Peak Plus 4 Rule: One of the four rules of using FAM as birth control: you are considered infertile the evening (after 6 PM) of the 4th day after your Peak Day.
Peak Plus 4 Rule
Peak Plus 4 Rule: One of the four rules of using FAM as birth control: you are considered infertile the evening (after 6 PM) of the 4th day after your Peak Day.