I have read on the internet that you can use cervical position to track your fertility. My period is due in two days and usually my cervix has dropped by now since I've been tracking it for the last few months. I know the chances of pregnancy in my case are very slim since I'm a perfect pill user an...

So I've been on yaz for 5 years now. My boyfriend and I have been having sex making sure to use a condom every time. I'm wondering how reliable this method is at preventing pregnancy? I'm very consistant with taking my pills. I'm also wondering if you can build a tolerance to your BC after taking it...