If you are worried that robotic prostate surgery could make your penis look or measure shorter, this can happen, particularly during the early months of recovery. Changes in tissue position and fewer erections are thought to contribute.
For some men, penile length improves as healing and erectile function recover, although persistent changes can occur. Your specialist can also discuss sexual rehabilitation and what may be appropriate for you.
How Much Shorter Can the Penis Become?
There is no fixed amount you should expect. Studies have found that some men lose around 1–2 cm early after surgery.
Some penile length may recover over time as postoperative healing and erectile function improve. So, an early change does not necessarily mean your final result.
Evidence Note
A prospective study of 102 men measured stretched penile length before and repeatedly after radical prostatectomy. Average shortening was greatest 10 days after surgery, at approximately 19.9 mm, but penile length gradually recovered and was no longer significantly different from the preoperative measurement at 12 months.
Another prospective study of 105 men found an average reduction of about 1 cm at three months. The difference became smaller with longer follow-up and was no longer statistically significant at four to five years. These studies show that early shortening can occur, but the amount and degree of recovery vary between individuals.
Why Can Removing the Prostate Affect Penile Length?
It may seem surprising because your prostate is not part of your penis. However, removing the prostate changes the position of your urethra and nearby tissues.
Temporary anatomical repositioning after the bladder and urethra are reconnected, together with postoperative tissue and erectile changes, may affect how the penis looks or measures. This does not necessarily mean you have permanently lost penile tissue.
Does the Surgeon Remove Part of Your Penis?
No. Your surgeon does not remove part of your penis during robotic prostate surgery. The prostate and usually the seminal vesicles are removed, while your penis remains intact.
Instead, the position of your urethra and nearby tissues changes when the bladder and urethra are reconnected. As these tissues heal, your penis may look or measure slightly shorter.
Can Loss of Erections Contribute to Penile Shortening?
Yes. Losing erections after surgery may contribute to changes in penile size. When you have fewer erections, your erectile tissue gets less regular blood flow and oxygen.
This is why your doctor may recommend erectile rehabilitation during recovery. Treatments that support erections may help maintain penile blood flow and tissue health during recovery, although they cannot guarantee preservation of penile length.
Why Does Blood Flow Matter to Penile Tissue?
Good blood flow helps keep your penile tissue healthy and supports erectile function after surgery. Because you may have fewer natural erections during recovery, maintaining blood flow can become more important.
- Tissue Health: Regular blood flow helps deliver oxygen to your penile tissues and supports their overall health.
- Reduced Erections: Fewer erections after surgery can mean your penis receives less regular blood flow during recovery.
- Erectile Rehabilitation: Your doctor may recommend treatments that help encourage erections and support blood flow.
- Recovery Support: Improving blood flow may help support your sexual recovery, although it cannot guarantee that penile shortening will be prevented.
Your erectile recovery can take time after robotic prostate surgery. Your specialist can advise you on suitable rehabilitation options based on your healing and erectile function.
Does Nerve-Sparing Surgery Reduce the Risk of Shortening?
Nerve sparing may improve the chance of erectile recovery when it is oncologically appropriate, but it has not been shown to reliably prevent penile shortening. Penile length can still change even after nerve-sparing surgery.
However, your cancer treatment comes first. If cancer is close to the nerves, your surgeon may need to use a wider non-nerve-sparing dissection to maintain appropriate cancer clearance.
What If the Nerves Cannot Be Spared?
If your nerves cannot be spared, getting natural erections back can be more difficult. This may also mean less regular blood flow to your penis during recovery.
However, you still have treatment options. Your doctor may suggest a vacuum device or injections to help create erections while supporting your sexual recovery.
Is Penile Shortening Usually Permanent?
Not always. You may notice more shortening early after surgery, but your penile length can improve as your body heals and erections recover.
Some men may have lasting changes, so full recovery cannot be guaranteed. Your early postoperative measurement may not reflect your final result.
How Long Can Penile Length Continue to Change?
Your penile length can continue changing for months after surgery as your body heals and your erections recover. So, you may not see your final result in the first few weeks.
For some men, changes can continue for a year or longer. Your recovery can take time, especially if your erectile function is still improving.
Can a Vacuum Erection Device Help Maintain Penile Length?
