PDO thread lifts may provide effects that last anywhere from several months to more than a year. The length of time that the effects will last may vary based on the person, the kind of thread that was used, and the region that was treated. The stimulation of collagen production by the threads may persist for many months up to a year, although the threads themselves will be eliminated after 4-6 months. If you want a more exact estimate of how long the effects of the treatment will last, it is advisable to talk to a qualified medical professional.