Prenatal diagnosis in the modern era

Key content It may be possible to define pregnancy complication risk in the first trimester by combining biochemical and biophysical markers with obstetric history. This could allow antenatal care to be personalised, with patient and complication-specific content. Molecular genetic testing, by both invasive and noninvasive means, can offer examination of the whole genome or exome. Noninvasive prenatal testing (NIPT) using cell-free fetal DNA in the maternal circulation can offer screening and diagnosis of aneuploidy and single gene defects. Ultrasound can be enhanced by magnetic resonance imaging to provide imaging that is not limited by fetal and maternal characteristics, and can be used to assist preoperative planning for fetal surgery. Learning objectives To understand how pregnancy care can evolve with NIPT and a more detailed first trimester assessment. To understand how NIPT is undertaken, its capabilities and current limitations. Ethical issues With increasingly detailed cytogenetic testing there is a need to provide families with sufficient pre- and post-test counselling, as well as consider the ramifications for them and the fetus.