Sex without any sort of protection - is never really safe! But to get the more "fertile" dates - you can use a Ovulation Calculator to measure the girls dates - those must be avoided - obviously you must avoid sex those days but just a reminder - this is not real guarantee that nothing at all will happen - just keep in mind, and to assure yourself - do a home pregnancy test. https://lovematters.in/en/our-bodies/ovulation-calendar-how-to-calculate-ovulation https://lovematters.in/hi/pregnancy/home-pregnancy-tests-dos-and-donts If you would like to join in on a further discussion on this topic, join our discussion board, "Just Ask” https://lovematters.in/en/forum