Since this is not my area of expertise, I searched Google under the key words "life span of sperm after ejaculation" to get these possible sources:
http://www.google.com/search?client=safari&rls=en&q=life+span+of+sperm+after+ejaculation&ie=UTF-8&oe=UTF-8
In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.
You can add "in female reproductive tract" to your key words.
After ejaculation, the sperm can live for about ____ in the female reproductive tract
2 answers
48 hours