A vacuum erection device may help preserve penile length in some patients during recovery while also supporting erectile rehabilitation. It works by drawing blood into your penis and creating an erection.
Your doctor may recommend using it as part of your sexual rehabilitation. However, it cannot guarantee that your previous penile length will be fully restored.
When Should You Start Using a Vacuum Device?
You should not start a vacuum device without advice from your surgical team. Your timing depends on how well you are healing.
The appropriate starting time varies according to your healing and your surgical team’s protocol. You should begin only when your clinical team confirms that it is safe, and the device should not cause pain or injury.
Can Viagra or Tadalafil Prevent Penile Shortening?
Medicines such as sildenafil (Viagra) or tadalafil can help erections after surgery. In one randomised trial after bilateral nerve-sparing prostatectomy, daily tadalafil was associated with about 4.1 mm greater preservation of stretched penile length than placebo after nine months.
However, this does not mean PDE5 inhibitors will prevent shortening for every man, and on-demand tadalafil did not show the same length benefit in that trial. Your doctor will recommend treatment based on your erectile recovery and individual circumstances.
What If Erectile Dysfunction Tablets Do Not Work?
If tablets such as Viagra or tadalafil do not work for you, you still have other options. Your doctor may recommend a vacuum device or penile injections to help you achieve erections.
If these treatments are not effective, a penile implant may be considered. Your specialist can discuss the most suitable next treatment option based on your nerve function, general health and preferences.
What Treatments May Support Sexual Recovery After Prostate Surgery?
Several treatments can support erectile recovery after prostate surgery, but they have different purposes and different levels of evidence for preserving penile length.
| Option | Main Role | What the Evidence Means |
| PDE5 inhibitor tablets | Treat erectile dysfunction, particularly when nerve function remains | Useful ED treatment, but not proven to prevent all penile shortening |
| Vacuum erection device | Mechanically draws blood into the penis and produces an erection | May support erectile rehabilitation and may help preserve penile length in some patients, although the most effective schedule remains uncertain. |
| Penile injections | Produce an erection by acting directly on penile tissues | Can work even when erectile nerve recovery is poor |
| Penile traction therapy | Applies controlled stretching to the penis | A small randomised trial reported improved or preserved stretched penile length, but evidence remains limited. |
| Penile prosthesis | Provides a mechanical erection when other ED treatments are unsuitable or ineffective | Established treatment for refractory erectile dysfunction rather than a routine treatment for shortening alone |
The right option for you depends on your erectile function, nerve recovery, healing and treatment goals. Your specialist can help you decide which approach is appropriate and when to start it.
Can Penile Traction Therapy Help?
Penile traction uses controlled stretching and may improve or preserve stretched penile length in selected patients after prostatectomy.
If you are concerned about shortening, ask your urologist if traction is right for you. Using it incorrectly can cause injury.
Research Insight
A randomised controlled trial enrolled 82 men after prostatectomy to assess a penile traction device. At six months, men using traction had a mean improvement or preservation in stretched penile length of approximately 1.6 cm compared with around 0.3 cm in the control group, and sexual-function measures also favoured the traction group.
However, only 55 participants had six-month data available for the main comparison, and the study was conducted at a single centre. The findings are promising but do not establish penile traction as a standard treatment for every patient after prostatectomy.
Can Robotic Surgery Cause Penile Curvature as Well as Shortening?
New penile curvature or Peyronie’s-like changes can occur in some men after prostate cancer treatment, alongside changes in penile length or erectile function.
If the curve is painful, getting worse or affecting sex, speak to your urologist. They can check the cause and suggest the right treatment for you.
Does Penile Shortening Affect Sexual Function?
Penile shortening may affect sex differently for you. You may find penetration harder, or feel less confident, especially if your erections are also weaker.
After surgery, changes to erections, orgasm and ejaculation can happen too. If these changes are affecting you, your doctor can support you with your sexual recovery.
Should You Measure Your Penis After Surgery?
You can measure if you are worried about a change, but you do not need to measure often. Small differences can happen depending on how and when you measure.
What matters most is how your erections, comfort and sex life are going. If you notice significant shortening, narrowing or a new curve, speak to your urologist.
