What Happens to Sperm After a Vasectomy?

Learn what happens to sperm after a vasectomy

Vasectomy is one of the most common, effective and convenient methods for birth control around the world. While most patients know that a vasectomy causes sterility by blocking the flow of sperm, what surprises many of my patients is that the procedure doesn’t stop you from producing sperm. This means you’ll continue to make sperm after your vasectomy— it just doesn’t leave your body.

The ins and outs of sperm production

Every day, on average, you make about 100 million sperm. It takes about three months for the sperm to mature once it’s made in your testicles. During that time, the sperm travels through your testicles until it reaches the epididymis, a way station between the testicle and the sperm tubes. These tubes (called the vas deferens) transport the sperm to the penis for ejaculation.

After a vasectomy, your vas deferens are blocked, but your testicles keep making millions of sperm each day.

So, what happens to your sperm after a vasectomy?

The sperm’s journey after vasectomy

After your vasectomy, as your sperm travels past the epididymis, it gets trapped in the blocked vas deferens. Most commonly, sperm is broken down into its basic building blocks and your body simply reabsorbs it. Even men who haven’t had a vasectomy reabsorb sperm— studies suggest that up to half of all sperm produced in the testicles is reabsorbed before ever reaching the vas deferens.

This is really efficient, since sperm is made up of proteins and sugars that can fuel other important body functions. Sperm reabsorption is completely natural; it won’t cause any problems for you and is not associated with any long term health conditions.

Sperm can also leak out of the cut edges of the vas deferens before being reabsorbed. Surprisingly, this can be a good thing because it decreases the back pressure in the testicles from the buildup of sperm waiting to be reabsorbed. Occasionally, this “leakage” can cause a mild reaction called a sperm granuloma.

What should you expect after vasectomy?

You won’t be aware of your body reabsorbing sperm. Some men may notice a sperm granuloma as a small lump at the top of the scrotum. It’s usually nothing to worry about— the lump often stays the same size or even goes away without causing any bothersome symptoms.

Occasionally, a man may notice some discomfort from the sperm granuloma. This tends to happen when it develops quickly (within a few weeks after vasectomy) or if it continues to grow without ever getting reabsorbed. In these cases, over the counter medicines can be quite helpful to manage any discomfort. Very rarely, a man may choose to get  the sperm granuloma removed, which is accomplished as a simple outpatient procedure.

Semen Analysis After Vasectomy

Because semen is still produced after a vasectomy, it is important to undergo a semen analysis before having unprotected sex. Most physicians use an arbitrarily determined time period or an arbitrary number of ejaculations before obtaining a semen analysis. In a survey of 1,800 physicians performing vasectomy in the United States in 1995, Haws and associates found that post-vasectomy semen analysis was obtained at six weeks or less by 59% of the physicians, at seven to nine weeks by 29%, and at nine weeks or more by 12%.*

If you’d like to learn even more about vasectomies, and if it’s right for you, contact Dr. Harry Fisch for a consultation.

Request a Consultation with Dr. Fisch