How do I manage a patient who misses a dose of their combined hormonal contraceptive method?

If a patient misses a dose of their combined hormonal contraceptive (COC), management depends on how late the pill is taken and the day of the cycle on which it was missed.

• If the pill is taken less than 12 hours late: Advise the patient to take the missed pill immediately and continue taking the remaining pills at the usual time. Additional contraception is not required.
• If the pill is taken more than 12 hours late (or more than 24 hours late): Management depends on the cycle day:

• Days 1–7: Take the missed pill immediately and the next pill as usual (even if this means taking two pills in one day). Continue pill taking normally and use an additional contraceptive method (e.g., condoms) for 7 days. If unprotected sex occurred in the previous 7 days, consider the possibility of pregnancy.
• Days 8–17: Take the missed pill immediately and the next pill as usual. Continue normally. No extra contraception is needed if the previous 7 pills were taken correctly. If more than one pill is missed, use additional contraception until 7 consecutive active pills are taken. Consider pregnancy if no withdrawal bleed occurs at the end of the packet.
• Days 18–24: Either take the missed pill immediately and continue active pills, discard inactive pills, and start a new pack (withdrawal bleed may be absent), or discard the remainder of active pills and take up to 3 inactive pills before starting a new pack. Consider pregnancy if no withdrawal bleed occurs.
• Days 25–28 (inactive pills): Discard the missed pill and continue as usual. Additional contraception is not required.

If 2 or more pills are missed, especially if more than 7 consecutive active pills are missed, consider emergency contraception and advise the patient to restart the COC as a new user, using additional contraception until 7 consecutive pills are taken.

Advise that no more than 2 pills should be taken in one day. If vomiting or diarrhoea occurs within 3 hours of pill intake, the pill should be retaken and if illness persists for more than 24 hours, follow missed pill instructions and use additional contraception for 7 days.