Assessment of a Simplified Cell-Free DNA Method for Prenatal Down Syndrome Screening.

BACKGROUND: Prenatal screening for common trisomies via cell-free (cfDNA) is usually implemented by technologies utilizing massively parallel sequencing, stringent environmental controls, complex bioinformatics, and molecular expertise. An alternative and less complex methodology utilizes rolling circle amplification (RCA). Further evaluation of its performance and related requirements are warranted. METHODS: At 16 sites, women at 10 to 20 weeks gestation provided informed consent, relevant information, and 2 to 3 blood samples. Samples shipped for testing were processed and stored. Women were enrolled at primary cfDNA screening, or following such screening at referral for diagnostic testing. RCA testing occurred post-enrollment, over 11 months. Diagnostic results and delivery notes determined clinical truth. Detection rates were based on confirmed trisomic pregnancies; false-positive rates were based on unaffected pregnancies from the general population. RESULTS: Detection rate for the common trisomies was 95.9% (117/122, 95% CI, 90.5%-98.5%); overall false-positive rate was 1.00% (22/2,205, 0.65%-1.51%). Test failure rate after repeat testing was 0.04%. When assay standard deviations were below pre-specified levels, the overall false-positive rate was much lower at 0.30% (P < 0.001). Fetal sex calls were correct for 99.7%. One technician analyzed 560 samples over 2 weeks, a rate of 14 000/year. CONCLUSIONS: Our assessment of this simplified cfDNA-based system for prenatal screening for common trisomies performed in a prenatal screening laboratory is encouraging. Improved detection, low failure rates and rapid reporting can be achieved by collecting 2 samples. Future priorities should include achieving higher run precision using a single collection tube. CLINICALTRIALS.GOV REGISTRATION NUMBER: NCT03087357.

HE4 and CA125 serum biomarker monitoring in women with epithelial ovarian cancer.

BACKGROUND: CA125 is the gold standard serum biomarker for monitoring patients with epithelial ovarian cancer (EOC). Human epididymal protein 4 (HE4) is a novel serum biomarker for EOC patients. OBJECTIVE: The objective of this trial was to examine the utility of measuring serum HE4 levels for monitoring EOC patients and to compare HE4 performance parameters to serum CA125. METHODS: A retrospective trial using residual longitudinal serum samples drawn during treatment and monitoring from EOC patients. Serum CA125 and HE4 levels were analyzed at each time point, and a velocity of change was calculated and correlated with clinical status. The null hypothesis was that HE4 is inferior to CA125, and this was tested using concordance and two-sided Fisher's exact testing. McNemar's test was used to assess the overall agreement of the two assays with the clinical status. RESULTS: A total of 129 patients with 272 separate clinical periods and 1739 events (serum samples) were evaluated. Using a 25% change in serum biomarker levels to indicate change in disease status, the accuracy and NPV determined for HE4 versus CA125 were 81.8% versus 82.6% (p = 0.846) and 87.4% versus 89.7% (p = 0.082), respectively. Concordance comparison of HE4 accuracy / CA125 accuracy was 0.990, indicating HE4 was not inferior to CA125 (McNemar's test p-value = 0.522). Performing a velocity of change analysis, the accuracy and NPV determined for HE4 versus CA125 were 78.3% versus 78.6% (p = 0.995) and 74.9% versus 76.3% (p = 0.815), respectively. Concordance comparison of HE4 velocity accuracy / CA125 velocity accuracy was 0.996, again indicating HE4 was not inferior to CA125 (McNemar's test p-value = 0.884). The combination of HE4 and CA125 velocity changes showed a similar accuracy of 81.3% (p = 0.797 compared to HE4 and CA125 alone) and NPV of 81.1% (p≥0.172 compared to HE4 and CA125 alone), and an increased sensitivity of 70.5% (p≤0.070 compared to HE4 and CA125 alone). CONCLUSION: HE4 is equivalent to CA125 for monitoring of EOC patients. The combination of CA125 and HE4 velocities is superior to either marker alone.

Preeclampsia at delivery is associated with lower serum vitamin D and higher antiangiogenic factors: a case control study.

