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Background: Combined first‐trimester screening (cFTS) for fetal anomalies involves maternal serum screening for biochemical markers and measurement of the nuchal translucency (NT) by ultrasound. Noninvasive prenatal screening (NIPS) analyses cell‐free DNA present in a maternal blood sample for presence of fetal chromosomal aneuploidies. Aims: To compare NIPS with cFTS as frontline screening in a public hospital in Australia. Materials and methods: Women were offered NIPS in addition to the usual cFTS routinely offered to all women at a public hospital in NSW, Australia. The cFTS sample was collected at ten weeks' gestation and the NIPS sample at 12 weeks' gestation at the ultrasound appointment. Results: In a low‐risk population of 997 women, frontline NIPS had a screen‐positive rate of 0.5% (5/997) vs 4.2% (42/997) with cFTS. cFTS correctly identified one trisomy 21 case and one trisomy 18 case; however, there were two trisomy 18 false negatives. Of five positive NIPS calls, four were correctly identified as trisomy 21 (one) and trisomy 18 (three); there were no NIPS false negatives. Overall, the false‐positive rate with NIPS was 0.1% vs 4.0% by cFTS. Conclusions: The lower screen‐positive rate with NIPS for common trisomies was a result of the significantly lower false‐positive rate with NIPS. Consequently, NIPS as first‐line screening, even if funded by the hospital, may provide cost savings. We believe NIPS should be used from ten weeks' gestation in conjunction with morphology ultrasound for routine first‐trimester prenatal management. [ABSTRACT FROM AUTHOR]

Background: Perinatal mental ill‐health is a global health priority. Mental health screening during pregnancy is a routine part of clinical practice in many public hospital obstetric services across Australia, but implementation in the private hospital system has lagged. Aims: This study explored health professionals' perspectives on the Pre‐admission Midwife Appointment Program (PMAP), an antenatal mental health screening program at the Mater Hospital, Sydney. Materials and Methods: Nine midwives and three medical specialists participated in focus groups or individual interviews; key themes were determined using thematic qualitative analysis. Results: Five major themes and three sub‐themes were identified: immediate benefits to women (identifying women at risk; referrals to support services; supporting and educating women); enhanced overall quality of care at the hospital; the dilemma of partners attending; factors that make the program successful; and recommendations for improvement. Conclusions: Results will inform the implementation of antenatal mental health screening programs at other private hospitals across Australia. [ABSTRACT FROM AUTHOR]

The records of women attending a large Australian regional hospital for antenatal care were retrospectively analysed to determine what proportion had undergone or been offered first trimester screening for fetal abnormalities; only 609 (54%) of 1114 women had undergone or been offered screening. Younger women, multiparous women and women living in rural Australia were less likely to be offered screening. Barriers to screening and solutions for overcoming these need to be identified to improve access and equality in antenatal screening for all women. [ABSTRACT FROM AUTHOR]

Cell‐free DNA screening has quickly become established in Australia as an accurate – albeit costly – prenatal screening test for trisomy 21, 18 and 13. It is also commonly used for the detection of sex chromosome abnormalities. The increasing number of prenatal screening pathways available to women has increased the complexity of pretest counselling. Concurrent advances in diagnostic testing with the widespread use of chromosomal microarrays create further challenges for the continuing education of clinicians and health consumers. This article aims to answer common clinical questions in this rapidly evolving field and complements the recently updated Royal Australian and New Zealand College of Obstetricians and Gynaecologists Statement on Prenatal Screening for Fetal Chromosome and Genetic Conditions. [ABSTRACT FROM AUTHOR]

