Vasectomy reversal outcomes have improved over the years
Fortunately, medicine and surgery have come a long way. While there is unfortunately not a fix or cure for all ailments, the surgical field in male reproduction has seen improvements in vasectomy reversal rates over the decades with the refinement of techniques and decision-making.
How is success ‘defined’ for vasectomy reversals?
Over the years, there have been many different definitions of success. In short, there are technical success rates, and pregnancy or live birth success rates.
Technical success rates of vasectomy reversals
Technical success rates of vasectomy reversals have been defined several ways depending upon the group and publication.
Technical success of vasectomy reversal based upon any sperm in the semen
On one end of the spectrum, the lowest threshold to define a technical success is to count the presence of ‘any sperm’ that are detectable in the semen following a vasectomy reversal. While this likely reflects the connection has worked to some degree allowing the passage of rare sperm, it includes many outcomes that do not have much chance to result in a pregnancy.
Technical success of vasectomy reversal based upon more stringent criteria such as 2 million moving sperm
On the other end of the spectrum, more stringent criteria have been defined to be 2 million moving sperm. This typically reflects the lower end of acceptable numbers of ejaculated sperm for intrauterine insemination (IUI).
Intrauterine insemination
IUI is where sperm is washed then inserted into the uterus at a fertility centre while aiming to increase conception and pregnancy. The lowest threshold for IUI reported in the literature is 500,000 motile sperm, and a typical threshold is 5 million moving sperm. Importantly, while this threshold is much more rigorous than the presence of any sperm, and most men that reach this number end up with 10’s to 100’s of million of sperm, there will still be some patients that reach this count, but remain lower than desired for natural pregnancy.
How do we report our technical success rates of vasectomy reversals?
When reporting our outcomes for technical success, we report both definitions of ‘any sperm’ and ‘2 million moving sperm’. The former allows comparison to other reports in the literature which is important for comparative outcomes, and the latter is more relevant for discussion with couples.
Two types of vasectomy reversal connection types exists: Vasovasostomy (VV) and Vasoepididymostomy (VE)
Furthermore, when discussing vasectomy reversal success rates, it is also important to note that two different types of connections exist, and either may be required during a vasectomy reversal. The reason that this is important is because the technical success rates differ between the two techniques.
Let’s first explain this a little further…
What happens during a vasectomy?
The vas deferens is the tube that can be felt in the scrotum and transports sperm ultimately from the testicle to the ejaculate. During a vasectomy, a blockage is induced into the vas deferens typically through use of cautery, clip or suture.
What happens during a vasectomy reversal?
During a vasectomy reversal, we find this site where the vasectomy was performed and freshly cut the tube on either side. Most of the time, this is single blockage site where the vasectomy was performed. However, the testicle continues to make sperm and fluid even after the vasectomy. This fluid production can lead to an increased pressure within the storage unit tubules (i.e. epididymis); these tubules are thin and fragile, and this increased pressure can lead to a rupture of the tubules and subsequent scarring – now introducing a second site of blockage which is more common with increasing time since the vasectomy.
How does a vasectomy reversal surgeon determine if there are blockages beyond the vasectomy site?
To figure out if there is only one blockage at the vasectomy site, or multiple blockage sites, the vasectomy reversal surgeon is required to sample the fluid in the vas deferens tube and evaluate this under a microscope. If sperm or sperm parts are identified, then this suggests no additional blockages are present and a standard vasectomy reversal can be performed connecting the two ends of the vas deferens tubules together. However, if sperm parts are not identified, it suggests another blockage is present and the surgeon will then undergo additional fluid sampling in the storage unit tubules (i.e. epididymis) until sperm are identified. A specialized connection is then required where the vas deferens tubule is connected to the side of the small storage unit or epididymal tubule called a vasoepididymostomy or VE for short.
Increasing time since vasectomy results in higher chance of requiring VE type of connection
With increasing time since vasectomy, there is an increased chance of requiring a VE type of connection. In our study, we found that only 15% of men required the more complicated VE connection if time since vasectomy was between 0 and 5 years. However, this number increases to over 50% of men requiring the more complicated VE connection if their time since vasectomy was between 21 and 26 years.
