The longest that sperm can survive in fertile (egg white or watery) cervical fluid is five days. All pregnancies can be attributed to intercourse that takes place within the five days before ovulation and the day of ovulation.
Sperm, however, do not typically survive for five days, even in fertile cervical fluid. A life span of 2-3 days is much more typical for sperm, even in fertile cervical fluid- less without fertile cervical fluid.
To maximize your chances of conception, keep having intercourse until ovulation is confirmed by a clear and sustained thermal shift as intercourse closer to ovulation is much more likely to get you pregnant.