Hi, ive been on the pill for almost 4 months, i just started my fifth pack.
I had sex with my boyfriend october 21 which was two days before finishing my 4th pack on the 23rd.
I finished the pack and after three days i got my period on the 26th of october, it lasted 5 days approximately. On sunday the 31st i started my fifth pack.
I was wondering if i could still be pregnant, because i had sex so close to having my period??
Thank you so much

You are most likely not pregnant, providing you have not forgotten any pills. That you have already had four packs, you should be okay. The pill is highly effective, if taken as prescribed.

There is a lot of good information online about birth control, how it works, and when it becomes effective. Here is one example:

How Long Does it Take for the Birth Control Pill to Work? | eHow.com