Your doctor can give the best advice. In general, fistula closures can take time. In some cases, I have urged my patients to wait for 6 months, or more, if in my judgment the fistula would close. If the fistula output has fallen the likelihood is high that it will close. It is usually not advisable to become impatient and try to close the fistula by another surgery. However, as I said earlier, you should follow your doctors advice. He can tell whether or not this specific fistula is likely to close.