6 doctors weighed in:

How come only 28 pills come in birth control?

6 doctors weighed in
Dr. James Ferguson
Pediatrics
5 doctors agree

In brief: To Mimic Nature

The predominant pattern of natural menses occurs on a 28 day cycle.
(although some cycle on shorter or longer intervals) the bcp with either 21 active/pack with 7 days off or 21active +7 dummy pills in a 28 day pack for daily use is an industry standard. The 7 days off allows menstral flow, some give continuous active pills for 3-4 mo or more & decrease # of menses they have /yr.

In brief: To Mimic Nature

The predominant pattern of natural menses occurs on a 28 day cycle.
(although some cycle on shorter or longer intervals) the bcp with either 21 active/pack with 7 days off or 21active +7 dummy pills in a 28 day pack for daily use is an industry standard. The 7 days off allows menstral flow, some give continuous active pills for 3-4 mo or more & decrease # of menses they have /yr.
Dr. James Ferguson
Dr. James Ferguson
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