BACKGROUND: Preeclampsia is characterized by decreased trophoblastic angiogenesis leading to abnormal invasion of spiral arteries, shallow implantation and resulting in compromised placentation with poor uteroplacental perfusion. Vitamin D plays an important role in pregnancy influencing implantation, angiogenesis and placental development. The objective of this study was to determine whether there is an association between serum vitamin D levels, and anti-angiogenic factors at the time of delivery and the occurrence of preeclampsia. METHODS: This nested case control study analyzed frozen serum samples at the time of delivery and related clinical data from women with singleton liveborn pregnancies who had participated in studies of the NICHD Stillbirth Collaborative Research Network. Women with a recorded finding of preeclampsia and who had received magnesium sulfate treatment prior to delivery were considered index cases (N = 56). Women without a finding of preeclampsia were controls (N = 341). RESULTS: Women with preeclampsia had 14.5% lower serum vitamin D levels than women in the control group (16.5 ng/ml vs. 19 ng/ml, p = 0.014) with 64.5% higher sFlt-1 levels (11,600 pg/ml vs. 7050 pg/ml, p < 0.001) and greater than 2 times higher endoglin levels (18.6 ng/ml vs. 8.7 ng/ml, < 0.001). After controlling for gestational age at delivery and maternal BMI, vitamin D levels were 0.88 times lower (P = 0.051), while endoglin levels were 2.5 times higher and sFlt-1 levels were 2.1 times higher than in control pregnancies (P < 0.001). CONCLUSIONS: Women with preeclampsia at time of delivery have higher maternal antiangiogenetic factors and may have lower maternal serum vitamin D levels. These findings may lead to a better understanding of the underlying etiology of preeclampsia as well as possible modifiable treatment options which could include assuring adequate levels of maternal serum vitamin D prior to pregnancy.

Oxidative and carbonyl stress in pregnant women with obstructive sleep apnea.

PURPOSE: Pregnant women are particularly susceptible to sleep-disordered breathing. Obstructive sleep apnea (OSA) in pregnancy is associated with poor pregnancy and fetal outcomes. Oxidative stress caused by intermittent hypoxemia and reoxygenation may impact pregnancy health. We hypothesize that pregnant women with OSA have a pronounced oxidative stress profile. METHODS: A case-control study was performed to study oxidative stress markers in the serum of pregnant women with or without OSA. Patients with OSA were identified between 2003 and 2009. Contemporaneous controls were pregnant subjects without apnea, gasping, or snoring around the time of delivery. Serum markers of oxidative and carbonyl stress were measured by spectrophotometric/fluorometric methods. Multiple linear regression analysis was used with a model including age, body mass index at delivery, history of diabetes, and gestational age. RESULTS: Serum samples from 23 OSA cases and 41 controls were identified. Advanced oxidation protein products, a marker for oxidative stress, and advanced glycation end products (AGEs), a marker for carbonyl stress, were significantly lower in women with OSA than in controls (p value <0.0001). Total antioxidant capacity was higher in women with OSA in comparison to controls (p value <0.0001). The difference in AGEs remained significant even after adjusting for confounders. CONCLUSION: Contrary to our hypothesis, the results of this study suggest that pregnant women with OSA have higher antioxidant capacity and lower oxidative and carbonyl stress markers compared to controls, suggesting a possible protective effect of intermittent hypoxia. Whether OSA in pregnancy impacts oxidative stress differently than OSA in the general population remains to be confirmed.

The clinical utility of DNA-based screening for fetal aneuploidy by primary obstetrical care providers in the general pregnancy population.

