Birth control methods have high rates of effectiveness
if they are used consistently. Follow your health professional's instructions
on what to do if you miss or skip your birth control pills. Some general
guidelines are listed here.
Combination (estrogen plus progestin) birth control pills
The greatest risk for pregnancy occurs if you start taking
combination (estrogen plus progestin) pills late or stop too early (that is,
you don't finish the month's worth of pills). If you use a 21-pill pack, you
take 3 weeks of hormone pills and go 1 week without pills. If your pills come
in packs of 28, the last 7 pills do not have hormones. If you miss a pill right
before or right after the week without hormones, you have a greater chance that
your body will release an egg (ovulate) and you will become pregnant.
If you do miss a pill, follow these instructions. If you had
unprotected sex during the time that you missed taking pills, call your health
professional right away and ask about
emergency contraception.1
- If you miss 1 pill, take it as
soon as you remember. Take your next pill at the regular time. If the
missed pill is at the beginning of the pill pack, discuss emergency
contraception with your health professional.
- If you miss 2 pills,
take 1 of the forgotten pills every 12 hours until you have caught up, then
continue taking the rest of the pill pack. Backup contraception is recommended
for 7 days. If missed pills are at the beginning of the pill pack, discuss
emergency contraception with your health professional.
- If you miss
more than 2 pills, skip the missed pills and complete the rest of the pill
pack. Backup contraception is recommended until your next menstrual cycle.
Taking the rest of the pill pack does not protect you from pregnancy but will
control your cycle. Discuss emergency contraception with your health
professional.
Vomiting and diarrhea can decrease the effectiveness of birth control
pills. It is recommended that another method of birth control be used for 7
days after you have had the
flu, even if you did not miss any pills. An
alternative is to insert the pills directly into your vagina so that absorption
through the stomach is not a concern. The pills must be inserted vaginally each
day just as you would take a pill orally each day to continue protection
against pregnancy.
Talk to your health professional if you are taking medications for
epilepsy (phenytoin and barbiturates) or tuberculosis (rifampin). These
medications may interfere with how well your birth control pills work.
Progestin-only pills
Progestin-only pills must be taken at the same
time each day. If a pill is taken more than 3 hours late, another method
of birth control should be used for the next 48 hours to prevent pregnancy. If
you forget to take a pill for even one day, you must use a second method of
birth control until your next period to prevent pregnancy.2 You can't take extra pills as with combination pills to make
up for a missed day. Progestin-only pills cannot be used vaginally if you are
vomiting because the dose is too low to be effective this way.