Nishmat's Women’s Health and HalachaIn memory of Chaya Mirel bat R' Avraham

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Uprooting long intervals

10 January, 2005


Thanks for your site. I looked through many of the posted articles/questions, but could not find the answer to this. Perhaps you can advise me.
I had a 55 day cycle, followed by a 32 day cycle. By the time the veset haflaga rolls around from the first period, I will have already finished the second, counted the seven days, and gone to the mikva.
Do I still need to observe that veset?


You do not need to observe the haflagah (interval) calculated from the first period. You calculate your interval only from the date of onset of your most recent period. Therefore, next month you will observe an interval of 32 days from the onset of your last period.

The question of whether a long interval can be uprooted by a shorter one is subject to halachic debate. Our position is as follows:

A veset she'eino kavua for interval is uprooted after one cycle only if you reach that date without becoming niddah. But if a long interval is followed by a shorter interval, as in your case, the long interval is not uprooted. Thus, you cannot actually uproot your 55-day interval until you reach day 55 without menstruating.

In practice, this means that any time you get your period before day 55, your interval clock restarts and there are no practical implications. However, if you ever reach day 55 without having menstruated first, you should observe it as an interval day.

In theory, the 55-day interval is never uprooted until you experience a longer interval. In practice, the custom is to note it at the top of your veset calendar and keep track of it for a year.

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