OBJECTIVE: To assess the clinical utility of cell-free DNA (cfDNA)-based screening for aneuploidies offered through primary obstetrical care providers to a general pregnancy population. METHODS: Patient educational materials were developed and validated and providers were trained. Serum was collected for reflexive testing of cfDNA failures. Providers and patients were surveyed concerning knowledge, decision making, and satisfaction. Pregnancy outcome was determined by active or passive ascertainment. RESULTS: Between September 2014 and July 2015, 72 providers screened 2,691 women. The five largest participating practices increased uptake by 8 to 40%. Among 2,681 reports, 16 women (0.6%) were screen-positive for trisomy 21, 18, or 13; all saw genetic professionals. Twelve were confirmed (positive predictive value (PPV), 75%; 95% CI, 48-93%) and four were false-positives (0.15%). Of 150 failures (5.6%), 79% had a negative serum or subsequent cfDNA test; no aneuploidies were identified. Of 100 women surveyed, 99 understood that testing was optional, 96 had their questions answered, and 95 received sufficient information. Pretest information was provided by the physician/certified nurse midwife (55) or office nurse/educator (40); none was provided by genetic professionals. CONCLUSION: This first clinical utility study of cfDNA screening found higher uptake rates, patient understanding of basic concepts, and easy incorporation into routine obstetrical practices. There were no reported cases of aneuploidy among cfDNA test failures.Genet Med advance online publication 12 January 2017.

Assessment of serum HE4 levels throughout the normal menstrual cycle.

BACKGROUND: Human epididymis protein 4 is a serum biomarker to aid in differentiating benign and malignant disease in women with a pelvic mass. Interpretation of human epididymis protein 4 results relies on robust normative data. OBJECTIVE: The purpose of this study was to evaluate whether human epididymis protein 4 levels are variable in women during the normal menstrual cycle. STUDY DESIGN: Healthy women, 18-45 years old, with regular menstrual cycles were recruited from community gynecologic practices in Rhode Island. Women consented to enroll and to participate by the donation of blood and urine samples at 5 specific times over the course of each cycle. Levels of reproductive hormones and human epididymis protein 4 were determined. Data were analyzed with the use of linear regression after log transformation. RESULTS: Among 74 enrolled cycles, 53 women had confirmed ovulation during the menstrual cycle and completed all 5 sample collections. Levels of estradiol, progesterone, and luteinizing hormone displayed the expected menstrual cycle patterns. Levels of human epididymis protein 4 in serum were relatively stable across the menstrual cycle, except for a small ovulatory (median, 37.0 pM) increase. Levels of human epididymis protein 4 in urine, after correction for creatinine, displayed the same pattern of secretion observed in serum. CONCLUSION: Serum human epididymis protein 4 levels are relatively stable across the menstrual cycle of reproductive-aged women and can be determined on any day to evaluate risk of ovarian malignancy. A slight increase is expected at ovulation; but even with this higher human epididymis protein 4 level, results are well within the healthy reference range for women (<120 pM). Levels of human epididymis protein 4 in urine warrant further investigation for use in clinical practice as a simple and convenient sample.

Use of antimüllerian hormone to predict the menopausal transition in HIV-infected women.

BACKGROUND: HIV infection has been associated with early menopausal onset, which may have adverse long-term health consequences. Antimüllerian hormone, a biomarker of ovarian reserve and gonadal aging, is reduced in HIV-infected women. OBJECTIVE: We sought to assess the relationship of antimüllerian hormone to age of menopause onset in HIV-infected women. STUDY DESIGN: We used antimüllerian hormone levels measured in plasma in 2461 HIV-infected participants from the Women's Interagency HIV Study to model the age at final menstrual period. Multivariable normal mixture models for censored data were used to identify factors associated with age at final menstrual period. RESULTS: Higher antimüllerian hormone at age 40 years was associated with later age at final menstrual period, even after multivariable adjustment for smoking, CD4 cell count, plasma HIV RNA, hepatitis C infection, and history of clinical AIDS. Each doubling of antimüllerian hormone was associated with a 1.5-year increase in the age at final menstrual period. Median age at final menstrual period ranged from 45 years for those in the 10th percentile of antimüllerian hormone to 52 years for those in the 90th percentile. Other factors independently associated with earlier age at final menstrual period included smoking, hepatitis C infection, higher HIV RNA levels, and history of clinical AIDS. CONCLUSION: Antimüllerian hormone is highly predictive of age at final menstrual period in HIV-infected women. Measuring antimüllerian hormone in HIV-infected women may enable clinicians to predict risk of early menopause, and potentially implement individualized treatment plans to prevent menopause-related comorbidities and to aid in interpretation of symptoms.

Correlation between follicular fluid levels of sRAGE and vitamin D in women with PCOS.

