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

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Onset of niddah and time zone changes

29 February, 2016


We live on the west coast of the US and traveled to the east coast on Sunday. I got my period that evening right after sunset. My question is as fellows: if we were still on the west coast that day, it would have been Sunday day since the west coast is 3 hours behind. Since I'll be back on the west coast by the time I go to the Mikvah, can I use west coast time and count Sunday as the first day, or do I need to count Monday as the first day?


The first day of your niddah period is determined by your actual location at the time the bleeding began. Since you were on the east coast at the time, and your bleeding began after sunset, Monday is considered day one. The fact that you will be travelling back to the west coast by the time you immerse does not change the circumstances in which your bleeding began.

Please feel free to get back to us with any further questions.

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