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Urology/vasectomy slip


QUESTION: I am 38 i had a vasectomy about now 9 weeks ago and I was told that at 6 weeks or 20 ejacualtions I need to do the first of 2 semen tests. Well I forgot to do it at 6 weeks. But in meantime since 1 weeks after vasectomy I have had either thru sex or masturbation have ejaculated  about over 40 maybe 50 times and at 7weeks 5 days I was with my partner and there were no condoms and we elected the pull out of method and I ejaculated outside of her. At exactly 8 weeks to the day or just a few days after my little slip I got a semen analysis which was no sperm seen per my doctor. My question is what are my chances that this small slip may possibly get my gf pregnant? In previous relationships multiple times  I have used withdrawn method but never with her and that was before the vasectomy.


There is no way to know for sure or to calculate the exact risk percentage but it is likely to be very low.

---------- FOLLOW-UP ----------

QUESTION: What's more important ? The number of ejaculations or the time frame. I have read 15-20 is the number quoted on many sites. That's why I made me goal at 6 weeks to have 40 ejacukatjons by 6 weeks but missed my appointment until 2 weeks later and I continued until my first semen analysis and will continue until my second analysis. Also on the lab request it only asks for sperm and no sperm and not mention of mobility or non motility which it seems is another thing some urologists may ask for.

But I figured the risks are low. Just wanted another opinion. Thank you


It takes both the time and the number of ejaculations.  Time is needed for any remaining sperm to run out of energy.  The number of ejaculations obviously clears out the sperm already in the system.  Both are necessary for optimal results.  

We don't typically ask for viability, motility or morphology of sperm after a vasectomy because it is far more costly, more time consuming for the laboratory tech and unnecessary.  The critical parameter is whether or not there are any visible sperm left.  If there are, then regardless of the mobility or motility, there is a risk of a pregnancy.  We only ask for these other parameters when we are investigating infertility.


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Stephen W. Leslie, MD


Questions concerning erectile dysfunction, kidney stones and prostate disorders including prostate cancer. I have a special interest in kidney stone disease prevention.


Full time practicing urologist with 30 years experience. Associate Professor of Surgery and Chief of Urology at Creighton University Medical Center. Editor in Chief of eMedicine Urology internet textbook. Author of only NIH approved book written for patients by a urologist on the subject of kidney stones "The Kidney Stones Handbook". Inventor of the "Parachute" and "Escape" kidney stone baskets and the "Calculus" stone prevention analysis computer program.

American Urological Association, Ohio State Medical Association, Sexual Medicine Society

Men's Health, Journal of Urology, Urology, Healthwatch Magazine, Emergency Medicine Monthly, eMedicine, "The Kidney Stones Handbook", and numerous articles in various newspapers. He is also the editor of the Urology Board Review by McGraw-Hill used by urologists to study for their Board Certification Examinations.

Graduate of New York Medical College with residencies completed at Metropolitan Hospital New York, Albany Medical Center and University of Wisconsin-Madison.

Awards and Honors
Thirlby Award of the American Urological Association. Rated as one the country's Best Urologists by the Independent Consumer's Research Institute

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