PURPOSE: The pro-inflammatory advanced glycation end products (AGEs) and their anti-inflammatory soluble receptors, sRAGE, play a role in the pathogenesis of PCOS. There is a correlation between vitamin D (vit D) and sRAGE in the serum, whereby vit D replacement increases serum sRAGE levels in women with PCOS, thus incurring a protective anti-inflammatory role. OBJECTIVE: This study aims to compare levels of sRAGE, N-carboxymethyl-lysine (CML; one of the AGEs), and 25-hydroxy-vit D in the follicular fluid (FF) of women with or without PCOS, and to evaluate the correlation between sRAGE and 25-hydroxy-vit D in the FF. MATERIAL AND METHODS: Women with (n = 12) or without (n = 13) PCOS who underwent IVF were prospectively enrolled. RESULTS: Women with PCOS had significantly higher anti-Mullerian hormone levels, higher number of total retrieved and mature oocytes, and higher number of day 3 and day 5 embryos formed. Compared to women without PCOS, women with PCOS had significantly lower FF sRAGE levels. In women with PCOS, in women without PCOS, and in all participants together, there was a significant positive correlation between sRAGE and 25-hydroxy-vit D. sRAGE positively correlated with CML in women without PCOS but not in women with PCOS. CONCLUSIONS: In women with PCOS, the low ovarian levels of the anti-inflammatory sRAGE suggest that sRAGE could represent a biomarker and a potential therapeutic target for ovarian dysfunction in PCOS. Whether there is a direct causal relationship between sRAGE and vit D in the ovaries remains to be determined.

Where have all the trisomies gone?

Providing reliable prenatal screening performance estimates is critical for patient counseling and policy-making. Women who choose prenatal screening for aneuploidy are likely to be concerned not only with the common aneuploidies but with all causes of intellectual disability and serious birth defects. Sequential prenatal screening (combined serum and ultrasound testing) for aneuploidy detection commonly is offered as a primary screening test. Among women identified as screen positive, cell-free (cf)DNA has been added recently as a secondary, noninvasive screening option, before the consideration of invasive diagnostic testing (eg, amniocentesis and karyotype). With the anticipation of lower costs in the future, cfDNA might be an alternative to sequential screening in the general population. Sequential and cfDNA tests are both noninvasive, and both identify common aneuploidies. Screening via cfDNA detects more common chromosome abnormalities (eg, trisomy 21, sex trisomies). Sequential screening can identify other aneuploidies (eg, triploidy), as well as chromosome abnormalities associated with fetal structural abnormalities. When the advantages and disadvantages of routine sequential screening with routine cfDNA screening are compared, one important measure is the proportion and severity of chromosome abnormalities identified. When reporting these detection rates, authors need to carefully consider the impact of multiple well-described biases. For women to make informed choices in situations of this type, determining reliable comparative performance estimates is crucial.

Is maternal plasma DNA testing impacting serum-based screening for aneuploidy in the United States?

PURPOSE: We sought to determine whether tests for fetal aneuploidy based on next-generation sequencing of cell-free DNA in maternal circulation have had an impact on routine serum-based screening in the general pregnant population. METHODS: We compared results from laboratory surveys in 2011 and 2014 that reported types of prenatal serum screening tests and numbers of tests performed. Testing records from two prenatal serum screening laboratories examined temporal trends in the proportion of screened women 35 years of age and older from 2008 (or 2009) to 2014. RESULTS: The 82 laboratory survey results available for comparison showed that 1.7 million women were screened in 2014, a 5% increase over 2011. In the two screening laboratories, the proportion of screened women age 35 and older increased for several years but then experienced reductions of 8 and 18% by mid-2014 when compared with the highest rates observed. CONCLUSION: As of 2014, maternal plasma DNA testing appears to have had only a minor impact on serum screening rates in the United States. Ongoing surveillance has the potential to determine if, and when, DNA testing begins to replace serum testing as a primary screen for Down syndrome in the United States.

Assessing the risk of ovarian malignancy algorithm for the conservative management of women with a pelvic mass.

