ABSTRACT
The legal definition of prenatal diagnosis (PD) involves “in utero detection of a condition that is particularly serious in an embryo or foetus”. The term PD is used to refer to any technique enabling this detection. Pre-implantation genetic diagnosis (PIGD or PGD) is undoubtedly the main innovation in prenatal diagnosis. It was initiated at the start of the 1990s in the UK, and the technique developed fast in France after authorisation in the law of 29 July, 1994. The 1980s saw the development of molecular biology techniques and the cloning of numerous genes responsible for relatively frequent genetic diseases, which have considerably improved reliability and the scope for early diagnosis, enabling the detection of healthy carriers in families. Specialised multi-disciplinary teams can diagnose very rare conditions, using a combination of ultrasound scans and genetic explorations. Molecular biology increasingly provides firm diagnosis, which is only really possible from ultrasound scans for the most obvious malformations.
