Thank you for reaching out to us.

Since norethindrone acetate works to delay your period, you do not need to observe your regular vesatot while you are taking it.

Instead, you should observe a veset on the last onah (day or night) of the range in which the package instructions indicate that bleeding is likely to begin after you stop the medication. For example, if the instructions state that you are likely to bleed 3-7 days after you stop the pills, you would observe a veset on the seventh day.

Although only the final onah is a veset, we do recommend exercising caution with relations from the first day on which bleeding might be expected, based on the package insert. For example, if you are considering having relations, you could first wipe externally with toilet paper, not immediately after urination, to check if you are staining. Blood on the toilet paper would not make you niddah (learn more here). If you find staining, we recommend abstaining as a precaution until it is clearer whether the staining is increasing and turning into a period.

This is similar to the halacha with hormonal contraceptives (learn more here).

Please get back to us with any further questions.

This response was updated on 10 November, 2025.