How effective is the mini pill?
If taken correctly and as instructed to, i.e. every day at the same time each day, mini pills, or progestogen-only pills are more than 99% effective - with fewer than 1 in 300 users becoming pregnant within the first year of using the mini pill.
However the reality is that with typical use, 9 in every 100 users will become pregnant within the first year. Not using the mini pill correctly is a common reason for this.
There are some situations that can reduce how effective the mini pill is. This includes missed doses, vomiting, and interactions with certain medications.
What to do if you miss a dose
If you are taking a desogestrel-based pill (Cerelle and Cerazette are examples), a missed dose is where it has been over 36 hours since your last dose. If you are taking a norethisterone or levonorgestrel-based pill, a missed dose is where it has been 27 hours since your last dose.
You should take your missed dose as soon as possible. Regardless of how many pills have been missed, only one dose should be taken at this time.
You should take your next dose at the usual time, even if this means that more than one dose is taken in a single day.
And if you have longer than a 36 hour break - it will take three pills taken at the correct time to build up contraceptive effectiveness again. So take additional precautions for the next 48 hours from when you restarted the mini pill. This could mean using condoms or avoiding vaginal sexual intercourse during this time.
If you had unprotected sexual intercourse between the missed dose and 48 hours after restarting the mini pill, you may need to consider emergency contraception.
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