How long does a sperm live?

  1. quasar987

    quasar987 4,770
    Science Advisor
    Homework Helper
    Gold Member

    Say, hypothetically, that I ejaculate on a hand, and 5 minutes later, said hand is introduced in a vagina. Are the sperms dead by that time?

    Thx
     
  2. jcsd
  3. Doubtful. It is more like little less than a few hours.
     
  4. Moonbear

    Moonbear 12,266
    Staff Emeritus
    Science Advisor
    Gold Member

    Okay, are you hypothetically retaining the sperm within the ejaculatory fluid, or are you hypothetically wiping most of the fluid away and concerned about the survival of the remaining sperm? Dessication (drying away the fluids) would substantially reduce the survival time. However, in the ejaculatory fluids, or once transferred into the female reproductive tract, sperm can live for several days (about 3 days on average).

    Hypothetically, one would be best off washing their hands in such a situation. :wink:
     
  5. DaveC426913

    DaveC426913 16,081
    Gold Member

    As Moonbear points out, the key factor is whether the ejaculatory fluids remain intact. The sperm will survive in it.

    Now, there are other practical factors in play, such as amount of transfer, degree of penetration and such, which will dramatically cut down the odds (of fertilization - which, I presume is the issue here), but the odds are definitely not zero.


    Hypothetically.
     
  6. quasar987

    quasar987 4,770
    Science Advisor
    Homework Helper
    Gold Member

    Ok, that helps a lot.

    Basically, since most of the fluid was wiped away and the rest had plenty of time to dry in 5 minutes, a great deal of sperms died. But, since they probably did not all die, and those that made it into the vagina can survive for 3 days, the probability of fertilization is non zero.

    And a side question: The way it works is that sperms are shot in the vagina embedded in their ejaculatory fluid. Once inside, however, they must exist this fluid and into some other vaginal fluid, in which they can survive just as well, that paves the way to the ovaries. Correct?
     
  7. DaveC426913

    DaveC426913 16,081
    Gold Member

    Basically, yes. The process is a little complex, environments acting partly to stymie the invaders and partly acting to aid them, but yes.
     
  8. I thought they died straight away! :biggrin:

    I guess it's all down to luck... :tongue:
     
  9. DaveC426913

    DaveC426913 16,081
    Gold Member

    I rather suspect quasar isn't smiling.
     
  10. If he's worried that much, he should logout and get down the chemist... :tongue:
     
  11. Moonbear

    Moonbear 12,266
    Staff Emeritus
    Science Advisor
    Gold Member

    Pretty much. The ejaculatory fluid actually needs to be diluted by the vaginal/uterine fluids for a process called capacitation to take effect (something in semen is an inhibitor of this process). Capacitation is a change in the head of the sperm that gives it the ability to penetrate through the membrane of an ovum and fertilize it (primarily an enzymatic process).
     
Know someone interested in this topic? Share a link to this question via email, Google+, Twitter, or Facebook

Have something to add?