I was on the pill from the time I was 17, I always stayed on it, even though I was single for 3 years, and I never changed branfds, even when I lived overseas for a year.
I would very often skip the inactive sugar pills and continue straight on to the next cycle without having a period, (i hated having a period)
every so often, i'd do the right thing, and let myself have one.
When I was 23, my boyfriend and I got serious, and moved in together- he convinced me to have the inactive pills break, and have a period every month like I was supposed to, I agreed I was probably damaging my health or fertility, or both. So I gave it a try.
First month I took the inactive pills like you are suposed to. No period.
2nd moth, I faithfully went on to the inactives again -no period.
I was convinced I had rendered myself infertile from years of staying on the pill, or had messed my hormones around so much that maybe I had developed caner, or early menopause or something. I never missed a single pill ever, and I had not been on any meds at any time.
I went to the doctor. I was pregnant. I had an ultrasound, I was 8 weeks and a few days along.
My baby is now 2 and a half, i'm married to her father and i'm 35 weeks pregnant with her sister, (on purpose this time!!) so I guess it happened for the best, but at the time, it was the most impossible thing to believe- I was too shocked to even be glad that I wasn't dying of anything.
It can happen. I'd say most of the time pill failure is due to interferance from other med, or failure to absorb it because of an upset stomach, or forgetting to take it, but not for me, I was really one of those freak 1% failures.
I like to think of it as more of a miracle though- I wouldn't want to be without my little family for anything.