Assessment of Women's Insight and Understanding of Non-invasive Prenatal Testing (NIPT) During Their First Trimester Ultrasound

Down's syndrome is the leading cause for mental retardation in France. Screening for this chromosomal abnormality is systematically proposed during pregnancy.

Until April 2017, prenatal screening for Down's syndrome was based on a combined screening test which included fetal ultrasound markers and maternal serum hormone levels prescribed after the first trimester ultrasound. Depending on this screening result, women that presented a higher risk of ill fetuses could benefit from invasive procedures (amniocentesis or trophoblastic biopsy) in order to have a karyotype and make certain diagnosis. The latter procedure involved risks of complications such as miscarriages, infections and water break.

A new screening procedure is available since 2017. It relies on detecting an extra 21 chromosome in cell-free DNA by a simple maternal blood test, called noninvasive prenatal screening (NIPT). This screening test is highly efficient with a detection of 99 % of fetuses affected by Down's syndrome and therefore enables practitioners to avoid 95% of invasive samples. NIPT implies to proceed to a diagnosis test as well (amniocentesis and trophoblastic biopsy) to obtain karyotype and confirm diagnosis.

Few studies show a concerning level of Down's syndrome screening general strategy. There is a clear lack of understanding of the information provided by the health professional during the first trimester ultrasound. Women report feeling uninformed and confused about French screening strategy. Nevertheless, high quality insight is essential to ensure validity of women's consent to perform Down's syndrome screening and quality of provided health care.

Since introduction of NIPT, no study has been carried out to assess women's prior knowledge to NIPT for Down's syndrome. Main objective of the study is therefore to evaluate women's information and understanding of Down's syndrome screening using NIPT. Secondary objectives stand in collecting modalities of the provided information by the doctor performing the first ultrasound and assess patient's satisfaction regarding this information.

Understanding of this new screening strategy by pregnant women is a key issue in decision making. This observational study is intended for all pregnant patients from 11 to 17 + 6 WA (weeks of amenorrhea) expecting a single baby, consulting in the obstetrics and gynecology department of the University Hospital of Reims for their 1st trimester ultrasound. Participation to the study will not change patient's medical care. The doctor who carries out the ultrasound will not be aware of the patient's participation in the study. Concordant results with literature using the experience of what was done for Down's syndrome screening prior to NIPT are expected. Communication on this matter to the lay public is scarce. Level of knowledge regarding NIPT before the consultation is expected to be insufficient. The absolute necessity of upstream information (brochure provided by secretaries, information disclosed throughout the three month pregnancy consultation, booklet delivered with initial documents ....) to enhance patient's comprehension and satisfaction will be highlighted.