OBJECTIVE: To evaluate the use of as an aid in the identification of women who can safely undergo conservative, non-surgical management. METHODS: All patients referred to the Program in Women's Oncology for surgery with a pelvic mass are evaluated at a prospective multidisciplinary tumor board (TB) where ROMA and imaging are used for management recommendations. This study evaluated women presented to TB with a pelvic mass between 2009 and 2013 who had either surgical or conservative management. RESULTS: Of the 498 patients assessed, 392 (79%) had benign disease, 22 (4%) had LMP tumors, 28 (6%) had stage I-II epithelial ovarian cancer (EOC), 36 (7%) had stage III-IV EOC and 20 (4%) had non-EOC. Using clinical assessment in conjunction with ROMA, the TB recommended observation in 188 (37.8%) women. All patients diagnosed with an invasive malignancy were recommended for surgery by the TB. In the 315 patients managed surgically, 212 were found to have benign disease and 84 women were diagnosed with an invasive malignancy. The sensitivity for the initial TB recommendations using ROMA in conjunction with clinical judgment for detecting malignancy was 100% with a specificity of 47.7% and a NPV of 100%. When including low malignant potential tumors the sensitivity was 99.1%. For stage I-IV EOC ROMA alone had a sensitivity of 95.3%. CONCLUSIONS: ROMA in conjunction with clinical assessment can safely identify women for conservative management.

Evaluating first trimester maternal serum screening combinations for Down syndrome suitable for use with reflexive secondary screening via sequencing of cell free DNA: high detection with low rates of invasive procedures.

OBJECTIVES: Examine primary Down syndrome screening using combinations of first trimester serum markers, with and without sequencing of cell free DNA as a secondary reflexive test. METHODS: Samples from 40 Down syndrome cases were matched with five control samples and tested for PAPP-A, free ß, AFP, inhibin-A and PlGF. Results were converted to weight-adjusted multiples of the median (MoM) and population parameters computed. Monte Carlo simulation modeled Down syndrome detection and false positive rates for various marker combinations. After reflexive DNA testing, the revised detection and false positive rates were also computed. RESULTS: At a primary false positive rate of 20%, the baseline combination (maternal age, PAPP-A and free ß) detected 86.9%. Adding AFP or PlGF increased detection to 89.8% and 89.5%, respectively. Adding AFP and PlGF, AFP and inhibin-A, or all three markers, detected 93.7%, 94.1% and 95.5%, respectively. Modeling reflexive cf DNA testing results in little loss in detection (1%), but false positive rates fall to 0.2%. CONCLUSION: First trimester reflexive testing does not require nuchal translucency measurements, and has high detection and very low rates of invasive procedures. However, timing of DNA sample collection and the costs of sample collection and DNA testing need to be considered before implementation.

Evaluation of patient education materials: the example of circulating cell free DNA testing for aneuploidy.

Informed consent is the process by which the treating health care provider discloses appropriate information to a competent patient so that the patient may make a voluntary choice to accept or refuse treatment. When the analysis of circulating cell free DNA (ccfDNA) became commercially available in 2011 through the Prenatal Diagnostic Laboratory at Women & Infants Hospital of Providence, Rhode Island to "high-risk" women, it provided an opportunity to examine how commercial laboratories informed potential consumers. We identified, via an internet search, four laboratories offering such testing in the United States and one in Europe. We evaluated patient educational materials (PEMs) from each using the Flesch Reading Ease method and a modified version of the Suitability Assessment of Materials (SAM) criteria. Pamphlets were also reviewed for their inclusion of content recommendations from the International Society for Prenatal Diagnosis, the National Society of Genetic Counselors, the American College of Obstetricians and Gynecologists jointly with the Society of Maternal Fetal Medicine, and the American College of Genetics and Genomics. Reading levels were typically high (10th-12th grade). None of the pamphlets met all SAM criteria evaluated nor did any pamphlet include all recommended content items. To comply with readability and content recommendations more closely, Women & Infants Hospital created a new pamphlet to which it applied the same criteria, and also subjected it to focus group assessment. These types of analyses can serve as a model for future evaluations of similar patient educational materials.

Placenta-secreted circulating markers in pregnant women with obstructive sleep apnea.

