Birth control effectiveness and the "perfect user"

[annabanana]

Hi there!

I have a question about birth control effectiveness - specifically the wording of what constitutes a perfect user. I take the combined birth control pill. I take the pill every day and have never missed one (never been 24+ hours late), however, since I'm not currently sexually active, I haven't been as careful as usual and there have been a couple of pills this year that have been taken late (I usually take them at 10 pm, and took them in the morning when I woke up instead (10-12 hours late). There was one this month that I took at 5 am, so 7 hours late. The wording of your article on BCP says that a perfect user takes the pill at the same time every day for a year (am I interpreting that right?).

My questions are, if I were to decide to become sexually active again this month or in the future, would I need to worry about a pregnancy risk (I would use a condom as well)? My other question is about the "in a year" wording - when you're on the pill does each new pill pack constitute a "clean slate" (i.e. if you take all the pills in the pack at the same time every day then you're a perfect user) or are you only a perfect user if you do that for a whole year?

Thanks!

[Mo]

Have you read this article about effectiveness and how it's calculated? I think that might help clear up how "perfect" vs. "typical" use are determined. Because all effectiveness numbers are calculated in studies over the course of one year, we can't really translate that into monthly statistics.
You have 12 hours to take a pill before it's considered "late" so as long as you're taking your pill within that time frame then its effectiveness isn't going to be compromised. Really, though, as long as you're taking your pill on time by that definition and using condoms as you mention, you're doing just about as much as you can to be protected. We have some statistics on the effectiveness of using a backup method of birth control here: The Buddy System: Effectiveness Rates for Backing Up Your Birth Control With a Second Method