Hello i have a sex with my girlfriend on 1st october. she first period at 26 september and end at 2 october. after sex 8 hours my girlfriend took a morning after pill. can it cause pragnant ?

Sure: Having sex... that's how couples make babies, but can be prevented with pre-planning. The "morning after" pill can alter the menstrual bleeding for the cycle in which it was taken, and sometimes the next cycle too. One should be sure to check a home pregnancy test about 3 weeks after sex, because the pill works most of the time, but not all the time. Home urine pregnancy tests are very accurate.