Bearing Population.

BACKGROUND: X&Y chromosomal aneuploidies are among the most common human whole-chromosomal copy number changes, but the population-based incidence and prevalence in the child-bearing population is unclear. METHODS: This retrospective analysis of prospectively collected data leveraged a routine non-invasive prenatal test (NIPT) using parental genotyping to estimate the population-based incidence of X&Y chromosome variations in this population referred for NIPT (generally due to advanced maternal age). RESULTS: From 141,916 women and 29,336 men, 119 X&Y chromosomal abnormalities (prevalence: 1 in 1,439) were identified. Maternal findings include: 43 cases of 45,X (40 mosaic); 30 cases of 47,XXX (12 mosaic); 3 cases of 46,XX uniparental disomy; 2 cases of 46,XY/46,XX; 23 cases of mosaicism of unknown type; 2 cases of 47,XX,i(X)(q10). Paternal findings include: 2 cases of 47,XXY (1 mosaic); 10 cases of 47,XYY (1 mosaic); 4 partial Y deletions. CONCLUSIONS: Single chromosome aneuploidy was present in one of every 1,439 individuals considered in this study, showing 47,XXX; 47,XX,i(X)(q10); 47,XYY; 47,XXY, partial Y deletions, and a high level of mosaicism for 45,X. This expands significantly our understanding of X&Y chromosomal variations and fertility issues, and is critical for families and adults affected by these disorders. This current and extensive information on fertility will be beneficial for genetic counseling on prenatal diagnoses as well as for newly diagnosed postnatal cases.

Growth and differentiation factor 9 promotes oocyte growth at the primary but not the early secondary stage in three-dimensional follicle culture.

PURPOSE: Factors that differentially regulate oocyte and granulosa cell growth within the early preantral follicle and how these factors differ at each stage of follicle growth remain poorly understood. The aim of this study was to isolate and evaluate the effect of recombinant growth and differentiation factor 9 (GDF9) on oocyte and granulosa cell growth at the primary and early secondary stages of preantral follicle growth during in vitro culture. METHODS: Primary stage follicles (diameters of 50-89 µm) and early secondary stage follicles (diameters of 90-120 µm) were isolated from immature mice, and individual, intact follicles were cultured in vitro in the presence and absence of recombinant GDF9. The effects of GDF9 on follicle growth were determined by the assessment of changes in the follicle volume during culture. The growth of the granulosa cell and oocyte compartments of the follicles was evaluated separately at each stage. RESULTS: GDF9 significantly increased the growth of isolated follicles at both the primary and early secondary follicle stages. Independent evaluation of the granulosa cell and oocyte compartments revealed that, while GDF9 promoted granulosa cell growth at both stages of folliculogenesis, oocyte growth was stage specific. GDF9 promoted growth of the oocyte at the primary, but not the early secondary, follicle stage. CONCLUSIONS: These findings demonstrate a stage-specific role for GDF9 in the regulation of oocyte and granulosa cell growth at the primary and early secondary stages of preantral follicle development.

Follow-up of multiple aneuploidies and single monosomies detected by noninvasive prenatal testing: implications for management and counseling.

OBJECTIVES: To determine the underlying biological basis for noninvasive prenatal testing (NIPT) results of multiple aneuploidies or autosomal monosomies. METHODS: Retrospective analysis of 113,415 tests to determine the study cohort, consisting of 138 (0.12%) cases reported as a single autosomal monosomy (n = 65), single trisomy with a sex chromosome aneuploidy (n = 36), or with multiple aneuploidies (n = 37). Clinical outcome information was reviewed and stratified into eight categories according to whether the karyotype or sonographic information agreed or disagreed with sequencing results. RESULTS: Of 67 cases with fetal or neonatal karyotypes available, 16 (24%) were partially or fully concordant with the NIPT result, 4 (6%) had aneuploidy on a reference chromosome, and 47 (70%) had normal fetal chromosomes, in which 5/47 had maternal malignancies reported. One case of maternal mosaic trisomy 8 was also detected. Of cases with no fetal karyotype information, ten had an abnormal clinical outcome, one was a normal live birth, and one reported maternal malignancy. CONCLUSIONS: Noninvasive prenatal test results of autosomal monosomy or multiple aneuploidies are rare but have a diversity of underlying biologic causes. Some reflect the fetal karyotype; some reflect the presence of other maternal or fetal chromosome abnormalities, and a small number are linked to maternal disease.