AIMS: Obstructive sleep apnea (OSA) is associated with placenta-mediated adverse clinical outcomes. We aimed at comparing placenta-secreted proteins, such as first and second trimester Down syndrome screening markers which have been linked to preeclampsia, and markers of angiogenesis in pregnant women with OSA, and pregnant controls at low risk for OSA. METHODS: A case-control study of pregnant women with OSA and controls at low risk for OSA was performed. Levels of first and second trimester markers were reported as multiple of median (MoM), and adjusted for body mass index (BMI). Stored samples were tested for markers of angiogenesis and adjusted for gestational age, BMI, and chronic hypertension. RESULTS: A total of 24 women with OSA and 166 controls had screening markers. BMI was higher in cases compared to controls, P=0.01. MoM levels of placenta associated plasma protein-A (PAPP-A) were significantly lower in cases versus controls, even after adjusting for BMI (0.52 IQR 0.48 vs. 1.01 IQR 0.63, P=0.009). The ratio of soluble vascular endothelial growth factor receptor 1 to placental growth factor was significantly higher in cases than controls, even after adjusting for confounders (4.42 IQR 2.52 vs. 2.93 IQR 2.01, P=0.009). CONCLUSION: Circulating placenta-secreted glycoproteins and markers of angiogenesis are altered in pregnant women with OSA.

Maternal plasma DNA testing for aneuploidy in pregnancies achieved by assisted reproductive technologies.

PURPOSE: We sought to compare measurements of circulating cell-free DNA as well as Down syndrome test results in women with naturally conceived pregnancies with those conceived using assisted reproductive technologies. METHODS: Data regarding assisted reproductive technologies were readily available from seven enrollment sites participating in an external clinical validation trial of nested case/control design. Measurements of circulating cell-free fetal and total DNA, fetal fraction (ratio of fetal to total DNA), chromosome-specific z-scores, and karyotype results were available for analysis. RESULTS: Analyses were restricted to 632 euploid (5.2% assisted reproductive technologies) and 73 Down syndrome (13.7% assisted reproductive technologies), including 16 twin pregnancies. No differences were found for fetal or total circulating cell-free DNA, or for the fetal fraction in euploid (P = 0.70) or Down syndrome (P = 0.58) pregnancies by method of conception. There appeared to be systematic z-score reductions for chromosomes 21, 18, and 13 in assisted reproductive technologies versus natural euploid pregnancies (P = 0.048, 0.0032, and 0.36, respectively). CONCLUSION: Assisted reproductive technologies and naturally conceived pregnancies contribute similar levels of circulating cell-free DNA into maternal circulation. Small differences in the z-scores of pregnancies achieved by assisted reproductive technologies were observed and do not appear to be test-related artifacts. However, the findings need confirmation before any consideration of changes to testing and reporting protocols.

The impact of maternal plasma DNA fetal fraction on next generation sequencing tests for common fetal aneuploidies.

Maternal plasma contains circulating cell-free DNA fragments originating from both the mother and the placenta. The proportion derived from the placenta is known as the fetal fraction. When measured between 10 and 20 gestational weeks, the average fetal fraction in the maternal plasma is 10% to 15% but can range from under 3% to over 30%. Screening performance using next-generation sequencing of circulating cell-free DNA is better with increasing fetal fraction and, generally, samples whose values are less than 3% or 4% are unsuitable. Three examples of the clinical impact of fetal fraction are discussed. First, the distribution of test results for Down syndrome pregnancies improves as fetal fraction increases, and this can be exploited in reporting patient results. Second, the strongest factor associated with fetal fraction is maternal weight; the false negative rate and rate of low fetal fractions are highest for women with high maternal weights. Third, in a mosaic, the degree of mosaicism will impact the performance of the test because it will reduce the effective fetal fraction. By understanding these aspects of the role of fetal fraction in maternal plasma DNA testing for aneuploidy, we can better appreciate the power and the limitations of this impressive new methodology.

Validation of a monoclonal unconjugated estriol antibody for use in prenatal maternal serum screening.

