Other Vasectomy–Induced Anti fertility FactorsThe important immune factors that trigger the autoimmune process are called leukocytes. Among their other harmful effects is the production of particles called oxygen–free radicals (also called reactive oxygen metabolites), which are particularly injurious to sperm. Vasectomy may also change other factors that affect fertility.
FailureAfter a vasectomy, there is still a 1.5% chance of pregnancy usually due to either live residual sperm or operative failure. Some reasons for failure of a vasectomy include incomplete sealing of the vasectomy differentia and the development of openings in the tubes that allow sperm to pass through.
Residual Live Sperm. After the operation there are always some active sperm left in the semen for several months, so it is essential that the patient and his partner continue to use another method of birth control until his sperm count is zero. Fifteen to 20 ejaculations are required to clear the viable sperm from the reproductive system, usually it takes a few months before sterility is complete.
A semen analysis is done about six to twelve weeks after the surgery to ensure that no live sperm remain in the semen. The semen is usually collected at home in a small jar and delivered to the doctor’s office where it is examined under a microscope. A second semen analysis is usually performed again about four months after the vasectomy. The patient is considered sterile only when there is no live sperm in his semen. The presence of non-motile sperm presents no problem.
The primary reason for vasectomy failure occurs when the cut ends of the vas deferens reconnect through a process known as spontaneous recanalization. This is very rare but may occur if a sperm granuloma and its resultant interconnecting channels form a new route for sperm to move from one cut end of the vas deferens to the other. Recanalisation has been known to occur as soon as a man has achieved a zero sperm count and as late as 17 months after vasectomy, but the overall risk for recanalization is only about .025% or one in 4,000 vasectomies. This natural vasectomy reversal can occur regardless of the type of vasectomy surgical procedure. Men should have a follow-up examination a year after the procedure to be sure that there are no residual or new sperm.
Future ChangesThose considering vasectomy should consider whether recent changes or stresses (an illness, temporary financial crisis, death in the family, or birth of a child) rather than rational, long–term consideration, are influencing a decision about permanent contraception. Vasectomy should not be thought of as a way to cope with short–term problems. Experts recommend that couples wait for a while if they face such situations or that they seek marriage counseling or psychotherapy to be sure that they are not making a decision they will regret later.
Before deciding on a vasectomy, the patient and his partner should be clear about their reasons for going through with the procedure. The couple should consider all scenarios for possible future life changes. If the man changes his mind after a vasectomy, he will have to undergo a major operation to reverse the procedure with no guarantee of restoring his fertility. The couple needs to consider how they would feel if their current relationship ended, either by divorce or the wife’s death.
In such cases, the man might find a new partner who wanted a child by him. What would happen if one or more children died? If financial stress is triggering the decision for a vasectomy, would improved affluence make a difference in determining the desire for children? Age is also a factor, for many young men who still have many major life changes ahead of them, vasectomy is probably not a wise choice.