Background: Advances in technology can bring great benefits to human health, but their implementation may be influenced by socioeconomic factors, particularly in the field of prenatal screening for Down syndrome. Aim: To analyse screening test indications for, and diagnostic yield of, invasive prenatal diagnostic testing (PNDx) according to socioeconomic status. Methods: Retrospective analysis of population‐based data on PNDx and karyotype results for 2014–2015 in the Australian state of Victoria. Women having PNDx < 25 weeks due to combined first trimester screening (CFTS), second trimester serum screening (STSS), or noninvasive prenatal testing (NIPT) results were included. PNDx data were analysed by indication and maternal Index of Relative Socio‐economic Advantage and Disadvantage (IRSAD), the latter determined by postcode. Results: There were 145 206 births in 2014–2015; 1906 women underwent PNDx for the indication of CFTS (70.1%), NIPT (17.8%) or STSS (12.0%). Covariates positively associated with NIPT‐indicated PNDx, compared with CFTS‐indicated testing, were residence in a region of socioeconomic advantage, metropolitan status and maternal age. Women from the most advantaged regions had higher adjusted odds ratios (aOR) of NIPT‐indicated testing compared with women from disadvantaged regions (aOR 5.72, 95% CI: 2.95–11.09). The diagnostic yield of PNDx increased with socioeconomic region, from 14% in the lowest IRSAD quintile to 31.2% in the highest (P < 0.0001). Conclusion: Population‐based data reveal significant disparities in screening indications for PNDx and hence, in diagnostic yield, according to socioeconomic region. This finding may have ethical and policy implications for prenatal screening in Australia. [ABSTRACT FROM AUTHOR]

Background Contingent screening for trisomy 21 using non-invasive prenatal testing has the potential to reduce invasive diagnostic testing and increase the detection of trisomy 21. Aim To describe the diagnostic and economic performance of prenatal screening models for trisomy 21 that use non-invasive prenatal testing as a contingent screen across a range of combined first trimester screening risk cut-offs from a public health system perspective. Methods Using a hypothetical cohort of 300 000 pregnancies, we modelled the outcomes of 25 contingent non-invasive prenatal testing screening models and compared these to conventional screening, offering women with a high-risk (1 > 300) combined first trimester screening result an invasive test. The 25 models used a range of risk cut-offs. High-risk women were offered invasive testing. Intermediate-risk women were offered non-invasive prenatal testing. We report the cost of each model, detection rate, costs per diagnosis, invasive tests per diagnosis and the number of fetal losses per diagnosis. Results The cost per prenatal diagnosis of trisomy 21 using the conventional model was $51 876 compared to the contingent models which varied from $49 309-66 686. The number of diagnoses and cost per diagnosis increased as the intermediate-risk threshold was lowered. Results were sensitive to trisomy 21 incidence, uptake of testing and cost of non-invasive prenatal testing. Conclusion Contingent non-invasive prenatal testing models using more sensitive combined first trimester screening risk cut-offs than conventional screening improved the detection rate of trisomy 21, reduced procedure-related fetal loss and could potentially be provided at a lower cost per diagnosis than conventional screening. [ABSTRACT FROM AUTHOR]

Background There are limited data regarding noninvasive prenatal testing ( NIPT) in low-risk populations, and the ideal aneuploidy screening model for a pregnant population has yet to be established. Aims To assess the implementation of NIPT into clinical practice utilising both first- and second-line screening models. Materials and Methods Three private practices specialising in obstetric ultrasound and prenatal diagnosis in Australia offered NIPT as a first-line test, ideally followed by combined first-trimester screening ( cFTS), or as a second-line test following cFTS, particularly in those with a calculated risk between 1:50 and 1:1000. Results NIPT screening was performed in 5267 women and as a first-line screening method in 3359 (63.8%). Trisomies 21 and 13 detection was 100% and 88% for trisomy 18. Of cases with known karyotypes, the positive predictive value ( PPV) of the test was highest for trisomy 21 (97.7%) and lowest for monosomy X (25%). Ultrasound detection of fetal structural abnormality resulted in the detection of five additional chromosome abnormalities, two of which had high-risk cFTS results. For all chromosomal abnormalities, NIPT alone detected 93.4%, a contingent model detected 81.8% ( P = 0.097), and cFTS alone detected 65.9% ( P < 0.005). Conclusions NIPT achieved 100% T21 detection and had a higher DR of all aneuploidy when used as a first-line test. Given the false-positive rate for all aneuploidies, NIPT is an advanced screening test, rather than a diagnostic test. The benefit of additional cFTS was the detection of fetal structural abnormalities and some unusual chromosomal abnormalities. [ABSTRACT FROM AUTHOR]

