Retrograde Ejaculation Analysis

In certain medical conditions the semen may pass directly into the bladder (retrograde ejaculate), rather than being expelled from the tip of the penis (antegrade ejaculate). The sperm can be recovered from the urine by urination into a specimen cup, or catheterization directly after the male reaches climax. Before retrograde analysis of sperm can happen the patient is treated to neutralize (alkanilize) the pH of their urine. This is done by either ingesting bicarbonate tablets, or by a physician instilling media or buffer directly into the bladder prior to masturbation. Without neutralizing the pH of the urine, all or most sperm would die upon entering the bladder.


Patient Instructions: Alkalinizing your urine for Retrograde work up

Materials needed:


  • pH paper: purchased at an aquarium or pharmacy.
  • bicarbonate tablets: available over the counter and come as 650mg tablets.
  • time: you will need to test the pH of your urine a few days prior to the appointment to be sure it is alkalized.

To start, you will test the pH of your urine with pH paper. The goal is to get the pH of your urine between 7.5-8.5. To alkalinize your urine you will take sodium bicarbonate tablets. We recommend that you start with 2 tablets, four times a day. After 24 hours, test your urine pH. If it is still too low then take three tablets four times daily. You can take up to four tablets four times a day. If you are unable to get your urine pH in the proper range please contact the lab. If you have any heart problems please let us know prior to starting this regimen as there is an excessive amount of sodium in the bicarbonate tablets. Once you are able to get the pH right, try it a few times before you come in to give a specimen. This will ensure your sperm will be safe and result in an accurate analysis.


To dilute your urine within the half hour before collection drink three to four 8 ounce glasses of water.


Directions for collection for a Retrograde Analysis:


  1. Call the lab to schedule a retrograde semen analysis.
  2. Abstain from ejaculating for 2-5 days prior to the appointment.
  3. Take the appropriate number of bicarbonate tablets the morning of your appointment and check your pH. If your pH is incorrect call and cancel your appointment.
  4. Between fifteen minutes and half an hour before producing your sample, drink 3-4 glasses of water.
  5. Urinate to completely empty your bladder immediately before producing your sample.
  6. Masturbate and collect any ejaculate in one cup. Save this.
  7. As soon as possible after masturbating, urinate into a second cup.
  8. Bring both of the cups to the laboratory for processing.