Post-op Semen Analysis Interpretation

In a study by Majzoub and colleagues (Fertility Sterility April 2017), the authors reported that men with 5 million or more sperm (per milliliter) went on to achieve a pregnancy in 63% of cases.  Interestingly, even if men had more sperm (15 million or more), they did not have any higher chances of achieving a pregnancy (still 63%).  In contrast, those with less than 5 million sperm only achieved a pregnancy in 15% of cases. 

In a study by Majzoub and colleagues (Fertility Sterility April 2017), the authors showed that men who had a sperm motility of 10-40% at 6 weeks post-op went on to achieve a pregnancy in about 63% of cases.  Those who had more than 40% motility achieved pregnancies in 77% of cases, and those who had <10% motility achieved pregnancies in 21%. 

In a study by Majzoub and colleagues (Fertility Sterility April 2017), the authors showed that men who had less than 1% of normal forms in their semen analysis at 6 weeks post-op went on to achieve a pregnancy in the next 18 months in 15% of cases.  In contrast, those who have 1-4% of normal forms achieved pregnancies in 54% of cases, while those with more than 4% were successful in 79% of cases. 

Please note though that concentration and motility are probably more helpful in determining true potential for pregnancy compared to morphology.  In looking at published studies which include non-vasectomy populations, morphology is the least predictive of the major three semen analysis factors (concentration, motility, morphology).  Some studies report very low positive predictive values for morphology, such that some studies note that it is little better than flipping a coin as to whether or not it can help predict pregnancy (in non-vasectomy populations). 

Probably the best test to assess your chance for pregnancy post reversal is the total motile per ejaculate in a formal semen analysis.  This is calculated by multiplying your volume by your concentration and motility (motility should be in decimal form - i.e. 70% = 0.7).  In a study by Majzoub and colleagues (Fertility Sterility April 2017), the authors reported that men with less than 5 million total motile sperm achieved pregnancies in 28% of cases, whereas those who had 5-20 million had a 71% chance, and those with more than 20 million had a 69% chance.  

Other scientific publications which have reviewed the predictive ability of various semen parameters (in non vasectomy populations) have suggested that total motile counts are likely the best overall predictor of any semen test.  So, it is likely the case post-reversal as well. 

Sperm counts can fluctuate dramatically from one test to the next.  In one study of infertile couples, repeat samples obtained within the same man fluctuated by as much as 400-500% between tests.  Additionally, fluctuations are normal after vasectomy reversal surgery.  Because of this, comparing one test to another is often difficult.  Rather, it is more helpful to have several tests in a row, where a clear pattern can be seen. 

This is a good question, and the answer is, 'it depends on your goals.'  Some couples would not plan to do any post-op medications, IVF, or a redo vasectomy reversal if required.  In these cases, one could argue that there is little/no role for doing testing post-op at all.  In contrast, other couples will follow tests very closely and will take medications such as prednisone to try to improve counts from one test to the next.  In those cases, the most helpful thing would be to obtain formal sperm tests every month until at least 12-18 months post-op. 

In general, we recommend doing periodic testing at least for the first year.  After one year, testing every 3-6 months is reasonable.  During the first year, the ideal would be to obtain a formal semen analysis monthly, however, because of costs, most couples (essentially all) are unable to do this.  To help with costs, we allow patients the option of sending us tests as often as they would like to have concentrations obtained, and we will analyze them at no cost.  Although not as ideal as obtaining a full semen analysis every month, this is a reasonable alternative which still offers the ability to track results over time. 

Adjunctive semen tests have been used for decades and have included dozens of different types of tests, such as reactive oxygen species, antisperm antibodies, hamster oocyte penetration, DNA fragmentation, progressive motility, various methods of assessing morphology, and many, many more.  However, over the decades, no test has consistently been shown to be as good or better than sperm concentration and motility at predicting pregnancy. 

With that background in mind, we generally don't specifically recommend that patients obtain additional, specialized testing.  It is perfectly fine to get additional testing, but key decisions are made off of concentration, motility, total motile per ejaculate counts.  Similarly, concentration, motility, and total motile per ejaculate numbers are what are used to predict post-op pregnancy rates. 

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