The IMITAS study: IMplementation of fIrst Trimester Anomaly Scan

BACKGROUND There is increasing evidence that a significant proportion of structural fetal anomalies seen at mid-gestation can be detected in the first trimester. In 2016 the Health Council advised the Dutch government to initiate a nationwide study to gather more evidence on the added value of a first-trimester anomaly scan (FTS) in the current screening program and to explore all relevant implementation aspects. The ultimate goal is to determine if the advantages outweigh possible disadvantages of the introduction of a FTS. The pre-defined framework in which this study needs to be performed is: * FTS implementation study must start in 2021 * Equal options for all women; FTS cannot be introduced regionally (step wedge design) * All knowledge gaps, collected among the different stakeholders, represented in the grant call, need to be answered * Inclusion of an ethical analysis. The knowledge gaps comprise three main areas: 1) uptake and test performance; 2) women and partners' perspectives; 3) aspects of embedding FTS in current obstetric care. The IMITAS-study will address: OBJECTIVES * To gain insight in the consequences of FTS in a low-risk population (uptake, test performance, time till diagnosis, pregnancy outcomes including the number and gestational age of terminations). * To gain insight in the perspective on and experiences with the FTS of women and their partners. * To compare different scenarios in the whole chain of prenatal screening, including an analysis of health care professionals' perspectives, as well as a cost analysis. * To analyze all results with an ethical consideration. DESIGN AND METHODS A before-after design is proposed, as this is the best option to enable a proper comparison within the pre-defined framework. In the before period (1-9-20 – 1-3-21) data are collected prospectively, that are currently not available in the databases in use (mainly outcome of pregnancy and experienced burden of termination at mid-gestation). In the after period (1-3-21 onwards) data are collected to evaluate all FTS implementation aspects. I. Uptake and test performance All test characteristics of the FTS, including uptake will be retrieved from Peridos (national screening registry) and Astraia in the 8 centers for Prenatal Diagnosis. From referral after FTS, the time to definitive diagnosis will be determined, including number of subsequent scans, number of counselling sessions, type and number of follow-up tests. Clinical outcome of pregnancies with abnormalities will be recorded. Outcome of pregnancies with normal test-results will be retrieved with use of the Dutch birth registry. II. Women and partners' perspectives Two nationwide cross-sectional questionnaire studies will be done to study: 1) the experiences among women and their partners, offered FTS (at 3 defined times in gestation and after birth), and 2) the impact of abnormal test-results. Validated questionnaires will be used including measures on informed choice, decisional conflict and anxiety. Moreover, a semi-structured interview study will be done to explore and compare the (psychological) impact of termination of pregnancy among women after abnormal FTS (early gestation) versus SAS (late gestation). III. Aspects of implementation and embedding in obstetric care Healthcare professionals’ experiences with FTS and possible uncertainty with early diagnosis will be studied using exploratory interviews and questionnaires. To investigate embedding in obstetric care, we will compare 3 different scenarios for implementation, which will be theoretically analyzed based on the results of part I and II, from a health care perspective (medical outcomes), a patient + professional perspective (discrete choice experiment), as well as a societal perspective (budget impact analysis). IV. Ethical considerations The ethical analysis will build on the empirical results of part I-III. This will be done with the use of general and reproductive screening criteria. ANTICIPATED RESULTS The IMITAS study will result in a complete overview containing all aspects that the Minister of Health can use to decide on the best possible strategy for introduction of the FTS in the Netherlands, in terms of benefits for pregnant women in an ethically weighed approach. A complete summary will be provided on the uptake and test performance of the FTS, including a proper comparison with the current screening program, with a specific focus on the balance between the advantages and the possible negative aspects of the FTS. A weighing of all aspects will be performed with an ethical consideration, as women and partners' perspectives are extensively monitored during the introduction. We will also provide a road map for future implementation that will involve different scenarios (including a budget impact analysis) for the whole chain of care in the prenatal screening, including other tests as the dating scan, aneuploidy screening and midgestational anomaly scan.