[Choriocentesis: comparison of the effectiveness of a new choriocentesis needle and a transcervical biopsy forceps]

71 samples taken by the transabdominal route were compared with 71 samples taken by forceps through the cervix. A fine (1 mm) transabdominal choriocentesis needle with a thin wall (0.1 mm), a short bevel, and a lateral hole was made to bring together simplicity, effectiveness and safety; success was obtained in 95% of the cases (39/41) of our last 41 samples on the first attempt. For comparison with the forceps, the success rate on the first attempt was only 66% (26/41), but it rose to 97.5% if the patient could take 3 attempts at most. The forceps made it possible to collect a mean quantity large enough (19.9 mg) but it was quite variable (16.7 mg being the range) of complete villi, whereas the choriocentesis needle only gathered a smaller volume (12.7 mg) but more reliable (the range being 3.7 mg). The villi were fragmented, however. To work out the study of the DNA and the karyotype, there is a choice between the forceps and the needle. This choice depends principally on the damage the two techniques can do. This has not been worked out yet in our study except indirectly.