How Long Can Ruptured Saline Implants Stay in my Body?

I agree with the answer below- tightening of the connective tissue pocket around your implant will progress with time.
While this is possible to improve at surgery, the chances of you achieving an excellent outcome and symmetry are higher if you have this managed sooner rather than later.
Having said that, there should be no risk to your health if you are unable to deal with this immediately.

It cannot cause harm.  It is in fact no different now than it was when it was full of saline.   The pocket may close and it may be difficult to retire your breast shape if you wait too long, but the implant shell itself won't harm you.

It's best to replace a ruptured saline implant within the first month after the rupture. If you wait longer, the overlying skin and the capsule around the implant will begin to shrink. It becomes more difficult to perform the surgery and to get good symmetry when the implant has been ruptured for a long time.

In my practice, I do not recommend leaving any ruptured or compromised implant device in a patient for any extended period of time.  I recommend and prefer replacing a ruptured implant immediately (or as early as possible) as the capsule, or layer of scar tissue that surrounds the implant, will begin to shrink down and tighten around the compromised (deflated) implant making replacement of the implant a more involved procedure.  If for personal reasons you are unable to take care of this deflation right away, there is no real risk to your personal health as the saline can be easily absorbed by the body.  But keep in mind that leaving this deflated implant for an extended period of time can potentially compromise the final cosmetic result when you are in fact able and ready to undergo an implant exchange.    

A ruptured saline implant will not cause injury or illness and does not need to be removed with haste.  It would typically be quite safe for you to have the ruptured implant in your body for some time until it is convenient to have it removed and replaced.  

It is advised to get deflated implants removed as soon as you notice the rupture because it makes replacement easier. However, if it's been a while and you haven't noticed any problems, it's fine to keep them until you do have a chance to have them removed or replaced. 

When patients have deflated saline implants the results can be very dramatic. These implants flatten rapidly and patients suddenly find themselves with significant breast asymmetry. This can create anxiety and because of this, patients are eager to have the problem corrected as soon as possible. For this reason, we don’t see a lot of women with deflated implants for prolonged periods of time.
Surgeons are also eager to correct the problem as soon as possible. They realize that with time, the implant pocket starts to shrink. This may be accompanied by creases and folds in the deflated implant, which can cause erosions through the skin.
With the passage of time, revisional surgery becomes more difficult with a greater potential for complications. When implants are replaced early, all that is necessary is a simple exchange of the old deflated implant for a new one. When the empty implant is left in place for a prolonged period, the implant pocket may need to be re-created because of shrinkage.
Although we recommend removal and replacement of a deflated implant at the earliest possible date, we realize this isn’t always possible.  In theory, empty saline implants can be left in a place indefinitely.  If this situation arises, it’s important to consult a board-certified plastic surgeon to discuss the pros and cons of leaving a deflated saline implant in place.

Replace Ruptured Saline Implants Promptly. I would recommend that you replace the ruptured saline implant within the near future. By waiting the pocket shrinks down and then has to be reopened. On the other hand if you replace them on a timely basis all your surgeon has to do is to simply replace it. This is a simple procedure and instead of waiting I would recommend seeing a local board certified plastic surgeon to take care of this. See the below link to find a well trained plastic surgeon in your area

In my experience this should be attended to in days not weeks. Waiting will cause shrinkage of the capsule and an asymmetry because the the newly operated breast will be harder or higher. If the implant rupture has been ignored for months, I believe that the capsule has to be removed to avoid the hardening.

A leaking or deflated saline implant is not an emergency but it should be attended semi urgently. Once the implant fluid is absorbed by your body, not only will you have an apparent "deflation", but your body will begin to tighten the capsule around the implant making future surgical corrections more difficult. If attended to within a week or two, the implant can simply be removed and another inserted. This can be performed under local anesthesia. However, if you wait too long, you might need removal of the implant with removal or release of the constricted capsule surrounding your implant. I suggest you call your Plastic Surgeon and he/she will assist you in exchanging your implant. But, do it quick!

Saline breast implants don't leak, they rupture and deflate pretty quickly. A partially or completely deflated saline implant can be left in place for a few weeks but the pocket will shrink slowly and scar tissue can set in making the replacement a little more difficult in some patients.It is not unreasonable or unsafe to wait a few weeks before replacement.