Objective To provide data on how screen-positive and detection rates of first trimester prenatal screening for fetal Down syndrome vary with changes in the risk cut-off and maternal age to inform contingency criteria for publicly funded noninvasive prenatal testing. Materials and Methods First trimester screening and diagnostic data were collected for all women attending for first trimester fetal aneuploidy screening in Western Australia between 2005 and 2009. Prenatal screening and diagnostic data were linked to pregnancy outcomes, including data from the Midwives' Notification System and the Western Australian Registry of Developmental Anomalies. The prevalence of Down syndrome and performance of screening by risk cut-off and/or for women >35 years were analysed. Results The current screening risk cut-off of 1:300 has screen-positive and detection rates of 3.5% and 82%. The screen-positive rate increases by 0.7-0.8% for each 100 point change in risk, up to 19.2% at 1:2500 (96% detection rate). Including all women >35 years as screen positive would increase the screen-positive rate and detection rates to 30.2% and 97.2%. Conclusion Variation in screening risk cut-off and the use of maternal age to assess eligibility for noninvasive testing could significantly impact the demand for, and cost of, the test. A contingent first trimester screening approach for risk assessment is superior to the use of a combination of screening and maternal age alone. These data will inform decisions regarding the criteria used to determine eligibility for publicly funded noninvasive prenatal testing. [ABSTRACT FROM AUTHOR]

Aim To describe the potential impact of using noninvasive prenatal testing ( NIPT) as a second-tier test, on the diagnosis and outcomes of pregnancies identified as high risk through first trimester screening ( FTS) in a cohort of real pregnancies. Materials and Methods Western Australian FTS and diagnostic data (2007-2009) were linked to pregnancy outcomes. Karyotype results from invasive prenatal testing in high-risk women were analysed. The outcomes of abnormal results that would not be detected by NIPT, assuming a panel of trisomy 21/18/13 and sex chromosome aneuploidies, and the likelihood of diagnosis in a screening model using NIPT as a second-tier test are described. Results Abnormal karyotype results were reported in 224 of 1488 (15%) women with high-risk pregnancies having invasive diagnostic testing. NIPT potentially would have identified 85%. The 33 abnormalities unidentifiable by NIPT were triploidies ( n = 7, 21%), balanced ( n = 8, 24%) and unbalanced rearrangements ( n = 10, 30%) and level III mosaicisms ( n = 8, 24%). For conditions not identifiable by NIPT, fetal sonographic appearance was likely to have led to invasive testing for 10 of 17 (59%) pathogenic abnormalities. If a policy was adopted recommending invasive testing for FTS risk >1:50 and/or ultrasound detected abnormality, the residual risk of an unidentified pathogenic chromosomal abnormality in those without a diagnosis would have been 0.33% (95% CI 0.01-0.65%). Conclusions A screening model with NIPT as a second-tier for high-risk pregnancies would be unlikely to have changed the outcome for the majority of pregnancies. Optimising the diagnosis of rare pathogenic abnormalities requires clear indicators for invasive testing over NIPT. [ABSTRACT FROM AUTHOR]

Since the early 1980s, prenatal screening using ultrasound and biochemical markers has been used to refine the risk of Down syndrome and other fetal anomalies prior to considering fetal karyotyping. The performance of prenatal screening is subject to ongoing monitoring in Western Australia. The collection of these data can also assist in the identification of any potential inequities of access to prenatal screening within the state-wide programme. Prenatal screening data (2005-2006) were collected from accredited ultrasound and pathology laboratories in Western Australia. Screening data were linked to diagnostic and pregnancy outcome data. Performance characteristics of screening and uptake by socio-demographic characteristics were analysed. Complete screening data were collected for 35,142 of the estimated 38,081 women screened during 2005 and 2006. There were 59,999 births related to this screening period. The lowest uptake of screening was among women who were Aboriginal (14.9%), living in remote areas (38.0%), under the age of 25 (40.2%), in the lowest quintile of the SEIFA index (41.6%) and with three or more children (48.4%). Logistic regression analysis showed all socio-demographic factors to be strongly associated with screening behaviour, with adjustment for ethnicity, socio-economic status, age, parity and area of residence. Our results have important implications for the delivery of prenatal screening services in Western Australia. While the screening programme meets international and national performance standards, the disparities in screening uptake suggest inequity in access to services, particularly for Aboriginal, remote and socio-economically disadvantaged women. [ABSTRACT FROM AUTHOR]

The article introduces a report by Caroline Crowther that is concerned with screening for group B streptococcus.