UK Guidance Note
NICE recommends that people who develop erectile dysfunction after radical prostate cancer treatment have access to specialist erectile-dysfunction services. It recommends offering PDE5 inhibitors for loss of erectile function, with alternatives including vacuum devices, intraurethral treatment, penile injections or a penile prosthesis if tablets are ineffective or unsuitable.
Current European guidance also recommends discussing penile-size changes and Peyronie’s-like changes before prostate cancer treatment. It supports starting treatment for erectile dysfunction at the earliest appropriate opportunity after prostatectomy but notes that available data are insufficient to support any specific penile-rehabilitation regimen for every patient.
What Should You Ask About Penile Rehabilitation Before Surgery?
Before surgery, ask your surgeon how much nerve tissue they expect to preserve and when your erectile rehabilitation will start. You can also ask what treatments, such as tablets or vacuum therapy, will be available to you.
It is also worth asking about possible penile shortening, so you know what to expect during recovery.
Myth vs Fact
| Myth | Fact |
| The surgeon removes part of your penis during prostatectomy. | The surgeon does not remove penile tissue during routine radical prostatectomy. Changes in urethral position, healing and erectile function can make your penis look or measure shorter afterwards. |
| Everyone loses 1–2 cm permanently after surgery. | Studies have reported average early reductions of around 1–2 cm in some groups, but individual changes vary and some men experience substantial recovery over time. |
| Penile shortening is caused only by erectile dysfunction. | Reduced erections may contribute, but temporary anatomical repositioning and changes in penile tissues are also thought to play a role. |
| Using Viagra or tadalafil guarantees that penile shortening will be prevented. | PDE5 inhibitors are useful treatments for erectile dysfunction, but they cannot guarantee preservation of penile length. |
| A vacuum erection device has one proven schedule that everyone should follow. | Studies use different schedules, and current guidance does not support one specific penile-rehabilitation protocol for every patient. |
| Penile traction will restore everyone’s original length. | A small randomised trial found promising results, but evidence is limited and traction is not routinely needed for every patient. |
Key Takeaways
- Some men notice reduced penile length after radical prostatectomy, particularly during the early stages of recovery.
- Studies have reported average early reductions of around 1–2 cm in stretched penile length, but this is not a fixed amount and some men experience substantial recovery over time.
- Temporary anatomical repositioning after the bladder is reconnected to the urethra may contribute to early shortening, alongside changes in erectile function and penile tissues.
- PDE5 inhibitors and vacuum devices can help treat postoperative erectile dysfunction but cannot guarantee prevention or reversal of penile shortening.
- Current evidence does not support one specific penile-rehabilitation schedule for every patient after prostatectomy.
- Penile traction has promising early evidence but is not routine treatment for everyone and should be discussed with a specialist.
- New painful or progressive curvature, significant shortening or sexual difficulties should be discussed with your urology or erectile-dysfunction team.
Frequently Asked Questions
1. Can robotic prostate surgery cause your penis to become shorter?
Yes, you may notice that your penis looks or measures shorter after robotic prostate surgery. This can be linked to changes after surgery and reduced erections during your recovery. For many men, some improvement occurs over time.
2. How much shorter can your penis become after robotic prostate surgery?
There is no fixed amount of shortening you should expect. Some studies have found that men may lose around 1–2 cm early after surgery. Your penile length may improve as your erections recover.
3. Why can removing your prostate affect penile length?
Although your prostate is not part of your penis, removing it changes the position of your urethra and nearby tissues. As these tissues heal and your urinary tract is reconnected, your penis may look or measure slightly shorter.
4. Does your surgeon remove any part of your penis during robotic prostate surgery?
No. Your surgeon does not remove any part of your penis. Your prostate and usually your seminal vesicles are removed, while your penis remains intact. Changes in appearance or measurement are related to changes in the urethra and surrounding tissues.
5. Can losing erections after surgery contribute to penile shortening?
Yes. Having fewer spontaneous erections after surgery may reduce regular erectile blood flow and tissue oxygenation, which may contribute to postoperative penile changes. Erectile rehabilitation may help support blood flow and your sexual recovery while your natural erections return.
