Onot on Pill
9 March, 2005
Question:I am getting married in 6 weeks and I am already on the pill. I will be staying on it for a few months after the wedding, after rabbinic consultation.
I learned that when I am on the pill I don't have to count out and make "x"s on the three times the following month that I will expect my period. If that is the case, how do I know when I am in an "onah"?
Answer:The halachic status of hormonally controlled uterine bleeding, such as that which occurs when taking birth control pills, is a matter of debate among current authorities. Our approach is to initially ignore the birth control pills; however, if a woman establishes a pattern of three months of bleeding at a consistent interval after cessation of the pill, then she establishes a veset based on the interval from the cessation rather than the interval from the first day of bleeding.
In other words, the first three months on the pill would proceed with all the 'x'-es and the usual onot perishah. Once you have three months during which you do not bleed until after cessation of the pill, then the usual onot can be ignored. lf you establish an exact interval from when you stop the active pills until your period begins, that will become the onah you observe. If your period consistently comes within a limited range of onot from cessation of the pill, you will observe the entire range (up to three days) as an extended onat perishah.
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