Should I do a post-vasectomy semen test?
Yes, almost all physicians who do vasectomies would recommend at least one semen analysis after a vasectomy. The guidelines from the both the American Urological Association and the Canadian Urological Association recommend doing a follow-up semen test to be sure, and Dr. Curington follows these recommendations also. It’s good to keep using contraception after the vasectomy for at least twelve weeks and then to do a semen test to confirm that you are in the clear.
When should I do a post-vasectomy semen test?
The best time to do a post-vasectomy semen test is 12 weeks after the vasectomy. By that time, just over 90% of men will have azoospermia (“no sperm”) in their semen. It takes surprisingly long to clear the sperm from the walls of the vas tubes and from the seminal vesicles. If you do your test earlier than 12 weeks, you will just have a higher chance of needing to repeat the testing.
What are the usual results of the post-vasectomy semen test?
There are three typical results – copious sperm, rare sperm, “no sperm seen.”
What does it mean to have “copious sperm” in the post-vasectomy semen test?
Sometimes a man will send in a sample very early after a vasectomy and there will still be many sperm seen by the lab. For example, a patient can send in a sample at six weeks and still have many sperm left hiding in the prostate and seminal vesicles. This just means the man needs to wait longer to flush out the residual sperm. Very rarely, a significant passage will form between the ends of the tubes and this channel will allow sperm to pass freely. This is rare, but can happen.
Usually, if you have a lab result of copious sperm in your sample, your physician will recommend that you continue using contraception, do a repeat test in a month, and decide on the best course of action from there.
Years ago, when a vasectomy involved simply snipping the tubes, around 5% of men would have significant sperm present in several samples after a vasectomy. With the modern method of vasectomy, though, the vas tubes are snipped, cauterized, and tied apart, so there is much less chance of a failure. With the modern method of vasectomy, only about 1 man per every 2,000 cases (0.05%) will need a repeat procedure.
What does it mean to have “rare sperm” in the post-vasectomy semen test?
After a modern, highly-effective vasectomy, around 10% of men will have “rare sperm” in the semen sample after 12 weeks. For the majority of men, this will simply clear itself up in a few weeks to a few months. The rare sperm in the sample are thought to be from a few “leftover” or residual sperm. These residual sperm calls can be retained in the seminal vesicles near the prostate or on the wall of the vas deferens. In other cases, as the healing cells form a scar over the ends of the vas tubes, the young scar can be soft and porous. The early scar can allow a few sperm cells to pass. Within a month or two after the first test, the scar usually solidifies and settles into its final state of not allowing even the rare sperm to pass. So, if you are one of the men who have rare sperm in your post-vasectomy semen test, the next step is usually to wait a month, continue using some form of contraception, keep flushing the tubes out with plenty of ejaculations, and repeat the sperm test. Your physician will chat with you about the next steps. With the modern method of vasectomy, only about 1 man per every 2,000 cases will need a repeat vasectomy.
If I have “no sperm seen” as my results after my vasectomy, should I do a second test?
If you have “no sperm seen” as your results after a vasectomy, you have a fantastic, highly-effective method of contraception. After clearance by a reputable lab, most men feel very satisfied with their results. After achieving “azoospermia,” or “no sperm” in the semen, the chance of causing a pregnancy is very very low – around 1 in 2,000 or even less. Still, nothing is perfect. If the chance of a reconnection worries you, you can do another test. Some men do a repeat test every few years. The test is easy and inexpensive. You can choose whether you want to do repeat test, and how often. It’s up to you.