[Foetal sampling techniques].

This article describes the current techniques of foetal sampling. All of them are actually ultrasound guided, and therefore generally very safe. Nevertheless, an elaborate learning process remains indispensable, in addition to a particular attention to the quality of the physician-patient dialogue. The choice of a technique depends on the indication and on the term of the pregnancy. The most frequently used technique is amniocentesis which presents a low risk of foetal loss, estimated between 0.2 and 0.5 percent. The interest of chorionic villus sampling is the possibility to obtain results at an earlier stage of pregnancy, with a lower risk taking when compared to early amniocentesis. We prefer the transabdominal chorionic villus sampling to the transvaginal. Foetal blood sampling is still required in some cases, but the risk of complications is higher--around 1 percent.