Is the Halacha different regarding Onos that are within a couple of months post birth?
Must they all be kept?
Is the difference only regarding Veses Kavua.
How does it work?
Answer:
After a birth one must keep the Onos (Hachodesh, Beinoni, Hafloga) only after she started having her period again (which usually will not happening for a couple of months after a birth).
Those Onos are to be kept as an “unfixed cycle”.
One cannot set up a fixed cycle during 24 months after a birth, even if 3 periods happen at the same date and Onah.
Source:
Y”D 189 33.
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