6. Is penile shortening after robotic prostate surgery permanent?
Not always. You may notice more shortening during the early stages of recovery, but your penile length can improve as your body heals and your erections recover. Some men may have lasting changes, so full recovery cannot be guaranteed.
7. Can a vacuum erection device help maintain your penile length?
A vacuum erection device can draw blood into your penis and create an erection, and it may help preserve penile length in some patients during recovery. Your doctor may recommend it as part of your sexual rehabilitation.
8. Can Viagra or tadalafil help prevent penile shortening?
Medicines such as Viagra or tadalafil can help you achieve erections by improving blood flow to your penis and may form part of your rehabilitation. However, they cannot guarantee that penile shortening will be prevented.
9. What can you do if erectile dysfunction tablets do not work after surgery?
If tablets such as Viagra or tadalafil do not work, you may have other options. Your doctor may recommend a vacuum erection device or penile injections. If these treatments are not effective, a penile implant may be considered.
10. How long can penile length continue to change after robotic prostate surgery?
Your penile length can continue to change for months as your body heals and your erections recover. For some men, changes can continue for a year or longer, so your early postoperative measurement may not reflect your final result.
Final Thoughts: Managing Penile Changes After Robotic Prostate Surgery
Penile shortening can occur after robotic prostate surgery, particularly during the early stages of recovery when erections may be reduced. For some men, penile length can improve over time as healing progresses and erectile function recovers, while treatments used for erectile rehabilitation, including vacuum therapy where appropriate, may help support sexual recovery.
If you are exploring robotic prostate surgery in London, our team at Prostate Clinic London would be happy to talk you through your treatment options and help you understand whether surgery may be suitable for you.
References:
- National Institute for Health and Care Excellence (NICE) (2019, updated 2021) Prostate cancer: diagnosis and management. Available at: https://www.nice.org.uk/guidance/ng131
- European Association of Urology (2026) EAU Guidelines on Sexual and Reproductive Health. Available at: https://uroweb.org/guidelines/sexual-and-reproductive-health
- Kadono, Y., Machioka, K., Nakashima, K., Iijima, M., Shigehara, K., Nohara, T., Narimoto, K., Izumi, K., Kitagawa, Y., Konaka, H., Gabata, T. and Mizokami, A. (2017) ‘Changes in penile length after radical prostatectomy: investigation of the underlying anatomical mechanism’, BJU International, 120(2), pp. 293–299. Available at: https://pubmed.ncbi.nlm.nih.gov/28181381/
- Vasconcelos, J.S., Figueiredo, R.T., Nascimento, F.L.B., Damião, R. and da Silva, E.A. (2012) ‘The natural history of penile length after radical prostatectomy: a long-term prospective study’, Urology, 80(6), pp. 1293–1296. Available at: https://pubmed.ncbi.nlm.nih.gov/23102441/
- Pirola, G.M., Naselli, A., Maggi, M., Gubbiotti, M., Rubilotta, E., Teoh, J.Y.C., Guarneri, A., Gauhar, V. and Castellani, D. (2024) ‘Vacuum erection device for erectile function rehabilitation after radical prostatectomy: which is the correct schedule? Results from a systematic, scoping review’, International Journal of Impotence Research, 36(3), pp. 194–200. Available at: https://pubmed.ncbi.nlm.nih.gov/37085734/
- Toussi, A., Ziegelmann, M., Yang, D., Manka, M., Frank, I., Boorjian, S.A., Tollefson, M., Köhler, T. and Trost, L. (2021) ‘Efficacy of a novel penile traction device in improving penile length and erectile function post prostatectomy: results from a single-center randomized, controlled trial’, The Journal of Urology, 206(2), pp. 416–426. Available at: https://pubmed.ncbi.nlm.nih.gov/34060339/
- Brock, G., Montorsi, F., Costa, P., Shah, N., Martinez-Jabaloyas, J.M., Hammerer, P., Ludovico, G.M., Lee, J.C., Henneges, C., Hamidi, K., Rossi, A., Mulhall, J. and Büttner, H. (2015) ‘Effect of tadalafil once daily on penile length loss and morning erections in patients after bilateral nerve-sparing radical prostatectomy: results from a randomized controlled trial’, Urology, 85(5), pp. 1090–1096. Available at: https://pubmed.ncbi.nlm.nih.gov/25813656/