Noninvasive prenatal testing in the general obstetric population: clinical performance and counseling considerations in over 85 000 cases.

OBJECTIVE: The primary goal of this study was to provide clinically relevant information for appropriate patient counseling. METHOD: Demographics and test metrics were reviewed for 86 658 clinical cases. Outcome information was requested for samples reported as aneuploidy detected or suspected for chromosomes 21, 18, or 13; voluntary outcome reporting was encouraged for all discordant outcomes. RESULTS: Of 86 658 cases, 85 298 (98.4%) met inclusion criteria for result reporting. Of the 1360 (1.6%) cancellations, only 101 (0.1%) were for technical reasons. Average time to result was 3.3 business days. Aneuploidy was detected or suspected in 2142 (2.5%) samples. For aneuploidy detected cases with known clinical outcomes, the overall positive predictive value (PPV) was 83.5% (608/728); observed PPVs for trisomies 21, 18, and 13 ranged from 50.0 to 92.8%. As individual PPVs are determined by a patient's prior risk, we developed a chart for counseling patients on positive predictive value based on maternal age. CONCLUSION: This large-scale report reinforces that noninvasive prenatal testing is a highly accurate screen for fetal aneuploidy in the general obstetric population. Test improvements have facilitated a reduction in failure rates, time to result, and borderline results/unclassifiable results. We have developed a positive predictive value counseling tool to ensure appropriate patient education, counseling, and clinical utilization.

An Economic Analysis of Cell-Free DNA Non-Invasive Prenatal Testing in the US General Pregnancy Population.

OBJECTIVE: Analyze the economic value of replacing conventional fetal aneuploidy screening approaches with non-invasive prenatal testing (NIPT) in the general pregnancy population. METHODS: Using decision-analysis modeling, we compared conventional screening to NIPT with cell-free DNA (cfDNA) analysis in the annual US pregnancy population. Sensitivity and specificity for fetal aneuploidies, trisomy 21, trisomy 18, trisomy 13, and monosomy X, were estimated using published data and modeling of both first- and second trimester screening. Costs were assigned for each prenatal test component and for an affected birth. The overall cost to the healthcare system considered screening costs, the number of aneuploid cases detected, invasive procedures performed, procedure-related euploid losses, and affected pregnancies averted. Sensitivity analyses evaluated the effect of variation in parameters. Costs were reported in 2014 US Dollars. RESULTS: Replacing conventional screening with NIPT would reduce healthcare costs if it can be provided for $744 or less in the general pregnancy population. The most influential variables were timing of screening entry, screening costs, and pregnancy termination rates. Of the 13,176 affected pregnancies undergoing screening, NIPT detected 96.5% (12,717/13,176) of cases, compared with 85.9% (11,314/13,176) by conventional approaches. NIPT reduced invasive procedures by 60.0%, with NIPT and conventional methods resulting in 24,596 and 61,430 invasive procedures, respectively. The number of procedure-related euploid fetal losses was reduced by 73.5% (194/264) in the general screening population. CONCLUSION: Based on our analysis, universal application of NIPT would increase fetal aneuploidy detection rates and can be economically justified. Offering this testing to all pregnant women is associated with substantial prenatal healthcare benefits.

Detection of triploid, molar, and vanishing twin pregnancies by a single-nucleotide polymorphism-based noninvasive prenatal test.

