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

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Extending cycle, breakthrough bleeding, and onot

6 March, 2018


Recently I started birth control pills and I am extending my cycle. So far, I have been taking the active pills until I start bleeding and then I switch to the placebo. Each month my cycle gets longer (I first bled after 30 days then 33 then 37…). The active pills can be taken for up to three months without a break.

My question is do I need to do the monthly/average onah if I know my period won't be till much later? And when would I keep onot? My last cycle was around 44 days and next one will, if I keep following this pattern, be longer.


There is halachic debate regarding veset observance when a woman consistently becomes niddah after the onah beinonit has passed.  We follow the ruling that once a woman has three longer cycles, she no longer is required to observe the day of the month or onah beinonit, but only observes the interval.  (Should she later experience a shorter cycle again, she would return to observing all of the onot.)  

If we understand you correctly, you at this point need only observe the interval.  If and when you no longer become niddah while taking these active pills, you may be able to switch to observing a veset based on the interval between cessation of active pills and becoming niddah.  Please do note that it is very common for women to experience breakthrough bleeding on extended cycle pills, even after they have been using them for some time. Please be in touch if and when other questions arise.

You may also find it helpful to review the laws of staining, as by reading our articles "Stains" and "Toilet Paper".


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