Objective: This study aimed to evaluate the usefulness and safety of a new method for taking a placental biopsy. Methods: The procedures were performed using the traditional single needle technique (group 1) or the new method (group 2). In group 2, the piston was fixed in a simple metallic clip and the negative pressure was maintained in a continuous manner which was controlled with a three-way stopcock. Results: Multiple uterine insertion was necessary in 14 cases (32.6%) in group 1 and five (11.9%) in group 2 (p < 0.05). The amount of chorionic tissue obtained was significantly higher in group 2 (19.1 ± 15.0 mg vs 33.9 ± 17.4 mg p < 0.05). The abortion rates did not differ in either group. Conclusion: While using this technique, the operator is capable of performing the procedure without any assistance and of applying constant negative pressure only in the placenta. The advantageous outcomes are probably related to the size as well as the incessant fashion of the vacuum force.