Antenatal screening for, and prompt management of, sexually transmitted infections (STI) can prevent adverse maternal, fetal and perinatal outcomes. This is particularly important in areas of high STI endemicity. To assess adherence with antenatal STI screening guidelines in a large remote region, and whether completeness of antenatal syphilis screening improved after the onset of a regional syphilis outbreak in April 2001. Data from the regional antenatal syphilis screening database from 1997 to 2002 were analysed to identify time trends in the completeness of antenatal syphilis screening. Adherence to antenatal screening guidelines was assessed by examining pathology request forms of women undergoing antenatal syphilis screening to determine whether screening for gonorrhoea, chlamydia, hepatitis B and HIV had also been carried out. Logistic regression was used to analyse associations between adherence to the guidelines and patient's age and race, and health service characteristics. Adherence to syphilis screening guidelines improved from 44.6% in 1997 to 68.9% in 2001 and 81.4% in 2002. After controlling for the time interval between the first antenatal syphilis test and date of delivery, being younger and Aboriginal, and delivering after the syphilis outbreak had been identified were positively associated with adherence to syphilis screening guidelines. Proportions of antenates screened for gonorrhoea/chlamydia, hepatitis B and HIV at booking and for gonorrhoea/chlamydia in the third trimester were 69%, 91%, 68% and 77%, respectively. Aboriginal women were more likely to have been screened for gonorrhoea and chlamydia. Women seen by a doctor were more likely to have undergone HIV screening than those who saw a nurse. Significant improvement in adherence to antenatal syphilis screening guidelines occurred after identification of a syphilis outbreak. This achievement is reason for optimism regarding the potential to achieve more complete antenatal screening of other STI. [ABSTRACT FROM AUTHOR]

Abstract Objective: To assess the level of knowledge about Down syndrome screening among a sample of health professionals providing antenatal care. Design: A structured questionnaire-based survey. Setting: Health professionals allied to a tertiary level maternity hospital in metropolitan Melbourne. Methods: A self-administered questionnaire was given or posted to 166 health care providers to assess their knowledge of prenatal Down syndrome screening. Results: A total of 140 completed surveys were returned (83% response rate), including 70 from general practitioners, 34 from midwives, 33 from obstetricians and three from geneticists. Of these, 130 confirmed that they regularly counsel women about prenatal screening for Down syndrome. Sixteen per cent of those indicated that they only offered testing to selected ‘high risk’ women rather than all women. Overall, there was a high level of awareness regarding the gestations at which the commonly used screening tests are offered but a poor appreciation of the relative performances of those tests. Seventy-eight (60%) of those counselling indicated that they discussed detection and screen positive rates specific for the age of the woman. However, less than 10% were able to provide those rates. Conclusion: Knowledge of Down syndrome screening was variable among those who regularly counsel women about these tests. The results of the present survey highlight the need for professional education about prenatal screening. [ABSTRACT FROM AUTHOR]

With the rapid uptake of noninvasive prenatal testing ( NIPT), certain technical and ethical limitations are becoming more widely recognised; however, there are still some salient issues that seem to be left by the wayside. As the consumer driven push for NIPT increases, healthcare providers need to ensure that they are providing testing appropriately and that patients understand the potential limitations and results as well as the benefits. [ABSTRACT FROM AUTHOR]

Objective: To assess the uptake of HIV screening in pregnant women attending a tertiary hospital antenatal clinic. Methods: An audit was undertaken in an antenatal clinic where HIV screening was routinely offered to all women following counselling. For the women offered HIV testing, note was taken whether the woman agreed to testing or refused, and if so, the reason for refusal. Results: Sixty eight percent of women who were offered testing opted to have the test performed. Thirty two percent of women decided against testing, with half of these reporting a recent (negative) HIV test result. Conclusions: Over 80% of pregnant women were willing to have HIV testing. Implications: With the introduction of recommendations that all pregnant women be given the opportunity for HIV screening, a high participation rate can be expected from women who are offered testing, with the potential for minimisation of vertical transmission by identification of HIV positive women. [ABSTRACT FROM AUTHOR]