You have the highest risk of becoming pregnant during unprotected sex five days before you ovulate and on the day of ovulation.
Pre ejaculate fluid itself does not contain sperm.
If he had a recent ejaculation, sperm can remain in the urethra, which is the tube that urine and semen pass through. Once he urinates, sperm is flushed out.
Sperm can live in the woman's reproductive tract for about five days, so if you have sex five days before you ovulate, you could get pregnant.