Although all men undergoing a vasectomy are counseled that the procedure must be considered a permanent form of sterilization, a variety of factors (e.g., remarriage, loss of a child, etc.) may cause a couple to consider having a vasectomy reversed. The ultimate measure of success of such a reconstructive procedure is pregnancy and is dependent on several factors: the age and fertility of the female partner, the age and previous fertility of the male, the method of vasectomy, the surgeon’s experience, the technique of vasectomy reversal (the use of optical magnification/microscope), the quality of the fluid seen coming from the vas at the time of the operation, and most importantly, the length of time since the vasectomy was performed.
In a large study of 1,500 patients from multiple institutions, the success rate correlated most highly with the length of time since vasectomy. The shorter the interval from vasectomy to reversal, the higher the success rate. In men whose obstructed interval was less than 3 years, the likelihood of sperm being present in the semen after reversal was as high as 95% and pregnancy was observed in 75% of the female partners.
On the contrary, when the obstructed interval was greater than 15 years, only 70% of men had sperm in their semen following reversal, and the pregnancy rate was significantly lower at 30%. In most men, (i.e., those with obstructed intervals between 4-14 years), the likelihood of having sperm in the semen is about 80%, with a pregnancy rate of 45-60 percent. Upon interpreting this data, one should keep in mind that the age of the female partner plays an important role in the overall pregnancy rate. Men who are older, (i.e., those who have had long obstructed intervals), may have older partners.