Blue bars indicate bilateral vasovasostomy (VV) anastomosis; grey bars indicate bilateral vasoepididymostomy (VE); and green bars indicate mixed VV-VE anastomosis. (Image from Alhamam A, Liblik K., Witherspoon L., Dorner A., Flannigan R. CUAJ 2025)
What are Vasectomy Reversal Success Rates?
Now that we understand the different types of connections that are potentially required, let’s discuss the technical success rates of each of these scenarios.
Vasovasostomy (VV) success rates
Example of the technique that we use to connect the two ends of the vas deferens together, ie. Vasovasostomy (VV) using microdot sutures, precise stitch placement and a tension relieving approach. (Image from Alhamam A, Liblik K., Witherspoon L., Dorner A., Flannigan R. CUAJ 2025; Illustration by Dr. Kiera Liblik)
Vasoepididymostomy success rates
When a more specialized connection is required to overcome second blockages sites, the vas deferens is connected to the small epididymal tubule. In our reported series of cases, our technical success rates are 83% chance of seeing any sperm, and 77% chance of at least 2 million motile sperm.
Example of the technique that we use to connect the vas deferens tube to the small epididymal tube, ie. Vasoepididymostomy (VE) using microdot sutures and tension tension-relieving sutures. (Image from Alhamam A, Liblik K., Witherspoon L., Dorner A., Flannigan R. CUAJ 2025; Illustration by Dr. Kiera Liblik)
Mixed VV & VE success rates
In some circumstances, a VV type of connection may be performed on one side and a VE may be required on the other side. In these circumstances, our reported rates of technical success are 100% for any sperm and 88.8% chance of at least 2 million motile sperm.
Blue bars indicate rate of presence of any sperm, green bars represent rate of >2 million motile sperm following reversal procedure. VE: vasoepididymostomy; VV: vasovasostomy. (Image from Alhamam A, Liblik K., Witherspoon L., Dorner A., Flannigan R. CUAJ 2025)
Limitations of the results in our study
When reviewing medical or surgical studies, it is important to keep a critical eye for not only the outcomes but the limitations. While there is no study without limitations, it is important to note the limitations in our study and results. We included couples that underwent vasectomy reversal for the first time, and performed a sperm test within 6 months after surgery, and have at least 6 months follow-up of sperm testing. It is important to point this out, because there are a small subset of patients that did not have adequate follow-up, and therefore, it is unclear how this may impact the outcomes. Another important limitation of this study, and many other vasectomy reversal studies, is that a technically successful vasectomy reversal may not yield high enough sperm counts for a natural pregnancy in every case, so while achieving 2 million motile sperm is a more stringent criteria than most published reports, there are still some outcomes that meet this criteria but remain low for a natural pregnancy.
With all of this in mind, there remains positive chances of natural conception and pregnancy after vasectomy reversals. Let’s review some of the medical literature on this.
What are the chances of getting pregnant after a vasectomy reversal?
Getting pregnant and having a child is of course the ultimate goal of going through a vasectomy reversal procedure. However, collecting pregnancy information can be challenging, and therefore is a limitation to many studies. It is also important to note that there are a number of variables that can impact the chance of success beyond the vasectomy reversal itself. An important variable in this equation is female reproductive health. Factors that contribute to this may include the woman’s age, regularity of their menstrual cycle, and previous success in becoming pregnant. Female fertility testing is generally recommended and can be helpful in identifying any variables that could impact the success of natural pregnancy.
Pregnancy rates for couples undergoing vasectomy reversal have been shown to vary by the woman’s age
- Women under 30 years of age were reported to have pregnancy rates between 52% and 67% in one study.
- Women 30 to 34 years of age were reported to have pregnancy rates between 57% and 78% across two studies.
- Women 35 to 39 years of age were reported to have pregnancy rates between 54% and 78% across two studies.
- Women over 40 years of age were reported to have pregnancy rates of 14% to 42% across two studies.
Conclusion to vasectomy reversal success rates
Can you reverse a vasectomy? Yes, contemporary technical success rates for vasectomy reversal by a trained expert capable of performing both VV’s and VE’s are fairly high. Overall, our experience combining VV, VE and mixed VV & VE types of connections results in 97.7% chance of any sperm, but more importantly a 93.1% chance of greater than 2 million moving sperm. Pregnancy rates are ultimately more important than technical success rates, and can vary by a number of factors, perhaps the most important being female reproductive age.