OBJECTIVES: Unconjugated estriol (uE3) is used as a marker for fetal aneuploidy in maternal serum screening tests. The goal of this study was to examine the validity of a new immunoassay for uE3 that uses a monoclonal antibody (m-uE3) rather than the more commonly used polyclonal antibody (p-uE3). SETTING: Assays were performed in the Special Chemistry laboratory at Women and Infants Hospital of Rhode Island. METHODS: Residual fresh (n = 100) and frozen (n = 533) second trimester serum samples from routine clinical care were tested using p-uE3 and/or m-uE3 assays. Assay results were compared between methods using Bland-Altman plots. A median equation was developed for m-uE3 results. Down syndrome risks were compared between the two assays in a case-control sample set (21 cases each matched with five controls for the completed week of gestation, duration of freezer storage and race). RESULTS: Log-transformed serum uE3 levels were highly correlated between the assays (r = 0.93, p < 0.001), with the m-uE3 assay levels yielding, on average, 23% higher (standard deviation of differences in log uE3 concentrations = 0.07) results. Assay and gestation-based median equations were calculated and used to convert m-uE3 concentrations to multiples of the median (MoM). The m-uE3 MoM values fit a log Gaussian distribution well with a log standard deviation of 0.11. Down syndrome risk results were not significantly different between assays. CONCLUSIONS: The m-uE3 assay, with results expressed in MoMs, is suitable for screening and as a monoclonal-based assay offers the advantage of a predictable and indefinite supply of antibody to perform the assay.

Cell-free DNA-based prenatal screening via rolling circle amplification: Identifying and resolving analytic issues.

OBJECTIVE: A rolling circle amplification (RCA) based commercial methodology using cell-free (cf)DNA to screen for common trisomies became available in 2018. Relevant publications documented high detection but with a higher than expected 1% false positive rate. Preliminary evidence suggested assay variability was an issue. A multi-center collaboration was created to explore this further and examine whether subsequent manufacturer changes were effective. METHODS: Three academic (four devices) and two commercial (two devices) laboratories provided run date, chromosome 21, 18, and 13 run-specific standard deviations, number of samples run, and reagent lot identifications. Temporal trends and between-site/device consistency were explored. Proportions of run standard deviations exceeding pre-specified caps of 0.4%, 0.4% and 0.6% were computed. RESULTS: Overall, 661 RCA runs between April 2019 and July 30, 2022 tested 39,756 samples. In the first 24, subsequent 9, and final 7 months, proportions of capped chromosome 21 runs dropped from 39% to 22% to 6.0%; for chromosome 18, rates were 76%, 36%, and 4.0%. Few chromosome 13 runs were capped using the original 0.60%, but capping at 0.50%, rates were 28%, 16%, and 7.6%. Final rates occurred after reformulated reagents and imaging software modifications were fully implemented across all devices. Revised detection and false positive rates are estimated at 98.4% and 0.3%, respectively. After repeat testing, failure rates may be as low as 0.3%. CONCLUSION: Current RCA-based screening performance estimates are equivalent to those reported for other methods, but with a lower test failure rate after repeat testing.

Methodological approach for an integrated female-specific study of anxiety and smoking comorbidity.

Two primary ovarian hormones that fluctuate across the female menstrual cycle-estradiol and progesterone-have been independently linked in separate literatures to nicotine reinforcement and anxiety psychopathology. We identify existing methodological limitations in these literatures, describe an example protocol that was developed to address such limitations, highlight case examples, and offer insights on the resulting advantages and challenges. This protocol was an observational, prospective, within-subjects study of female cigarette smokers who were followed over the course of a complete menstrual cycle. Non-treatment seeking, female cigarette smokers (N = 50), between the ages of 18-40 who have a normal menstrual cycle (25-35 days in length) were recruited from the community. Females with anxiety or mood psychopathology represented 38.0% of the sample. Salivary progesterone and estradiol were assessed each morning via at-home saliva collection methods. Self-reported within-day momentary ratings of anxiety and nicotine reinforcement were collected using ecological momentary assessment (EMA) via a mobile app. Protocol compliance was >85%. Within- and between-subjects heterogeneity was observed in the progesterone and estradiol, anxiety, and nicotine craving measures, especially in the context of anxiety psychopathology. We aimed to integrate the anxiety and nicotine dependence literatures and advance the empirical study of the role of ovarian hormones. This protocol reflects an intensive, yet feasible approach to collecting daily-level naturalistic data related to estradiol, progesterone, anxiety, and nicotine reinforcement.