if you are absolutely sure your boyfriend had a vasectomy and does not have any viable sperm anymore. and he is the only one you are having unprotected sex with then the chance of pregnancy would seem to be zero. there are dozens of different reasons why a woman would miss her period other than pregnancy so please see your gynecologist so you can be properly examined.
what could cause a woman to miss a period. i have a bf that is fixed and we have been sleeping together for 7 months with out protection and this month i haven't had a period yet i was wondering what could be the cause i took a test this last friday and it was negative but i mite have tested to early