OBJECTIVE: We sought to determine the ability of single-nucleotide polymorphism-based noninvasive prenatal testing (NIPT) to identify triploid, unrecognized twin, and vanishing twin pregnancies. STUDY DESIGN: The study included 30,795 consecutive reported clinical cases received for NIPT for fetal whole-chromosome aneuploidies; known multiple gestations were excluded. Cell-free DNA was isolated from maternal blood samples, amplified via 19,488-plex polymerase chain reaction, and sequenced. Sequencing results were analyzed to determine fetal chromosome copy number and to identify the presence of additional fetal haplotypes. RESULTS: Additional fetal haplotypes, indicative of fetal triploidy, vanishing twin, or undetected twin pregnancy, were identified in 130 (0.42%) cases. Clinical confirmation (karyotype for singleton pregnancies, ultrasound for multifetal pregnancies) was available for 58.5% (76/130) of cases. Of the 76 cases with confirmation, 42.1% were vanishing twin, 48.7% were viable twin, 5.3% were diandric triploids, and 3.9% were nontriploid pregnancies that lacked evidence of co-twin demise. One pregnancy had other indications suggesting triploidy but lacked karyotype confirmation. Of the 5 vanishing twin cases with a known date of demise, 100% of losses occurred in the first trimester; up to 8 weeks elapsed between loss and detection by NIPT. CONCLUSION: This single-nucleotide polymorphism-based NIPT successfully identified vanished twin, previously unrecognized twin, and triploid pregnancies. As vanishing twins are more likely to be aneuploid, and undetected residual cell-free DNA could bias NIPT results, the ability of this method to identify additional fetal haplotypes is expected to result in fewer false-positive calls and prevent incorrect fetal sex calls.

Clinical experience and follow-up with large scale single-nucleotide polymorphism-based noninvasive prenatal aneuploidy testing.

OBJECTIVE: We sought to report on laboratory and clinical experience following 6 months of clinical implementation of a single-nucleotide polymorphism-based noninvasive prenatal aneuploidy test in high- and low-risk women. STUDY DESIGN: All samples received from March through September 2013 and drawn ≥9 weeks' gestation were included. Samples that passed quality control were analyzed for trisomy 21, trisomy 18, trisomy 13, and monosomy X. Results were reported as high or low risk for fetal aneuploidy for each interrogated chromosome. Relationships between fetal fraction and gestational age and maternal weight were analyzed. Follow-up on outcome was sought for a subset of high-risk cases. False-negative results were reported voluntarily by providers. Positive predictive value (PPV) was calculated from cases with an available prenatal or postnatal karyotype or clinical evaluation at birth. RESULTS: Samples were received from 31,030 patients, 30,705 met study criteria, and 28,739 passed quality-control metrics and received a report detailing aneuploidy risk. Fetal fraction correlated positively with gestational age, and negatively with maternal weight. In all, 507 patients received a high-risk result for any of the 4 tested conditions (324 trisomy 21, 82 trisomy 18, 41 trisomy 13, 61 monosomy X; including 1 double aneuploidy case). Within the 17,885 cases included in follow-up analysis, 356 were high risk, and outcome information revealed 184 (51.7%) true positives, 38 (10.7%) false positives, 19 (5.3%) with ultrasound findings suggestive of aneuploidy, 36 (10.1%) spontaneous abortions without karyotype confirmation, 22 (6.2%) terminations without karyotype confirmation, and 57 (16.0%) lost to follow-up. This yielded an 82.9% PPV for all aneuploidies, and a 90.9% PPV for trisomy 21. The overall PPV for women aged ≥35 years was similar to the PPV for women aged <35 years. Two patients were reported as false negatives. CONCLUSION: The data from this large-scale report on clinical application of a commercially available noninvasive prenatal test suggest that the clinical performance of this single-nucleotide polymorphism-based noninvasive prenatal test in a mixed high- and low-risk population is consistent with performance in validation studies.