by Pedro Miranda

Created on: June 05, 2009   Last Updated: June 07, 2009

All birth control pills are not created equal. When properly used, they are 99% effective in preventing unintended pregnancies; but what when you miss a pill? Or two?

For all practical purposes there are four types of birth control pills:

-Older (higher) dose pills, like OrthoNovum 1/50 or Ovral (Still used in certain cases)

-Low dose birth control pills like OrthoCyclen, Desogen etc

-Ultra low dose birth control pills like OrthoCyclen Low

-And finally, progestin only pills, like Micronor.

The older, higher dosage pills are more forgiving in terms of missing a pill; they have a large margin of error built into them. The lower the dosage of the pill, the less margin of error there is. When we reach the progestin only pill (used often when breastfeeding or when there is a reason to avoid estrogen) it is important, not only to take the pill every day, but also at the same time of the day to avoid an undesired ovulation, and its associated risk of pregnancy.

The following rules apply however to all of them:

If you remember during the same day, take the pill, and continue with your pack the next day, without any further worry. Even with the ultra low pills you should be safe. With the progestin only pill though, you should use a backup method of birth control (condom) for three weeks; this is due to the fact that progestin only pills often cause irregular menses or absence of menses; you may wish to take a pregnancy test at this time too.

If you remember the day after, take two pills right away, and continue with your pack the next day normally. If using the older pills or the low dose ones, again, you should be safe. If using the ultra low or progestin only pills, a backup method is recommended until you get your period, or a pregnancy test.

Finally, if you skip more than one pill, and you are on any birth control pill, except for the progestin only one, discard the rest of your pack, use an alternate method of birth control, wait for your menses to start and start a new pack. If you've had unprotected sex during these two days, it is recommended that you take the morning after pill, if you wish to be really safe.

If you've missed more than one progestin only pill, just take one pill and use a condom, or any alternate method for three weeks, and also get a pregnancy test in three weeks.

It is also important to remember that, if you are taking birth control pills, and need an antibiotic, especially of the tetracycline variety, you need to tell your provider so he or she can prescribe a high dose pill for a month. Women who are on anti-seizure medication need to be on high dose pills routinely, or use an alternate method.

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